Whey doesn't jets have ac?

Answer 1

grumpy has it pretty close.

Bleed air from the jet engines is used to pressurize the cabin and also provide a comfortable environment for passengers. The bleed air comes after it has been compressed by the compressor stage of the engine, and as air is compressed it is heated. Once air is bled from the compressor it will be several hundred degrees F and will need to be cooled down. There are a couple of ways to do this. Some aircraft have systems similar to that in a car, where a vapor system (often Freon) is used to cool down the air.

More common on large aircraft is a system that takes the heated compressed air and decompresses, or expands, the air which will cool it down. This cooled air is then pumped into the cabin and is constantly circulated to keep the cabin from feeling stuffy. The pilot can control the cabin altitude (the height that it feels like in the plane) and based on the setting, valves will regulate how quickly and how much air is circulated. Most airlines will cruise at a cabin altitude of around 8000 ft no matter what altitude they are flying at as long as it is above 8000 ft. Aircraft aren't designed to have a larger pressure outside the aircraft than inside, so if the cabin altitude is set higher than actual altitude, major structural damage can occur to the aircraft.

This process will both pressurize the cabin and provide a comfortable environment for passengers.

Answer 2

What exactly are you asking? Are you asking about air conditioning or are you asking about electricity (Alternate Current or AC?)
All aircraft (especially the larger commercial jets) have air conditioning, it operates, just like the one you have at home (or your local mall) except the aircraft uses engine bleed (whether directly from the engines or the APU). Many airports on the ground now stick in an exterior air cooling system, so the APU can be shut down (for long periods of not flying) Saving fuel, lowering noise & also helpful to the enviroment.
If you are actually talking about AC (alternating current) the the answer is yes, aircraft do have AC just a different voltage/amperage to what is used for homes, businesses around the world, because for the amount of gizmos & gadets that have to be powered in flight (not only for flying safely,but also for passenger comfort) it requires a huge amount of amperage, (& unfortunately a ground power station is just to big to fit into an aircraft), so they use something that can be lightweight, economical, and that produces more than enough electricity to do the taks at hand.

Answer 3

Many commercial aircraft do. The cabins have the ability to be heated or cooled depending on the situation. The AC is powered by the APU (auxiliary power unit) which is basically the planes extra engine that powers the electricity of the aircraft.

Answer 4

jets do have ac but unlike Freon systems on the ground they use bleed air off the engine to power a cooling turbine. the cold air form the cooling turbine is mixed with hot bleed air off the engine to deliver the desired temperature to the cabin. this is high volume air and is used to pressurize the aircraft as well. these systems are automated so the pilot just dials in the desired temperature. Don't worry they have many safety features so you don't get to hot or cold.

Answer 5

Large commercial aircraft use what is called a boot-strap system to produce AC on the ground. The boot –trap system uses two compressor wheel one to compress the air and the other to slow it down or expand it. When air expands it super cools. A French chap developed idea. So bleed air is taken form the engine compression stage and piped to the air-condition packs to turn the boot-strap system to produce cool air. The is a pretty simple system and saves weight on aircraft.

Answer 6

All answers so far explain how the air conditioning works, but not why. Yes, Airlines do air condition, but jet fighters don't. As explained, you rob air off the engine which also robs power. Fighters need the thrust more than air conditioning for performance.

Answer 7

The Trinidad TB20 I used to have, had AC on it. Living in So Cal at the time, it was a much-appreciated feature on those 110 degree summer days.

Answer 8

Most do !!

Heck, even my old helicopter (SH-60B Seahawk) had a form of air-conditioning... albeit mostly for the electronics !! Bleed air off the APU or Engine decompressed (therefore chilled)... GAWD it was nice on HOT days near the equator, around San Diego, or in the Persian Gulf

Answer 9

Jets must have air conditioning if they are to be pressurized. They use bleed air from the compressor section of the engine to pressurize the aircraft. The temperature of that air is several hundred degrees. If it were not cooled through the air conditioning packs, the passengers would be pretty much roasted alive.

Answer 10

there would be no ponit at the altitude a jet flies the air outside is about 10 to 20 degrees below 0.