text:
Talk:Compressor

Heat of compressed gas
The heat of a compressed gas does not come from the inefficiany of the machine compressing the gas. I am not sure why you insist on this error but I am not going to get into an edit war with you Mark.

A great and well respected company to get a compressor from is Ingersoll Rand. —Preceding unsigned comment added by 66.184.105.10 (talk) 20:26, 13 August 2010 (UTC) —Preceding unsigned comment added by Qaz (talk • contribs) 4 March 2004 (UTC)

Relative efficiencies
Can anyone provide any figures for the relative efficiency of the various designs of compressor? This is information I for one would find extremely useful.--81.179.91.108 23:55, 16 June 2006 (UTC)

 * I second the request of the above person. It would seem to me that a piston design would produce much lower efficiencies than a turbine design, but just how much better or worse?  I've dug into my thermo books, and can't seem to find anything on excpected mechanical efficiencies. ~ZirbMonkey - 27 June, 2006 read it by Badr AL-Sowayan

 * I would suggest that you read the Compressor Handbook, Editor: Paul Hanlon, published by McGraw Hill, January 2001, ISBN 0070260052. - mbeychok 07:49, 28 January 2007 (UTC)

 * I third the request, please. Hanlon's book isn't in any library I can find within 50 miles.Egmonster 05:05, 7 July 2007 (UTC)

 * It is very difficult to provide the "relative efficiences" requested above. First of all, there many differnt types of efficiency in use, for example: adiabatic efficiency, isentropic efficiency, polytropic efficiency, isothermal efficiency, volumetric efficiency, mechanical efficiency and overall efficiency.

 * Then there are certain parameters that affect the efficiencies, for example, the specific compression ratio and the percentage of load at which the compressor is operated.

 * As a generalization encompassing all the many types of compressors and all of the parameters that affect the efficiency, the range of adiabatic efficiencies is from 45% to 95%. Sorry, but I just cannot do any better than that. Perhaps someone else may have a better answer. - mbeychok 21:08, 7 July 2007 (UTC)

 * In the gas turbine business, efficiencies are usually quoted at the design point (often peak efficiency) and as polytropic efficiency which normalises for compression ratio. Decision on which type of compressor to use usually depends on flow rate and pressure ratio required.  However, axial compressors are slightly more efficient (up to low 90s) than centrifugal (high 80s) for flows greater than a certain size.  Of course, any benefit in efficiency comes at a cost.AlekH (talk) 23:30, 15 February 2008 (UTC)

Hydrogen compressor
The section, hydrogen compressor is missing. Mion 16:47, 31 July 2006 (UTC)

Air quality test
I need help. Carrying out an Air Quality Test of air compressed into an SCBA cylinder. The water value reads 180mg/m3. The cylinder is 9kg in size. The Standard required in the vessel where I work (FPSO is 30mg/m3. How is this possible for God's sake! Give me a clue. The test time is 10 Minutes using Drager kit. The instruction in the water tube is of October 2005. Is there a way of converting mg/m3 to ppm? Pls let me know. My email address is: mandupakpan@yahoo.com —Preceding unsigned comment added by 80.94.111.145 (talk • contribs) 9 January, 2007 (UTC)

 * Read this Wikipedia article: click here ==> Useful conversions and formulas for air dispersion modeling. It has exactly what you are looking for. - mbeychok 18:25, 19 January 2007 (UTC)

Reason for changing photograph
I replaced the original photo with a better one of a single-stage centrifugal compressor because I thought the original photo was a rather scruffy looking photo of small portable air compressor. I think the photo that I used is much cleaner and neater, and more representative of the thousands of compressors in industrial use. If anyone has a better one in color, that would be better yet. - mbeychok 08:03, 19 January 2007 (UTC)

How do Thermal expansion or Decompression relate to Gas compressor ??
I think that some of us get carried away with providing Wiki links. I just read the Thermal expansion article very thoroughly. It is obviously about the thermal expansion of liquids and solids. I fail to see any relation between that article and this article on Gas compressors. The lead-in sentence of this article about gas compressors states: A gas compressor is a mechanical device that increases the pressure of a gas by reducing its volume.

An article about the thermal expansion of liquids or the thermal expansion joints in bridges and railroads has no absolutely no beneficial connection whatsoever with this article. Wiki links in the "See also" section are meant to point the reader to related articles with some real, beneficial connection to gas compressors.

I also feel the same is true of the link to the Decompression article. It has no connection to gas compressors. I think it behooves all of us, myself included, to be more careful about adding unrelated links to the "See also" section of any articles. What do others think about this subject? - mbeychok 00:36, 29 January 2007 (UTC)

Split air conditioner compressor
We want to know about Split Air Conditioner Compressor. Whether it is Vapour compressor. —Preceding unsigned comment added by 220.226.5.225 (talk • contribs) 2 May 2007 (UTC)

 * If it is compressing a gaseous refrigerant, then it is indeed a gas or vapour compressor. - mbeychok 15:37, 2 May 2007 (UTC)

Air end (also spelled as airend)
This is a compressor-related term. Can someone tell me what exactly means? —Preceding unsigned comment added by Mazarin07 (talk • contribs) 26 May 2007 (UTC)

 * A packaged air compression system or a field-installed air compression facility includes a number of components: a control panel, a motor or other driver, a suction air filter, the air compression chamber, a discharge air-lubricant separator, compressed air after-cooler, lubricant cooler, compressed air dryer, compressed air filter and a compressed air receiver vessel. The air end is the air compression chamber. See Improving Compressed Air System Performance and scroll down to page 8 of 128. - mbeychok 19:09, 26 May 2007 (UTC)

Turkish Wikipedia user Metal Militia has been giving wrong information on "Compressor" subject in Turkish version
In Turkish version of Wikipedia free Enclylopedia, the "Kompresör" subject (in English "Compressor") your some internal users (of Vikipedi/Turkey) like a guy with Metal Milia nick name and some others, have been spoiling correct information and redirecting the Compressor subject to gas compressors wrongly.

Many times i had corrected the mistake and i had written Compressor subject in Turkish with my 17 years experience on Compresssor production and technical document translation.

I had written a very good atricle and simple but detailed information and explation of compressors, air compressors with my own world and private informtion as free support article to Wikipedia project as i had noticed on the article.

I had prepared the article a mixcing of my expereience and full original principles and information from leading compresıor manufatures. But article was full free and original by me. it was not a copy/paste or copyright violation.

(refencences: BCAS Compresssed Air Guide, Compressed Air Compendium, Turkish Mechanical Engineers Chamber Book "compressors", Compair BroomWade, Cooper Cameron etc. compressor manufacturer's common/publich product information. And of cource, full original information by me... as private..)

I am sure my article was 100% correct and no body could say it as wrong information or details.

At first, somebodies who say we are competent of turkish vikipedia, detletd my article and put a wrong or defective information instead of it.

They wrote me, you did not notice your information page -article- has GNU GPL. I wrote them, my article is full free by me... I tis nly by me... Ther is not need to declare GNU GPL because of wikipedia author of information is me, and it is only a wikipedşia subect there is no copy of it in anywhere expet wikipedia itself...

Even if I say, my article is recent best explanation in compressor subject in Turkish, you must support it with images and other corrections.

due to possible competition purpose (to prevent common access to information by me) -these guys may be working for competitor companies in Turkey which are manufactiring compressors as comperetior to the company which i am working for...) [ Even if i dont do advertisment of the comany... They -may be- want to prevent customers access to me by this article... ]

"kompresör" keyword is under common advertisment request in google search motor. And turkish "kompresör" subject of wikipedia encylopedia is on the first page of the searched/found pages.

Before they spoiled the article... It was a link to my non-professional web ste sections in non-profession singlix web site. These web pages have information about compresors and compressed air.

So, at the beginning of the compretition attack they erased thesinglix web site kompresor section link on wikipedia "kompresör" article...

Then they eraded the complete arti,cle and they put a wrong and short (defective) article instead of full usefull information on engineering level. The current information is just a like a first school explation of compressors. But, we know the information oabout compressors is needed by engineers and technicians, commonly... (Compressor information is not a first school or children lesson subject, so it was prepared by experinced engineers.)

I am an experienced mechanical engineer and expert on Compressors and compressed air subjects.

I am very sad due to somedies deleted my article without honesty or without sicientific/technologic correction requirements.

In Turkey, usually, non qualified and non sufficent people have competent rights. Just as yout turkish vikiedy editors (competent users) Metal Militia and others who write compessor or gas compressors article without what is compressors and gas compressors, enoughly.

Please interfe to turjish vikipedi project against the wrong staff employment/organizationing/building.

Also, i would like to see correct information on "kompresör" subject just as i had written on/about it. on Wikipedia pages...

Regards... Erdogan Tan Retrieved from "http://en.wikipedia.org/wiki/Talk:Compressor" —Preceding unsigned comment added by 85.97.52.210 (talk) 19:36, 24 October 2007 (UTC)

conservation of energy
one thing we should keep in mind, all gaseous and liquid compression / expansion processes are governed by the energy equqtion.

NAVER STOKES EQUQTION gives us the basic parameter matrex by which we play to simplefy our game. 193.191.219.80 (talk) 09:22, 14 May 2008 (UTC)

Error in "Axial-flow Compressor" section?
The section says:
 * "The rotating aerofoils, also known as blades or rotors, decelerate and pressurise the fluid. The stationary aerofoils, also known as a stators or vanes, turn and decelerate the fluid; preparing and redirecting the flow for the rotor blades of the next stage."

Shouldn't it say (in the first sentence) that the rotating blades accelerate the fluid? 24.6.66.193 (talk) 04:34, 29 June 2008 (UTC)
 * You are correct, that is an error. I have revised that sentence. Good catch! - mbeychok (talk) 06:01, 29 June 2008 (UTC)

Actually, you can say both: the rotor does decelerate the fluid in the rotating frame of reference (i.e. relative to itself) if it didn't you would need a lot more stages for the same pressure rise. It also normally accelerates the flow in the stationary frame of reference (but it doesn't have to, that depends on the angle the flow enters and exits the rotor).

 * Of course, if someone thinks they can say that in easy to understand English...AlekH (talk) 21:16, 1 July 2008 (UTC)

OK?
Is this line OK: "The inter-stage coolers cause condensation meaning liquids eg, water, gas condensate separators, known as scrubbers, with level control & drain valves are present. " 220.227.165.210 (talk) 09:50, 15 September 2008 (UTC)

 * You are correct ... that sentence is rather incoherent. In fact, the whole section was incoherent and poorly structured. Too many cooks in the kitchen. I have re-written the entire section and made it more coherent (I hope). mbeychok (talk) 04:59, 16 September 2008 (UTC)

Guided Rotor Compressor & Rolling Piston Compressor?
Anyone familiar with a compressor type called a guided rotor compressor?

I found a reasonablly detailed description of what sounds like a new compressor technology at http://www.grcompressor.com/ while researching a rolling piston compressor. The GRC is described as being similar to a Wankle engine design, but using a "envoluted trochoid". Rolling piston designs are getting significant attention in the literature, the guided rotor compressor I find less on.

Burt Harris (talk) 23:38, 5 June 2009 (UTC)

Optimal efficiency
Having read some articles online, I was lead to believe that using a very powerful (in HP) compressor and having it operate at a lower capacity than what it's capable of would yield a more favorable energy efficiency (see charts at http://oee.nrcan.gc.ca/industrial/equipment/compressed-air-ref/page-05.cfm?attr=5 ) However, this chart: http://blog.ringpower.com/?tag=/air+compressor seems to state otherwise.

Exactly how is a compression system optimally made ? What type is the best compressor (I assume the one with the best compression ratio) and at what capacity should it operate on (ie 70% ?, 100% ?, less than 70% ?) Also, how is the capacity be calculated (ie does change if you attach another motor, or does the dimensions of the compressor itself dictate a specific power range to the motor ?) How does "flow rate" fit into this (I read that there is an optimal dimension (inlet hole/outlet hole size, ...) depending on the compression ratio you wish to achieve. Finally, does ie a two stage compressor requires 2 compressors (which would be costly); or can a single compressor and two chambers be used instead ?

http://www.locostusa.com/forums/viewtopic.php?f=4&t=4538&start=45 (compression requirements dictating compressor size for optimal effiency ) http://www.grc.nasa.gov/WWW/K-12/airplane/thermo1f.html (--> formula's to calculate optimal design of compressor ?) http://www.grc.nasa.gov/WWW/K-12/airplane/compth.html

91.182.23.252 (talk) 14:10, 24 July 2011 (UTC)

 * The chart at http://www.sullairinfo.com/industrial/tandem_200804/LIT_TS_TS01E.pdf seems to verify that when using a compressor under capacity, the efficiency is lower; using "variable speed drive" increases efficiency --> does this means using gears or is the RPM of the electric motor simply hightened/lowered ?

14:59, 25 July 2011 (UTC) — Preceding unsigned comment added by 91.182.231.108 (talk)

 * BTW: the images at http://www.sullairinfo.com/industrial/tandem_200804/LIT_TS_TS01E.pdf and http://www.tpub.com/content/NAVFAC/mo206/mo2060037.htm also makes me wonder on the cost/efficiency of using different compressors for each stage (ie a rotary vane compressor could be used for stage 1, followed by a screw compressor for stage 2 or 3). This way, the purchase cost of the devices can be lowered.

91.182.231.108 (talk) 15:03, 25 July 2011 (UTC)

 * Basically any air compressor or hydraulic pump is below efficiency when underloaded, because the end result is that excess pressure is being vented off through a pressure relief valve.

 * Also, if the load working pressure is higher than the actual supplied pressure, energy is wasted getting the pressure way up high, then regulating it back out at a lower pressure. It is much more economical for the system to only provide an output that is sized to match the load required and not much greater.

 * The question is more one of "is it better to continuously supply 1000 watts, only use 100 watts, and blow the excess off through a 900 watt resistor bank, ..... or to just supply 100 watts to a 100 watt load?"

 * This is not an easy problem to solve for variable or intermittent loads.

 * DMahalko (talk) 16:35, 26 July 2011 (UTC)

"Un-noteworthyness of quasiturbine"
It seems that the quasiturbine for use as a compressor -entry seems to be removed by Andy Dingley. See http://en.wikipedia.org/w/index.php?title=Gas_compressor&oldid=441172211 Given that it's a 80% efficient motor, it should be a very efficient compressor aswell, so simply stating that it's "un-noteworthy" is quite frankly nothing less than an insult to the Saint-Hilaire family. 91.182.253.231 (talk) 16:20, 26 July 2011 (UTC)

Link to in-depth articles
I suggest adding a link to still orphan article Crankcase heater. Bglazar (talk) 14:18, 21 October 2012 (UTC)
 * Why? It's relevant to air conditioning and refrigeration, but not to compressors in general. Andy Dingley (talk) 15:48, 21 October 2012 (UTC)

Normal and standard temperature and pressure
The line saying "Sometimes the capacity of the compressors is written in NM3/hr. Here 'N' stands for normal temperature pressure (20°C and 1 atm ) for example 5500 NM3/hr", is incorrect. The N stands for Normal, meaning standard temperature and pressure, which is at 0°C not 20°C. Anyone doing compressor design can verify this. The websites I list below can also confirm this. http://www.algas.co.id/more-articles/30-general-articles/21-different-between-nm3h-sm3h-and-m3h- http://forum.onlineconversion.com/showthread.php?t=3486 Venny85 (talk) 08:39, 12 January 2013 (UTC)

 * I completely removed that sentence for these reasons:
 * The sentence was incorrectly and poorly written. NM3 should have been Nm3 and 20°C should have been 0 °C.
 * The sentence was completely out of place and out of context.
 * mbeychok (talk) 16:39, 12 January 2013 (UTC)

"Heat of compression"
"Heat of compression" is not good terminology. "Temperature rise from compression" is better. Work is done on the gas, changing the state, and the temperature is a property of the new state. This can and is usually done without the addition of heat. After compression, the gas could be isentropically expanded, and work could be produced without heat transfer. In that case, where's the heat? The answer is "there wasn't any to begin with." It's energy. Just sayin'. — Preceding unsigned comment added by 174.46.176.194 (talk) 15:43, 28 May 2015 (UTC)

"Compression of a gas increases its temperature, often referred to as the heat of compression.""

"Adiabatic - This model assumes that no energy (heat) is transferred to or from the gas during the compression, and all supplied work is added to the internal energy of the gas, resulting in increases of temperature and pressure."

As the 2nd quotation correctly asserts, no heat is involved in adiabatic compression, so the phrase "heat of compression" is a misnomer. I have removed it. — Preceding unsigned comment added by 77.96.58.212 (talk) 22:07, 15 March 2015 (UTC)

Compressor
Compressor 45.116.233.25 (talk) 11:15, 24 June 2022 (UTC)

Flow And Non Flow
Showed difference of flow and non flow compression. Astrojed (talk) 00:56, 2 February 2023 (UTC)

title: Talk:Compressor


text:
Diving air compressor

A diving air compressor is a breathing air compressor that can provide breathing air directly to a surface-supplied diver, or fill diving cylinders with high-pressure air pure enough to be used as a hyperbaric breathing gas. A low pressure diving air compressor usually has a delivery pressure of up to 30 bar, which is regulated to suit the depth of the dive. A high pressure diving compressor has a delivery pressure which is usually over 150 bar, and is commonly between 200 and 300 bar. The pressure is limited by an overpressure valve which may be adjustable.

Most high pressure diving air compressors are oil-lubricated multi-stage piston compressors with inter-stage cooling and condensation traps. Low pressure compressors may be single or two-stage, and may use other mechanisms besides reciprocating pistons. When the inlet pressure is above ambient pressure the machine is known as a gas booster pump.

The output air must usually be filtered to control purity to a level appropriate for breathing gas at the relevant diving depth. Breathing gas purity standards are published to ensure that the gas is safe. It may also be necessary to filter the intake air, to remove particulates, and in some environments it may be necessary to remove carbon dioxide, using a scrubber. The quality of the inlet air is critical to the quality of the product as many types of impurity are impracticable to remove after compression. Condensed water vapour is usually removed between stages after cooling the compressed air to improve efficiency of compression.

High pressure compressors may be set up with large storage cylinders and a filling panel for portable cylinders, and may be associated with gas blending equipment. Low pressure diving compressors usually supply compressed air to a gas distribution panel via a volume tank, which helps compensate for fluctuations in supply and demand. Air from the gas panel is supplied to the diver through the diver's umbilical.

Machinery
High pressure diving compressors are generally three- or four-stage-reciprocating air compressors that are lubricated with a high-grade mineral or synthetic compressor oil free of toxic additives (a few use ceramic-lined cylinders with O-rings, not piston rings, requiring no lubrication). Oil-lubricated compressors must only use lubricants specified by the compressor's manufacturer as suitable for use with breathing air. Special filters are used to clean the air of most residual oil and water (see "Air purity").

Smaller compressors are often splash lubricated - the oil is splashed around in the crankcase by the impact of the crankshaft and connecting rods - but larger compressors are likely to have pressurized lubrication using an oil pump which supplies the oil to critical areas through pipes and passages in the castings. Most oil lubricated compressors will have a wet sump at the bottom of the crankcase, and require the oil level to be within limits indicated by a sight glass or dipstick for proper lubrication. The compressor should also be level within the manufacturer's specification while operating. These constraints ensure that the lubricant is in the right place for either the moving parts to contact it for splash lubrication, or for reliable suction to the oil pump. Failure to comply with these specifications can lead to damage to the compressor due to excessive friction and overheating, and contamination of the breathing air by toxic breakdown products of the lubricants.

The compression process helps remove water from the gas, making it dry, which is good for reducing corrosion in diving cylinders and freezing of diving regulators, but contributes towards dehydration, a factor in decompression sickness, in divers who breathe the gas.

Low pressure diving compressors are usually single stage compressors as the delivery pressure is relatively low.

Air purity
The compressed air output by the compressor must be filtered to make it fit for use as a breathing gas. Periodically, the air produced by a compressor must be tested to ensure it meets air purity standards. Frequency of testing, contaminants that must be analysed, and the allowable limits vary between applications and jurisdictions. The following impurities may be checked for:
 * Carbon dioxide –
 * Carbon monoxide – A gas that is present in the exhaust gas of internal combustion engines, including those often used to drive compressors. It also comes from the breakdown of lubricating oil when compressors run too hot. Carbon monoxide is odorless, colorless, and tasteless. It is deadly even in small quantities, because it readily binds with the hemoglobin in red blood cells and thus destroys the blood's ability to carry oxygen. Breathing air compressors must be carefully designed and placed so that the compressor's intake is located in fresh air well away and upstream from any engine exhaust.
 * Lubricating-oil vapour – Oil, which must be used to lubricate the compressor's internal parts, can be harmful if it contaminates the breathing gas and is inhaled as a mist. Petroleum-based oils cannot be absorbed and metabolized by the body and will coat the internal surfaces of the lungs, causing a condition known as lipoid pneumonia and leading to asphyxiation and death. For this reason, compressors must be carefully designed and maintained to ensure that oil contamination of the breathing gas is within safe limits. Oils used should be approved by the compressor manufacturer and rated as safe for breathing air compressors. A range of mineral based and synthetic oils are supplied by several lubricant manufacturers for this application.
 * Total hydrocarbons –
 * Nitrogen dioxide –
 * Odor and taste –
 * Solid particles –
 * Water vapor – Allowable limits for moisture content depend on pressure: Moist air is not harmful to the diver and reduces dehydration, so is acceptable in low pressure breathing air for surface supply in much higher concentration than for storage in high pressure cylinders, where corrosion due to condensation is a problem, and where regulator freezing may occur.

Filtration
[[File:HP compressor schematic.png|thumb|upright=1.5|Schematic diagram of a three-stage high pressure breathing air compressor: F1: intake filter

1: first stage piston

C1: first stage cooling coil

OP1: overpressure valve

2: second stage piston

C2: second stage cooling coil

S1: second stage water serparator

OP2: overpressure valve

3: third stage piston

C3: third stage cooling coil

S2: third stage water separator

F2: main filter stack

OP3: overpressure valve

BP: back-pressure valve

G: pressure gauge

W: filling whip]] Filters remove:
 * Solid particles from intake air, using paper filters
 * Water, using water separators, silica gel, activated alumina or a molecular sieve
 * Oil, using activated carbon or a molecular sieve
 * Carbon monoxide, using a catalyst (Hopcalite)
 * Carbon dioxide, using a prefilter (scrubber) may be necessary depending on intake air quality.

Low pressure filtration
The intake air for a high pressure compressor should be clean and have a low carbon dioxide content. Removal of particulate contamination is usually by a paper type dust filter at the first stage intake. Carbon dioxide can be removed by a scrubber if necessary. Clean fresh air does not need to be scrubbed at present, but inner city air may have an excessively high carbon dioxide content, and standard atmospheric air carbon dioxide content is slowly increasing. Carbon dioxide scrubbing requires moisture for the absorbent material to work effectively, and moist air is undesirable for the other filter media, so carbon dioxide scrubbing is often removed by a pre-filter system before the air is compressed.

High pressure filtration systems
When the air is compressed, the partial pressure of water vapour is proportionately increased. The air is also heated by compression, and when cooled between stages in the inter-cooler coils, the relative humidity increases, and when it exceeds 100% will tend to condense out onto the surface of the tubes and as droplets carried by the air-stream. The air from the inter-cooler coils is led into the large diameter vertical axis tube of a separator, where it changes direction by about 90 degrees and is slowed down considerably. When the airflow changes direction towards the outlet at the top of the separator casing, the denser droplets have a tendency to hit the walls and coalesce into a film, which will flow downwards to the bottom of the separator and collect there where it can be periodically discharged through a drain valve. This reduces the water content of the outlet air, which is then compressed again in the next stage cylinder, cooled again, and the water that condenses out is again removed by the next separator.

After final stage separation the relatively droplet free but humid air passes through the filter to remove yet more water, and any other contaminants that the filter media will adsorb. The efficiency of dehumidification and filtration depends on significant compression and limited flow velocity, which requires back-pressure at the final stage outlet to resist flow when the filling pressure is low. The back-pressure valve provided in the outlet from the final filter stack affects how effectively the filter works.

The final stage of air treatment is filtration of residual moisture, oil and hydrocarbons, and where necessary catalytic conversion of carbon monoxide. All of these depend on sufficient time in contact with the filter media, known as "dwell time", so either the filter must have a long air path or the air must flow slowly. Slow air flow is easily achieved by high compression, so filtration works best at or near the working output pressure of the compressor, and this is achieved by the back-pressure valve, which only allows air to flow out of the filter above the set pressure.

The filter system comprises one or more pressure vessels known as filter towers with either prepacked cartridge or loose filter media, a back pressure valve, one or more pressure gauges, and a coalescing separator. After passing through the final intercooler coil the compressed air passes through separators to mechanically remove condensed water and oil droplets, after which other contaminants re removed in the filters by chemical bonding, absorption and catalysis. The first filter medium is desiccant, as water contamination can reduce the effectiveness of some of the other media. Next is the carbon monoxide converting catalyst (if used), then activated carbon, and finally a particulate filter, which will also catch dust from the filter media. The ratio of desiccant to activated carbon will be somewhere around 70/30.

The ability to remove impurities from the air passing through the filtration media is largely dependent on how long the air remains in contact with the media while passing through the filter stack, known as dwell time. A longer dwell time in the filter is an effective way of increasing contact time, and this is proportional to the pressure of the air in the filter housing. By using a back pressure valve the air always takes approximately the same time to pass through the filter and filtration is consistent (assuming a consistent operating speed). The back-pressure valve is usually set to near the working pressure of the compressor to ensure that the air is compressed sufficiently for the filters to work effectively.

Delivered air should have a dew point lower than the operational temperature of the cylinder, which is generally above 0°C when immersed, but can be colder during transport. Air temperature is also decreased during expansion through the regulator when in use, and when this temperature is low enough for the condensate to freeze, it can lock up the moving parts of the regulator and cause a free flow, known as internal icing. Correct back-pressure also provides relatively even loading of the compressor stages, which reduces vibration caused by imbalance, and extends the compressor service life.

The activated carbon filter medium works best when dry, so it is usually loaded into the filter stack so that the air will first flow through the desiccant media, commonly molecular sieve. Hopcalite catalyst will convert carbon monoxide into carbon dioxide, but requires very dry air—relative humidity must be below 50 per cent—so hopcalite is loaded downstream from the desiccant. A carbon dioxide absorbent may be loaded downstream of the hopcalite.

Filtration media
Desiccants are intended to absorb water vapour. Desiccant media used in HP breathing air filters include: activated alumina, silica gel, sorbead, and molecular sieve. Some grades of molecular sieve can absorb up to 23% of its own weight in water, can produce dew points of -75 °C, and have additional capacities for absorbing hydrocarbons, carbon dioxide, and other organics, and function at up to 49 °C120 degrees Fahrenheit.

Manganese dioxide based catalysts (Monoxycon and Hopcalite 300) are used to oxidize carbon monoxide into much less toxic carbon dioxide. This is important if there is a risk of carbon monoxide contamination as it is highly toxic. The air entering the catalyst layer must be dry (dew point of around-46 °C –50 degrees), as moisture neutralizes the catalyst. After the catalyst, an absorbent can be used to remove the CO2.

Activated carbon absorbs both condensable and gaseous hydrocarbons, and is effective in removing odours, organic compounds, and halogenated solvents.

Compressor balance and the backpressure valve
The last part of the compressor gas circuit is the back-pressure valve. This is a spring-loaded valve that opens to allow flow of air only after the pressure reaches the set pressure. It is usually set to a pressure close to the working pressure of the compressor, and has two basic functions. Firstly it ensures that after a short starting period, all of the compressor stages are operating at their designed discharge pressures, so that the loads on the pistons are steady and evenly distributed round the crankshaft. This is the loading at which the compressor is balanced at the designed running speed. When the pressure in any cylinder is different from the nominal pressure, the loads will be unbalanced and the compressor will vibrate more than when balanced, and the shaft bearings will be more severely loaded and will wear faster. During start-up the compressor first builds up pressure on the first stage, and is unbalanced, with a greater load on that cylinder's piston, and will vibrate more than normal, as there is no equivalent load on the other stage pistons, then pressure in the other stages builds up in sequence, until all cylinders are operating at their working pressures, the loads on all the pistons are similar, and the back-pressure valve starts to open to let the compressed gas flow to the distribution panel.

Pressure
Diving compressors generally fall into one of two categories: those used for surface-supplied diving and those used for filling scuba diving cylinders and surface-supply storage cylinders.

Surface-supplied air diving compressors are low-pressure and high-volume. They supply breathing air directly to a diver, through a gas control panel sometimes called a "rack" via a hose which is usually part of a group of hoses and cables called an "umbilical". Their output is generally between 6 and 20 bar. These compressors must be sufficiently powerful to deliver gas at a sufficient pressure and volume for multiple divers working at depths of up to about 60 m.

Compressors used to fill scuba cylinders have a high delivery pressure and may have a low delivery volume. They are used to fill diving cylinders and storage cylinders or banks of storage cylinders. These compressors may be smaller and less powerful because the volume of gas they deliver is not so critical as it is not directly used by the diver; a lower volume compressor can be used to fill large storage cylinders during the periods when demand is low. This stored compressed air can be decanted into diving cylinders when needed. Common scuba diving cylinder pressures are 200 bar (2940 psi), 3000 psi (207 bar), 232 bar (3400 psi) and 300 bar (4500 psi).

Heat of compression
When diving cylinders are filled the gas inside them warms as a result of adiabatic heating. When the gas cools by losing heat to the surroundings, the pressure will drop as described by the general gas equation and Gay-Lussac's law. Divers, to maximise their dive time, generally want their cylinders filled to their safe capacity, the working pressure. To provide the diver with a cylinder filled to the working pressure at the nominal temperature of 15 or 20 °C, the cylinder and gas must be kept cool when filling or filled to a pressure such that when it cools it is at the working pressure. This is known as the developed pressure for the filling temperature. Health and safety regulations and pressure vessel design standards may limit the working temperature of the cylinder, commonly to 65 °C, in which case the cylinder must be filled slowly enough to avoid exceeding the maximum working temperature. Cylinders are often filled at a rate of less than 1 bar (100 kPa or 15 lbf/in²) per second to allow time for heat transfer to the surroundings to limit this increase in temperature. As a method to remove heat faster when filling the cylinder, some filling stations “wet fill” cylinders immersed in a bath of cold water. There is an increased risk of internal cylinder corrosion caused by moisture from the wet environment entering the cylinder due to contamination during connection of the filling hose during wet filling.

The bank
Compressors may be connected to a bank of large, high-pressure cylinders to store compressed gas, for use at peak times. This allows a cheaper low-powered compressor, which is relatively slow at pumping gas, to fill the bank automatically during idle periods, storing a large volume of pressurized air so that a batch of cylinders can be filled more quickly at peak demand without being delayed by the slow-running compressor. In surface-supplied diving, high-pressure cylinder banks may be used as an emergency backup in case of primary compressor failure, or they may be used as the primary source of breathing gas, a system also known as "Scuba replacement".

Filling diving cylinders
Cylinders may be filled directly from the compressor outlet, or from a filling manifold, via a flexible high-pressure hose with a filling valve and purge valve known as a filling whip. A pressure gauge is provided to monitor the pressure in the cylinder as it is filled. an overpressure valve or an electrical pressure-switch may be used to limit filling pressure if the compressor is set to a higher pressure than the developed working pressure of the cylinders to be filled.

Gas blending

Compressors may be linked to a gas blending panel to make nitrox, trimix, heliair or heliox mixes. The panel controls the decanting of oxygen and helium from cylinders bought from commercial gas suppliers.

As it is not possible to decant to a diving cylinder from a storage cylinder that holds gas at a lower pressure than the diving cylinder, the expensive gas in low pressure storage cylinders is not easily consumed and may go to waste when the storage cylinder is returned to the supplier. The cascade system may be used with a bank of storage cylinders to economically consume these high cost gases so that the economically maximum gas is used from the bank. This involves filling a diving cylinder by first decanting from the bank cylinder with the lowest pressure that is higher than the diving cylinder's pressure and then from the next higher-pressure bank cylinder in succession until the diving cylinder is full. The system maximizes the use of low-pressure bank gas and minimizes the use of high-pressure bank gas.

Another method for scavenging expensive low pressure gases is to pump it with a gas booster pump such as a Haskel pump, or to add it to the intake air of a suitable compressor at atmospheric pressure in a mixer known as a blending stick.

Operation
A diving air compressor operator may be required to be formally certified as competent to operate a diving air compressor and to fill high pressure cylinders. In other jurisdictions the operator may be required to be competent to use the equipment and externally examine cylinders for compliance, but there may be no formal licence or registration required. In yet other jurisdictions there may be no control at all. National and/or state occupational health and safety legislation will usually apply.

There are two basic aspects which may be considered: The health and safety of the operator, who operates hazardous equipment, and is exposed to mechanical and noise hazard from the compressor machinery, high pressure equipment, and cylinders, and the health and safety of the user of the breathing gas, who relies on the compressor operator for quality assurance.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Diving air compressor


text:
Willard Scott

Willard Herman Scott Jr. (March 7, 1934 – September 4, 2021) was an American weather presenter, radio and television personality, actor, narrator, clown, comedian, and author, whose broadcast career spanned 68 years, 65 years with the NBC broadcast network. Scott is best known as a weather reporter on NBC's Today show where he also celebrated US centenarian birthdays and notable anniversaries. Scott was the creator and original performer of McDonald's mascot clown Ronald McDonald.

The 6' 3", 290 lb. (6 ft, 290 lb) Scott was described by The New York Times as a "garrulous, gaptoothed, boutonnière-wearing, funny-hatted, sometimes toupee-clad, larger-than-life American Everyman". Scott parlayed his national exposure as weather presenter into a highly successful career as a pitchman who promoted an ever-widening range of products the fees for which outstripped his million dollar annual salary at NBC (equivalent to $ in ). Scott said "I run me like a conglomerate, because that's what I am. I always keep lots of balls in the air".

Scott credited his success to his efforts to make everyone, his audience, his clients feel loved. Scott said "If you watch, you’ll see that I am trying to weave a web of love. I want to make the whole country feel as if we are one. I may be a cornball, but I am me — not a sophisticated, slick New York wazoo act." Early radio contemporary Johnny Holliday, said of Scott "Everybody he came in contact with just loved the guy. He just had that magic about him, that he made everybody feel special."

In Scott's autobiography The Joy of Living he summed his life, saying "If you were to look at my resume, you’d see that I’m ...bald, I’m overweight, I don’t make all the smooth moves and I dress like a slob. I take tremendous pride in the fact that I beat the system".

Early life and education
Scott was born on March 7, 1934, in Alexandria, Virginia, the only child of parents Willard Herman (1905—1977) and Mattie Thelma (née Phillips) Scott (1905—1977). Scott was raised as and remained a fundamentalist Christian who considered becoming a minister before starting his broadcasting career.

Childhood interest in broadcasting
Scott showed an early interest in broadcasting. Recounting his first experience visiting a radio station, he said "One day when I was eight, Mom took me to the movies in DC. Afterward, she wanted to shop, so I wandered over to my favorite radio station, WTOP. I introduced myself to the receptionist and told her I was a fan. She took me to the control room and said, 'You can sit here if you stay very quiet. That man will be broadcasting live'. The man was Eric Sevareid, then a correspondent for CBS. He’d just gotten back from Burma, where he’d been lost in the jungle for months. I sat there enthralled as Sevareid recounted his ordeal".

At the age of nine, Scott organized a group of 15 boys into a radio club on his neighborhood block. Scott built his own radio station in his family home's basement and sold ads he aired during his low power broadcasts. The club netted about $25 a month in advertising revenue from neighborhood businesses. Scott said "...I set to work building a station in our basement. My parents bought me an oscillator, which enabled me to broadcast to 20 neighborhood homes within a 180 foot radius. My friends and I read the news, played tunes on a phonograph, and chattered away. A few months after we started, three men from the FCC showed up. They told us our signal was reaching National Airport — Pan Am’s radios were picking up kids talking and playing records. So ended my basement station".

Spending time at local Alexandria radio station WPIK-AM on Friday nights as a teenager, a local disk jockey allowed him to create a radio show called "Lady Make Believe". Scott also served as announcer for the show. Scott also held two part-time disk jockey jobs while in high school, "High School Hit Parade" on WOL 1450 AM and "Dancing Party" on WCFM 99.5 FM.

NBC radio announcer at 16
Scott was 16 years old in 1950 when he worked as an NBC page at WRC (AM), NBC's owned-and-operated radio station in Washington, D.C., for $12 per week. Scott explained how he started announcing at NBC – "I auditioned to be an announcer but was never hired. Then one of the announcers left for vacation and my boss said, 'What the hell, let Scott fill in — it’s only two weeks.' When he returned, I became a regular substitute".

High school and college
Scott attended Alexandria, Virginia's George Washington High School. While a freshman in 1947, Scott broadcast a high school news report on a local FM radio station every Saturday. Scott graduated high school in 1951. He was elected class president all four years of his attendance. Named "Our capable and popular class president", he was also voted "Most Likely to Succeed" by his classmates.

Scott attended American University, where he worked alongside fellow student Ed Walker at WAMU-AM, the university's radio station (1951—1953). Scott became a member of Alpha Sigma Phi fraternity while at American University and graduated in 1955 with a Bachelor of Arts degree in "philosophy and religion".

Joy Boys radio show
From 1955 to 1972, Scott teamed with Ed Walker as co-host of the nightly Joy Boys radio program on NBC-owned WRC radio (this was interrupted from 1956 to 1958 when Scott served on active duty in the U.S. Navy). Scott routinely sketched a list of characters and a few lead lines setting up a situation, which Walker would commit to memory or make notes on with his Braille typewriter (Walker was blind since birth).

The show opened with Scott and Walker singing their Joy Boys opening theme song set to the music of John N. Klohr's The Billboard March. They recorded it in two versions, a duet between them, and Walker singing in four-part harmony with himself, for use as, respectively, the opening and closing themes for the show:

We are the Joy Boys of radio; We chase electrons to and fro-o-o. We are the Joy Boys of radio; We chase electrons to and fro.

In a 1999 Washington Post article recalling the Joy Boys at the height of their mid-1960s popularity, said the Joy Boys "dominated Washington, providing entertainment, companionship, and community to a city on the verge of powerful change". The Joy Boys broadcast on WRC until the station changed to a rock music format in October, 1972. The Joy Boys show moved to WWDC-AM for another two years. Scott wrote in his book The Joy of Living, their close professional and personal bond continued until Walker's death in October 2015. Scott said they were "closer than most brothers".

After the Joy Boys show ended, Scott thrived as a Washington D.C. area personality, doing product pitches and popping up at ribbon-cutting ceremonies.

WAVY AM 1350 disk jockey while in the Navy
In 1956 Scott lived near Norfolk, Virginia while serving in the U.S. Navy and moonlighted at WAVY AM radio as one of four staff disk jockeys who presented the "WAVY Nifty Fifty, Tidewater's Top Tune Tally.". He was promoted on local advertising for the Tidewater area radio station.

Children's programs a great preparation for television success
Scott felt his early work in children's programming was one reason for his success in engaging and entertaining television viewers. "I have always said that the best training to be a TV newsman or anybody on television is to do a children’s show because you are oblivious to the fact that there is a camera there. ...You are playing to the kids in the studio, and then you are playing directly to the kids at home. You look in the lens and you are never using a teleprompter ...and you get a tremendous, comfortable feeling in front of a camera doing a children’s show. There are no two ways about that: Doing a kid’s show is great training."

Barn Party
Scott's first children's television appearance was on WNBW TV's Barn Party in 1954. Scott said "My first chance to do kiddie shows professionally came before I was in the Navy, on a Saturday TV show called Barn Party. I was 'Farmer Willard' and I played opposite a very refined lady named Betsy Stelck, who had a fairyland aura about her..." The show was a hit. When children were asked to mail in requests for tickets to attend the weekly broadcast production, 6,223 requests were received. The studio only seated 50.

Afternoon
Scott was a "co-master of ceremonies" with Mac McGarry on this 1955 afternoon variety program broadcast on WRC-TV. The show featured live music, vocalists, fashion and food segments by Inga Rundvold and Jim Henson's puppet group Sam and Friends, an early incarnation of the Muppets. At the time, Henson was a college freshman. Scott remembered Henson's work as "... an innovative bunch of puppets created by a guy named Jim Henson. ... I worked with a bald-headed Muppet with a big nose, named Sam, sort of the way Fran Allison worked on Kukla, Fran and Ollie. Then there was the frog named Kermit. I used to do a commercial for a local peanut butter called Schindler's. He'd open his mouth, I'd give him a big spoonful, and he'd go 'ahh'".

Commander Retro
Scott said this 1966 children’s show he created and hosted was "The worst show I did in my life, in my opinion, was the best show I ever did in my life, we had more fun". Scott used Lester, his basset hound, as "Doctor Strangedog", a human German physicist and spy who had stowed away on the rocket ship. The spy had eaten too many hotdog sausages, exploded and turned into a talking dog. Scott played the commander of their traveling spaceship. The rocket ship set had control panels made of plastic mini-ice cube trays with blinking Christmas lights behind them. Scott said "This was a terrible show, a real turkey ...but it was more fun to do than any of them".

Bozo the Clown
Scott portrayed Bozo the Clown on WRC-TV's one-hour, weekday show Bozo's Circus. Scott said "WRC bought local rights to Bozo the Clown, and I was cast in the role. Bozo went to the White House and met JFK and Caroline. I played him from 1959 to 1962, doing a daily one-hour show". Washington, D.C., area McDonald's hired Scott – as Bozo – to attract customers. Whenever Scott as Bozo arrived at one of the then five D.C. area McDonald's, he caused traffic jams. Roads were shut down for two miles and extra police had to control thousands of kids as they arrived to see Bozo. WRC-TV canceled the show in 1962.

Created Ronald McDonald, the Hamburger-Happy Clown

Washington, D.C., McDonald's stores had enjoyed incredible customer attendance when Scott appeared as Bozo the Clown. When WRC-TV cancelled the show, Scott could no longer appear as that popular clown. The local McDonald's franchisees wanted another clown to drive sales and asked Scott to develop a new character. Scott said "At the time, Bozo was the hottest children's show on the air. You could probably have sent Pluto the Dog or Dumbo the Elephant over and it would have been equally as successful. But I was there, and I was Bozo... There was something about the combination of hamburgers and Bozo that was irresistible to kids... That's why when Bozo went off the air a few years later, the local McDonald's people asked me to come up with a new character to take Bozo's place. So, I sat down and created Ronald McDonald".

Scott's Ronald McDonald costume included a small paper cup over his nose, a cardboard food tray worn as a hat and a cardboard food tray containing a complete McDonald's meal - a wrapped hamburger, paper bag of fries and a drink, worn just above the front of his pants that “magically” replaced the hamburger every time one disappeared. Scott portrayed Ronald McDonald from 1963 through 1967, appearing in three television commercials and narrating a 45 rpm recording of "The Night Before Christmas" as part of a 1963 holiday promotion. The record has become a sought-after collectible.

McDonald's corporation purchased the Washington, D.C., franchise back from the area franchisees and became the owner of the Ronald McDonald intellectual property. Scott was told he would continue to portray the clown but just before he was to appear at the 1966 Macy’s Thanksgiving Day Parade, Scott was replaced by a new clown actor, Coco, who had been a clown in the Ringling Brothers circus.

In his book Fast Food Nation, Eric Schlosser claims that McDonald's replaced Scott on account of his weight, supposedly concerned about McDonald's image. Scott denied the claims and cited other commitments he had at the time.

The Ronald Show
Scott continued to appear as Ronald McDonald in the Washington, D.C., broadcast market. In 1966, Scott served as master of ceremonies WRC-TV's new program, The Ronald Show. The show had a studio audience of 30 youngsters every Saturday who played games, performed dramatic skits and interacted with Scott as clown Ronald. Scott said the show was "One of those magnificent rare treasures ... featuring dramatizations and dance contests."

Weather presenter career
Scott's weathercaster career started when he was chosen as a fill-in weatherman on WRC-TV in 1967. The incumbent had suddenly walked off the job. In 1970, Scott became WRC-TV's full-time weekday weatherman. In March 1980, the NBC network came calling, and Scott was named  weatherman on TODAY, replacing Bob Ryan. Ryan then took Scott's old job, becoming the meteorologist at WRC-TV.

The Today Show

Scott was tapped by NBC in 1980 to become its weatherman for The Today Show. At the time, the Today Show was in its first ratings battle with ABC's Good Morning America. Scott quickly established his ability to connect with his audience. Often appearing as different characters in his segments, he once delivered the weather as pop singer Boy George. His antics on Today helped move the show's ratings back to first place, where it remained for much of the decade.

During the 1980s, Scott routinely did weather reports on the road, interviewing locals at community festivals and landmarks. He also periodically performed on the program from Washington, D.C., which he still considered his home.

Appearance as Carmen Miranda
Scott said he used to dress up like Carmen Miranda as a kid to sell war bonds in World War II. He promised to don a Miranda outfit again if a viewer would donate $1,000 to the USO. The donation was made and Scott gave his August 22, 1983, weather forecast on the Today Show dressed in drag, wearing a bright red tropical dress, earrings and pearls, heels, and a showy, multi-colored headdress with feathers and fruit, reminiscent of the late Brazilian entertainer's outfits. Scott's weather forecast was accompanied by two flamenco musicians.

Discussing his Carmen Miranda appearance in 1987, Scott told the New York Times "People said I was a buffoon to do it. Well, all my life I've been a buffoon. That's my act." He explained his love for his audience, saying "I just love people. A lot of speakers on the talk circuit leave right afterward. I do a lot of schmoozing. I'm like a dog. You just open the door and I go, 'rrrr, rrrr,' and then I lick everybody's face."

Smucker's birthday segments
Scott started celebrating centenarians' happy birthdays on “Today” in 1983. "Saluting people on their 100th birthday started when I got a card that read, 'My uncle is turning 100. Could you mention him on TV?' I did it and about a week later got two cards, then four, then six." Eventually Smucker's sponsored the segment, showing each person’s photo and name on a Smucker's strawberry jelly jar label. When Scott died, Smucker’s posted a tribute to him, putting his face on the jelly jar label graphic.

Bryant Gumbel criticism and ratings repercussions
In 1989, The Today Show co-host Bryant Gumbel wrote an internal memo critical of the show's personalities, a memo that was later leaked to the media. In the memo, Gumbel said Scott "holds the show hostage to his assortment of whims, wishes, birthdays and bad taste ...this guy is killing us and no one's even trying to rein him in." This garnered enough of a backlash that the next time they appeared on camera together Scott kissed Gumbel on the cheek to show he'd forgiven him, and also later said he hoped the whole thing would go away.

After Gumbel's comments, there was a decline in viewership ratings for the Today Show. According to NBC, the Q Score popularity tracking poll taken by Marketing Evaluations Inc. showed an increase in negative reaction to Gumbel and his earlier criticism of Scott in its annual May 1989 survey of the show. The then Today Show executive producer Tom Capra said "The publicity and the negative factors have hurt us". CBS network research also indicated continuing negative reaction to Gumbel's comments regarding Scott.

Today Show staff support
After Scott's Carmen Miranda appearance, Tom Brokaw, former Today Show anchor said of Scott, "Willard was a born showman". Al Roker, the meteorologist who succeeded Scott on the Today Show said "No broadcaster was loved by so many and brought so many smiles".

Commercial pitchman
In 1992, Scott, who was the first incarnation of Ronald McDonald, recorded a commercial for McDonald's arch-rival Burger King. He also was the spokesman for the Days Inn hotel chain, appearing in their commercials from 1993 until 1997.

The companies Scott endorsed include: Howard Johnson Motor Lodges, True Value Hardware, Burger King, Lipton tea, Maxwell House coffee, the American Dairy Association, the Florida Citrus Commission, Diet Coke, USA Today and many others.

Willard Scott's Home and Garden Almanac
In 1995, Scott was the host of one of the first weekly series on the then new cable TV channel Home & Garden Television. The series ran two years.

Actor
Scott made occasional guest appearances as neighbor "Mr. Poole" on The Hogan Family, where his character was married to Mrs. Poole, played by Edie McClurg.

NASA
Scott worked as the narrator for NASA's weekly program called "The Space Story", with his contributions spanning from the Apollo Program to the Space Shuttle.

Personal appearances / TV Commentator career
Scott was the host of WAVE TV's broadcast coverage of the Kentucky Derby Festival Pegasus Parade in Louisville, Kentucky, from 1982 through 2005. Scott also hosted the NBC telecast of the Macy's Thanksgiving Day Parade from 1987 to 1997. He was replaced by Matt Lauer in 1998.

For several years in the 1980s, Scott donned a Santa Claus costume for the broadcast of the National Tree-Lighting Ceremony in Washington, D.C.

In 1990 and 1992, Scott also hosted the Pillsbury Bake-Off on CBS (while under contract with CBS' rival NBC).

Military service
Scott enlisted in the U.S. Navy, serving from 1956 to 1958 as a seaman. Then 22 years old, Scott recorded his feelings on November 23, 1956, the day before he enlisted.

Retirement
Scott went into semi-retirement in early 1996, succeeded by Al Roker who moved from D.C. station WTTG. Scott had helped Roker earn the weather job at the NBC's WKYC in Cleveland.

Scott continued to appear two days a week on the morning program to wish centenarians a happy birthday (a tradition that continues to the present day). He appeared from the studio lot of WBBH, the NBC affiliate in Fort Myers, Florida.

Scott also continued to substitute for Roker for over a decade afterward, an arrangement that mostly ended after NBC acquired The Weather Channel in 2008 and started using that channel's meteorologists as substitutes.

Scott announced his full retirement from television on December 11, 2015. On Scott's final day, Today held a tribute to Scott featuring taped highlights from his many years with the show. The plaza outside Rockefeller Center was renamed Willard Scott Way in his honor. Several former Today staff came to bid farewell to Scott including Tom Brokaw, Jane Pauley, Katie Couric, and Gene Shalit along with Barbara Bush. After Scott was feted on the "Today Show" with cupcakes and comments from co-anchors, he said "I'm fading off into the sunset" and started singing Dale Evans's song "Happy trails to you until we meet again. Happy trails to you. Keep smilin' on 'til then."

Radio reissues and Santa Claus
In 2001, American University reissued some of the old Joy Boys radio broadcasts of the 1960s on CDs. He also played Santa Claus at various White House events.

Writings
Scott published several fiction and non-fiction books:
 * The Joy of Living
 * Down Home Stories
 * Willard Scott’s All-American Cookbook
 * America Is My Neighborhood
 * The Older the Fiddle, the Better the Tune
 * If I Knew It Was Going to Be This Much Fun, I Would Have Become a Grandparent First

He also co-authored two books with Bill Crider:

 * Murder Under Blue Skies
 * Murder in the Mist

He preached a sermon at the 185th anniversary of his home church, First Baptist Church in Alexandria, Virginia, that was published in Best Sermons 2, edited by James W. Cox [Harper & Row, 1989].

Personal life
Scott was married to Mary Dwyer Scott from 1959 until her death in 2002. The couple had two children, Mary and Sally. On April 1, 2014, at age 80, Scott married Paris Keena, whom he first met in 1977 while she was working at WRC-TV in Washington, D.C. They had been together as a couple since 2003. They lived on Sanibel Island, Florida.

Death
Scott died of natural causes on September 4, 2021, at the age of 87.

As himself

 * Pillsbury Bake-Off (1990–1992) – Host
 * Walt Disney World 4 July Spectacular (1988) – Himself
 * The New Hollywood Squares (1987) – Himself
 * Kentucky Derby Festival Pegasus Parade (1982-2005) - host
 * Macy's Thanksgiving Day Parade (1987–1997) – Host
 * The Bob Braun Show (1982) – Himself
 * Today (1980–2015) – Himself

As actor

 * Bozo the Clown (1959–1962) – Bozo the Clown
 * Ronald McDonald (1963–1965)
 * The Hogan Family (1987–1989) – Peter Poole
 * Undertale (2015) - Flowey (voice sampled from Ronald McDonald commercial)

title: Willard Scott


text:
Ivan Rybkin

Ivan Petrovich Rybkin (Ива́н Петро́вич Ры́бкин; born 20 October 1946) is a Russian politician. He was Chairman of Russia's State Duma in 1994–96 and Secretary of the Security Council in 1996–1998. He has the federal state civilian service rank of 1st class Active State Councillor of the Russian Federation.

He ran for the Russian presidency in 2004, before dropping out after allegedly being kidnapped and drugged by Russian Federal Security Service (FSB) officers.

Early life
He was born in village of Semigorka, Voronesh Oblast. In 1968, Rybkin graduated from Volgograd Agricultural Institute, and in 1991 from the Soviet Academy of Social Sciences.

Political career
After a career on lower ranks of the Communist Party, Rybkin was elected as peoples' deputy to the congress of the Russian Soviet Federated Socialist Republic in 1990. In 1993, Rybkin became a member of the Agrarian Party of Russia. That very year in December, he was elected deputy of the State Duma.

Speaker of Russian State Duma
In 1994, Rybkin was elected speaker of the State Duma. In January 1995, he became a member of the Security Council of the Russian Federation. In July of that year, Rybkin became a leader of the Ivan Rybkin Bloc.

Ivan Rybkin Bloc got 1.39% of the vote in the 1995 Russian legislative election, falling short of a 5% electoral threshold. Its campaign video clip featured two cows who discussed fairness in a philosophical manner.

In March 1998, Rybkin was appointed Deputy Prime Minister for Commonwealth of Independent States affairs.

Presidential candidate and alleged kidnapping
In 2004, Rybkin was nominated by Berezovsky's Liberal Party for the Russian presidential elections. During the campaign, on 2 February 2004, he accused incumbent President Vladimir Putin of organizing terrorist acts in Russia in 1999 and of being involved in shady business activities with Yury Kovalchuk, Mikhail Kovalchuk, Gennady Timchenko, KiNEx and the Russia Bank, which allegedly swallowed up a vast share of the nation's financial flows.

Rybkin's candidacy aligned itself strongly with Berezovsky's politics. While it was believed that Rybkin would, even optimistically, be unable to receive more than 2% of the vote, it was also believed that he might receive a sizable enough amount of funding from Berezovsky that he could orchestrate a significant amount of anti-Putin campaigning in advance of the election.

Many Russians had reported themselves to be too unfamiliar with Rybkin to have an opinion on him.

In February 2004, Rybkin disappeared for four days under mysterious circumstances. A day before his disappearance he accused the Putin administration of complicity in the 1999 bomb attacks in Moscow that led to a war in the Russian breakaway republic of Chechnya. Five days later, Rybkin appeared in Kyiv. According to Rybkin's first explanations, on February 5 he decided to “take a break from the fuss” that was raised around him and went to Kyiv. Rybkin did not specify what kind of “fuss” this was. He said that he turned off his mobile phones so that his rest would not be disturbed. “I have the right to two or three days of privacy! - said Rybkin. “I often visit Kyiv, my friends and I walk the streets, especially since the weather was good there this weekend.” Later, he stated that he had been kidnapped and drugged by Russian FSB agents who lured him to Ukraine promising to arrange meeting with the former Chechen leader Aslan Maskhadov. Upon arrival he was offered refreshments in the apartment, at which point he became "very drowsy." After being unconscious, he woke up on 10 February. Upon waking, he was shown a videotape in which he was performing "revolting acts" conducted by "horrible perverts". He was told that the tape would be made public if he continued with his presidential campaign. According to Alexander Litvinenko, the FSB agents apparently treated Rybkin with their standard truth drug.

Rybkin said he feared for his safety if he returned to Russia, and whilst he initially continued the campaign from abroad, on 5 March 2004, he withdrew from the race, saying he did not want to be part of "this farce," as he called the elections.

title: Ivan Rybkin


text:
User talk:80.231.147.1

Please do not recreate pages where vfd process has agreed that they should be deleted. If you want to see the page reappear list on Votes for undeletion instead. -- Francs2000 | Talk 00:59, 11 Jan 2005 (UTC)

title: User talk:80.231.147.1


text:
Wikipedia talk:Requests for arbitration/Anthony/Evidence

What is his vote to keep Richard Genovese supposed to be evidence of? --Daniel C. Boyer 17:23, 6 Mar 2004 (UTC)

Or Sarah Marple-Cantrell for that matter. That got a lot of attention in the U.S. press. On the other hand, looking over this list suggests to me that VfD seems to be failing to get rid of obvious garbage (the Shaheen Lakhan vanity page and the How to make a Biodiesel which needs to go to Wikibooks). - Hephaestos|§ 17:30, 6 Mar 2004 (UTC)

Anthony -- don't edit other people's contributions to this page -- add a note below or something that makes it clear what your response/position is to someone else's claim. BCorr ¤ Брайен 01:56, Mar 18, 2004 (UTC)

I didn't edit, I added my own content. that whole part in parentheses was initially written by me. Anthony DiPierro 02:02, 18 Mar 2004 (UTC)

 * Can you clarify what you've added/edited in some way on the page -- if you're going to be editing this page? Thanks, BCorr ¤ Брайен 02:04, Mar 18, 2004 (UTC)

I didn't want to put this on the meta page yet, but I am guessing that today's edit war between Anthony and User:Yarko Brachini against Wik involved a sock puppet. Check out Yarko's contributions and the page history for antinomy ... BCorr ¤ Брайен 02:36, Mar 18, 2004 (UTC)
 * It could be Wik's sock puppet against Wik. You never know. Kingturtle 02:47, 18 Mar 2004 (UTC)
 * I asked you to check the server logs to see if it matches a known user. --Wik 02:49, Mar 18, 2004 (UTC)
 * Or it might not be a sockpuppet at all. Wik and I both have a list of our disputed pages on our user pages. Anthony DiPierro 02:51, 18 Mar 2004 (UTC)

I'd like to know the IP address, in any case. I guess that's not allowed, though? Anthony DiPierro 02:54, 18 Mar 2004 (UTC)

Why is it that you are involved in 90% of the edit wars on this site daily? Coincidence? Hardley. ChrisDJackson 02:56, 18 Mar 2004 (UTC)

Yarko Brachini is not Anthony. Yarko Brachini is a sock puppet of a regular contributor who is not involved with this debate, and seems to have had very little to do with Wik in recent times. The user attempted to obscure their identity while performing this uncharacteristic act of mischief, albeit imperfectly. S/he has been warned privately not to try this again. -- Tim Starling 04:38, Mar 18, 2004 (UTC)

re: Kingturtle's evidence
Anthony, Stop editing my posts. If you want to make comments then do it elsewhere on the meta page. I created a section for such comments; use that section please. Kingturtle 04:08, 22 Mar 2004 (UTC)

 * I can add comments in brackets identifying some of your lies. Adding them at the end is too confusing. Anthony DiPierro 10:43, 22 Mar 2004 (UTC)


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Maurice Spector

Maurice Spector (March 19, 1898 – August 1, 1968) was a Canadian politician who served as the chairman of the Communist Party of Canada and the editor of its newspaper, The Worker, for much of the 1920s. He was an early follower of Leon Trotsky after Trotsky's split from the Communist International.

Early life
Spector was born in the Russian Empire and immigrated to Canada with his family as an infant. He graduated from Queen's University and practiced labour law in Toronto when he was not employed in political positions.

First radical political activity
Spector was influenced by Trotsky's work The Bolsheviki and World Peace,, which was published in the Toronto Mail and Empire in January 1918 and by Social Democratic Party of Canada (SDP) Dominion Secretary Isaac Bainbridge, who introduced him to Lenin's writings and inspired him to join the SDP. Spector engaged with the left wing of the Canadian SDP and eventually left to form the Communist Party of Canada.

Turn to Trotskyism
In 1928, Spector, while attending the Sixth Congress of the Comintern in Moscow, accidentally got hold of a copy of Trotsky's Critique of the Draft Programme of the Communist International, which criticized the position of Nikolai Bukharin and Joseph Stalin and especially the theory of "socialism in one country". The critique was a landmark in the ideological arming of the International Left Opposition. In a truly-prophetic statement, Trotsky warned that if this position were adopted by the Communist International, it would inevitably mark the beginning of a process that would lead to the nationalist and reformist degeneration of every communist party in the world. Three generations later, his prediction, which was then ridiculed by the Stalinists, has been shown to be correct.

Stalin had no intention of circulating Trotsky's document, but by a strange accident of history, that is what happened. The Stalinist regime had not yet been consolidated, and the Communist International still had to observe certain norms of democratic centralism, which permitted the circulation of minority opinions. Although Trotsky had been expelled from the Russian party a year earlier, he took advantage of the Congress to appeal to the Communist International. In the process, he submitted his document on the Draft Programme. Through a blunder in the apparatus, it circulated Trotsky's document to the heads of the delegations, including members of the programme commission. It was then that the American James Cannon and Maurice Spector first saw and read Trotsky's document.

Cannon recalled:

"Through some slip-up in the apparatus in Moscow," recalls Cannon, "which was supposed to be airtight, this document of Trotsky came into the translating room of the Comintern. It fell into the hopper, where they had a dozen or more translators and stenographers with nothing else to do. They picked up Trotsky's document, translated it and distributed it to the heads of the delegations and the members of the programme commission. So, lo and behold, it was laid in my lap, translated into English by Maurice Spector, a delegate from the Canadian party, and in somewhat the same frame of mind as myself, was also on the programme commission and he got a copy. We let the caucus meetings and the Congress sessions go to the devil while we read and studied this document. Then I knew what I had to do, and so did he. Our doubts had been resolved. It was as clear as daylight that Marxist truth was on the side of Trotsky. We had a compact there and then - Spector and I - that we would come back home and begin a struggle under the banner of Trotskyism."

Spector was a founder of the Canadian Trotskyist movement, which was first constituted as a branch of the Communist League of America in 1929.

Workers Party of Canada
In 1932 he co-founded, with Jack MacDonald, the Workers Party of Canada. The new organization represented the first Canadian section of the International Left Opposition.

Leaving Canada
Spector moved to New York City in 1936 and became a leading member of the Trotskyist movement there. He presented the International Report at the founding convention of the Socialist Workers Party at the end of 1938 but dropped out of the party in 1939. (Contrary to some reports, he did not take part in the 1939-40 debate between James Cannon and Max Shachtman.)

He joined the Socialist Party of America shortly after leaving the SWP in 1939 and remained on its executive body until 1958, when he resigned after breaking with Max Shachtman and his proposal to merge Shachtman's Independent Socialist League with the Socialist Party, which Spector anticipated would move the SP to the right.

In his later, Spector became editor of a children's magazine published by the Labour Zionist movement.

Deportation threat
Canada had revoked Spector's citizenship, and in 1941, the Federal Bureau of Investigation learned that Spector was in the United States illegally and had him detained. As Canada refused to accept him, the United States began proceedings to deport him to the Soviet Union. The American Civil Liberties Union defended Spector on the grounds that as a Trotskyist, his life would be in danger if he was deported to the Soviet Union. Spector eventually regained his Canadian citizenship and was permitted to remain in New York.

Later life
Spector was employed for part of his post-Trotskyist career by the American Council for Judaism and was director of the New York trade union division of the National Committee for Labor Israel in his later years.

Spector died on August 1, 1968, at the age of 70.

title: Maurice Spector


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Nomenclature of Territorial Units for Statistics

Nomenclature of Territorial Units for Statistics or NUTS (Nomenclature des unités territoriales statistiques) is a geocode standard for referencing the administrative divisions of countries for statistical purposes. The standard, adopted in 2003, is developed and regulated by the European Union, and thus only covers the EU member states in detail. The Nomenclature of Territorial Units for Statistics is instrumental in the European Union's Structural Funds and Cohesion Fund delivery mechanisms and for locating the area where goods and services subject to European public procurement legislation are to be delivered.

For each EU member country, a hierarchy of three NUTS levels is established by Eurostat in agreement with each member state; the subdivisions in some levels do not necessarily correspond to administrative divisions within the country. A NUTS code begins with a two-letter code referencing the country, as abbreviated in the European Union's Interinstitutional Style Guide. The subdivision of the country is then referred to with one number. A second or third subdivision level is referred to with another number each. Each numbering starts with 1, as 0 is used for the upper level. Where the subdivision has more than nine entities, capital letters are used to continue the numbering. Below the three NUTS levels are local administrative units (LAUs). A similar statistical system is defined for the candidate countries and members of the European Free Trade Association, but they are not part of NUTS governed by the regulations.

The current NUTS classification, dated 21 November 2016 and effective from 1 January 2018 (now updated to current members ), lists 92 regions at NUTS 1, 244 regions at NUTS 2, 1215 regions at NUTS 3 level, and 99,387 local administrative units (LAUs).

National structures
Not all countries have every level of division, depending on their size. For example, Luxembourg and Cyprus only have local administrative units (LAUs); the three NUTS divisions each correspond to the entire country itself.

Former EU member-state
The United Kingdom left the European Union on 31 January 2020, the only member-state to ever do so.

Establishment
NUTS regions are generally based on existing national administrative subdivisions. In countries where only one or two regional subdivisions exist, or where the population of existing subdivisions is too small or too large, a second and/or third level is created. This may be on the first level (ex. France, Italy, Greece, and Spain), on the second (ex. Germany) and/or third level (ex. Belgium). In countries with small populations, where the entire country would be placed on the NUTS 2 or even NUTS 3 level (ex. Luxembourg, Cyprus), the regions at levels 1, 2 and 3 are identical to each other (and also to the entire country), but are coded with the appropriate length codes levels 1, 2 and 3.

The NUTS system favors existing administrative units, with one or more assigned to each NUTS level. Specific guidelines are based in population, leaving little or no role for other types of variables such as area, distance, topography, levels of jurisdiction or history, which can only be considered in (unspecified) types of special cases. From the NUTS Regulation, the average population size of the regions in the respective level shall lie within the following thresholds:

For non-administrative units, deviations from these population marks exist for particular geographical, socio-economic, historical, cultural or environmental circumstances, especially for islands and outermost regions.

Examples

 * IT: Italy
 * ITC: Northwest Italy
 * ITC1: Piedmont
 * ITC11: Metropolitan City of Turin


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2004 in aviation

This is a list of aviation-related events from 2004.

January

 * 2 January – Several British Airways flights from London Heathrow Airport to Washington, D.C., and Riyadh, Saudi Arabia are cancelled due to security fears.
 * 3 January – Flash Airlines Flight 604, a chartered Boeing 737-3Q8, crashes into the Red Sea off the coast of Egypt, killing all 148 aboard.
 * 13 January – Uzbekistan Airways Flight 1154, an Yakovlev Yak-40 crashes in Uzbekistan's capital of Tashkent, killing all 37 aboard.

February

 * Thai AirAsia begins flight operations, offering domestic airline service in Thailand.
 * The Spanish airline Vueling is founded. It will begin flight operations in July.
 * The Belgium-based airline BelgiumExel is founded and begins flight operations.
 * 10 February – Kish Air Flight 7170, the Fokker 50 EP-LCA, crashes into the ground while on final approach to a landing at Sharjah International Airport in Sharjah in the United Arab Emirates, killing 43 of the 46 people on board and injuring all three survivors.
 * 12 February – United Airlines creates a new airline, Ted, to serve as a divisional brand of United serving the low-cost vacation market.
 * 19 February – The Evergreen 747 Supertanker makes its first flight. Based on the Boeing 747-200 cargo aircraft and capable of carrying 19,600 U.S. gallons (16,320 Imperial gallons; 74,194 liters) of water, it is the world's largest aerial firefighting aircraft.
 * 23 February – The US Army cancels the Boeing-Sikorsky RAH-66 Comanche attack helicopter program. It had been planned to purchase as many as 650 Comanches, but it was argued that cancellation would free up funds for more urgent army aviation priorities. A total of $6.9 billion had already been spent on the RAH-66.
 * 26 February – President of Macedonia Boris Trajkovski and all eight other people on board are killed when a Macedonian government Beechcraft Super King Air 200 (registration Z3-BAB) crashes into a mountainside in Herzegovina near the villages of Huskovici and Rotimlja while on approach in thick fog and heavy rain to Mostar Airport in Mostar, Bosnia and Herzegovina.
 * 29 February – Canadian artist Toni Onley is killed when the Lake LA-4-200 Buccaneer amphibian he is piloting crashes into the Fraser River near Maple Ridge, British Columbia, Canada, while he is practicing takeoffs and landings. The plane sinks in 10 m of water.

March

 * 27 March – NASA's X-43 pilotless plane breaks world speed record for an atmospheric engine by briefly flying at 7700 km per hour (seven times the speed of sound)
 * 31 March – Mexicana leaves the Star Alliance.

April

 * 4 April – Alaska Airlines discontinues service between San Francisco and Tucson.
 * 14 April – Rico Linhas Aéreas Flight 4815, an Embraer EMB 120ER Brasilia, crashes on approach to a landing at Manaus, Brazil, killing all 33 people on board.
 * 18 April – Indian film star Soundarya and all three other people on board are killed when their Cessna 180 crashes in a field and burns just after takeoff from Jakkur Airfield in Bangalor, India.
 * 26 April – Alaska Airlines begins service between Seattle and Chicago-O'Hare.
 * 30 April – Aerobatic pilot Ian Groom is killed when his Sukhoi Su-31 crashes into the Atlantic Ocean while he is practicing spins off Fort Lauderdale, Florida, in preparation for the Air & Sea Show.

May

 * US Airways joins the Star Alliance.
 * Bucharest Otopeni International Airport in Bucharest, Romania, is renamed Bucharest Henri Coandă International Airport.
 * 1 May – The British airline Duo Airways (formerly Maersk Air UK) ceases operations, with at least four of its seven aircraft impounded at Birmingham Airport.
 * 5 May – Air France and Netherlands-based KLM (Royal Dutch Airlines) merge to form the new airline Air France–KLM.
 * 9 May
 * Southwest Airlines begins service to Philadelphia International Airport in Philadelphia, Pennsylvania.
 * American Eagle Flight 5401, an ATR 72, crashes on landing at Luis Muñoz Marín International Airport in San Juan, Puerto Rico, injuring 17 of the 26 people on board.
 * 12 May
 * The last F-4 Phantom II fighters are withdrawn from Israeli Air Force service.
 * Irish airline JetGreen Airways, which had only begun operations with a single Boeing 757 wet leased from Icelandair on 4 May, ceases operations.
 * 23 May – Frontier Airlines begins service to Philadelphia, Pennsylvania; Billings, Montana; and Spokane, Washington.
 * 25 May – Australian low cost airline Jetstar Airways begins operations.
 * 27 May – Delta Air Lines begins service between Cincinnati, Ohio, and New Haven, Connecticut.

June

 * 1 June
 * Air Baltic launches service from Vilnius, Lithuania, initially to five destinations.
 * America West Airlines starts service between Phoenix and Anchorage.
 * 6 June – Alaska Airlines starts service between Denver and Anchorage and discontinues service between San Jose and Tucson.
 * 16 June – Atlantic Coast Airlines begins service as a low-cost carrier under the new name Independence Air.
 * 18 June – The first missile strike by an American unmanned aerial vehicle inside Pakistan takes place when an AGM-114 Hellfire fired by an MQ-1 Predator strikes the house of local Taliban commander Nek Muhammad Wazir in Kari Kot, South Waziristan, killing him, his two brothers, and two bodyguards.
 * 20 June – Frontier Airlines begins service to Nashville, Tennessee.
 * 21 June – SpaceShipOne is the first non-government-built spacecraft to transport a person into space and return safely to earth.
 * 26 June – Belavia inaugurates service between Belarus and Hanover, Germany.
 * 29 June – Aboard Northwest Airlines Flight 327, a Boeing 757-200 bound from Detroit Metropolitan Wayne County Airport in Romulus, Michigan, to Los Angeles International Airport in Los Angeles, California, journalist Annie Jacobsen, a writer for WomensWallStreet, and her family report to air marshals that 14 Syrian men – musicians traveling to a performance – aboard the airliner are acting suspiciously and may be performing a "dry run" for a future terrorist attack. The air marshals disagree, and the Jacobsen family becomes so agitated and vocal that the air marshals begin to suspect them of trying to draw out the air marshals so that terrorists can target the marshals. Jacobsen later writes about the incident, bringing it to national attention in the United States.

July

 * 1 July
 * The Spanish airline Vueling begins flight operations.
 * Cape Air begins flights in the Mariana Islands. It operates under the Continental Connection brand.
 * 13 July – Air Moldova becomes a member of the International Air Transport Association.
 * 14–20 July – The 14th FAI World Rally Flying Championship takes place in Herning, Denmark. Individual winners: 1. Jiří Filip & Michal Filip (Czech), 2. František Cihlář & Milos Fiala (Czech), 3. Krzysztof Wieczorek & Krzysztof Skrętowicz (Poland); team winners: 1. Czech Republic, 2. Poland, 3. France.
 * 19–24 July – The 16th FAI World Precision Flying Championship takes place in Herning, Denmark. Individual winners: Krzysztof Wieczorek (Poland) – 3Xtrim, 2. Petr Opat (Czech) – Cessna 152, 3. Wacław Wieczorek (Poland) – PZL Wilga 2000; team winners: 1. Poland, 2. Czech Republic, 3. France.
 * 23 July – Air Ukraine's air operator's certificate is revoked. The airline had not operated since declaring bankruptcy in December 2002.

August

 * 4 August – Independence Air's status as a United Express carrier comes to an end.
 * 9 August – Several member states of the Pacific Islands Forum sign the Pacific Islands Civil Aviation Safety and Security Treaty in Apia, Samoa. The treaty will enter into force on 11 June 2005. It formally confirms the Pacific Aviation Safety Office, which had been formed informally in 2002.
 * 13 August – Air Tahoma Flight 185, a Convair 580 on a cargo flight, runs out of fuel due to pilot error and crashes short of the runway on final approach to Cincinnati/Northern Kentucky International Airport in Hebron, Kentucky, killing one of its two crew members.
 * 24 August – After departing Domodedovo International Airport in Moscow, Volga-AviaExpress Flight 1303, a Tupolev Tu-134 (NATO reporting name "Crusty"), explodes over Russia's Tula Oblast and crashes, killing all 43 people on board. Minutes later, Siberia Airlines Flight 1047, a Tupolev Tu-154 (NATO reporting name "Careless") which also had departed Domodedovo International, explodes over Russia's Rostov Oblast and crashes, killing all 46 people on board. The Russian government declares the explosions to have been caused by female Chechen suicide bombers.

September

 * KLM Cargo joins the Skyteam Cargo airline alliance.
 * 7 September – Indonesian human-rights and anti-corruption activist Munir Said Thalib dies of arsenic poisoning on a Garuda Indonesia flight from Jakarta, Indonesia, to Amsterdam in the Netherlands. The victim of an assassination, he apparently had been poisoned during a stopover in Singapore.
 * 11 September – Patriarch Peter VII of Alexandria and all 16 other people on board are killed in the crash of a Boeing CH-47D Chinook helicopter into the Aegean Sea off Mount Athos, Greece, 5.5 nautical miles (6.3 mi off the Chalkidiki Peninsula.
 * 13 September – Continental Airlines, Northwest Airlines, and KLM join the Skyteam airline alliance. It is the largest expansion of an airline alliance in history and makes Skyteam the second-largest alliance, moving it ahead of Oneworld. With the expansion, Skyteam serves more than 341 million customers, with 14,320 daily flights to 658 destinations in 130 countries.

October

 * Air Baltic is rebranded as airBaltic.
 * 1 October – American multi-sport athlete and former All-American Girls Professional Baseball League player Gertrude Dunn is killed when the Piper PA-28-180 Archer she is piloting crashes due to engine failure on takeoff from New Garden Airport in Avondale, Pennsylvania.
 * 3 October – Iraqi Airways makes an international flight for the first time since the Gulf War broke out in January 1991, flying from Baghdad, Iraq, to Amman, Jordan.
 * 4 October – SpaceShipOne successfully makes its third flight into space. It wins the Ansari X-Prize for proving to be a plausible option for space tourism.
 * 14 October
 * MK Airlines Flight 1602, a Boeing 747-200F cargo aircraft, strikes the ground and crashes immediately after takeoff from Halifax Stanfield International Airport in Enfield, Nova Scotia, Canada, killing its entire crew of seven.
 * During a ferry flight with no one else aboard, the pilot and copilot of Pinnacle Airlines Flight 3701, a Bombardier CRJ-200, decide to test the performance limits of the aircraft by pushing it to its maximum approved altitude of 41,000 ft. They conduct various non-standard maneuvers and reach the altitude, but overstress the engines, flame out, and stall. They recover from the stall at 38,000 ft and enter a glide. Never able to restart the engines and unable to glide far enough to reach any of six airfields they are advised to divert to, they eventually crash near Jefferson City, Missouri. Both pilots die in the crash.
 * 19 October – Corporate Airlines Flight 5966, a British Aerospace Jetstream 32, crashes on approach to Kirksville Regional Airport in Adair County, Missouri, near Kirksville, killing 13 of the 15 people on board and injuring both survivors.
 * 24 October – Flying in heavy fog, a Beechcraft Super King Air 200 owned by Hendrick Motorsports crashes into Bull Mountain, 7 mi from Blue Ridge Airport in Martinsville, Virginia, killing all 10 people on board. Former NASCAR Busch Series driver and owner Ricky Hendrick and Hendrick Motorsports Director of Engine Operations and lead engine builder Randy Dorton are among the dead.
 * 28 October – Boeing ceases production of the Boeing 757 airliner after manufacturing 1,050 of the aircraft for 54 customers.
 * 29 October – the Government of Benin establishes the Agence Nationale de l'Aviation Civile du Bénin ("Benin National Civil Aviation Agency") as Benin's national civil aviation authority. It replaces the  Direction de l’Aviation Civil ("Directorate of Civil Aviation").

November

 * 1 November – The second revival of Pan American Airways – nicknamed "Pan Am III" by some people – which had begun service in October 1999, ceases operations and turns its operations over to Boston-Maine Airways.
 * 2 November – Independence Air's status as a Delta Connection carrier comes to an end.
 * 3 November – Blue1 joins the Star Alliance as its first regional member.
 * 16 November – The National Aeronautics and Space Administration's X-43 reaches a record speed of Mach 9.8 (7,546 mph.
 * 18 November – Adria Airways and Croatia Airlines join the Star Alliance.
 * 21 November – China Eastern Airlines Flight 5210, a Bombardier CRJ-200LR, crashes into a park just after takeoff from Baotou Erliban Airport in Baotou, China, killing all 53 people on the aircraft and two people on the ground. An investigation finds that icing caused the crash.
 * 30 November – Lion Air Flight 583, a McDonnell Douglas MD-82 with 156 people on board, overruns the runway on landing in a hard rain at Adi Sumarmo Airport in Surakarta, Indonesia, and crashes, killing 25 people and injuring all 138 survivors.

December

 * The Indonesian airline Awair, which had suspended its operations in March 2002, resumes flights, now as an associate of AirAsia.
 * 9 December
 * United Airlines becomes the first American airline to land in Ho Chi Minh City, Vietnam, since Operation Frequent Wind during the fall of Saigon in April 1975.
 * The United States Army issues a request for proposals for the Armed Reconnaissance Helicopter (ARH). Ultimately, this will lead to the development of the Bell ARH-70 Arapaho.
 * 10 December
 * Two CT-114 Tutors from Canada's Snowbirds aerobatic team collide while training near Mossbank, Saskatchewan. Captain Miles Selby is killed and Captain Chuck Mallet is injured.
 * The United States Federal Aviation Administration issues an Emergency Airworthiness Directive effectively grounding the entire U.S. fleet of Beechcraft T-34 Mentor aircraft. The directive is in response to fatal in-flight structural failure accidents during simulated aerial combat flights.

First flights

 * Aero-Cam Slick 360

February

 * 19 February – Evergreen 747 Supertanker

March

 * 5 March – Virgin Atlantic GlobalFlyer
 * 12 March – Embraer 190

May

 * 29 May – Aceair AERIKS 200
 * 29 May – NAL Saras

June

 * 18 June – Airblue flies its first flight, a private airline in Pakistan
 * 21 June – First sub-orbital flight of SpaceShipOne

July

 * 8 July – HESA Saeqeh
 * 15 July – Aermacchi M-346
 * 20 July – Aerocomp Comp Air Jet

August

 * 26 August – BAE Systems Nimrod MRA4

October

 * 16 October – Quest Kodiak

December

 * 17 December – Antonov An-148
 * 18 December – Bell 210
 * 31 December – Eclipse 500

Entered service

 * AgustaWestland Apache with the British Army

Deadliest crash
The deadliest crash of this year was Flash Airlines Flight 604, a Boeing 737 which crashed into the Red Sea near Sharm El Sheikh, Egypt on 3 January, killing all 148 people on board.

title: 2004 in aviation