# Are fighter jet cabins pressurized?

I heard once that fighter jet cabins are NOT pressurized, but the pilot's suit is, which prevents problems with decompression if the cabin gets shot.

But a military fighter pilot much later told me that the cabin is, in fact, pressurized and that getting shot (the cabin) and the resulting decompression are not that much of a bother, at all.

• This answer mentions that they are pressurized, but not as much as a passenger jet.
– fooot
Dec 8 '14 at 18:41
• Historical perspective: Many German fighters of WW II had pressurized cockpits. For example, the models of the Me-109 G ending on an even number had a pressurized cockpit, while the odd-numbered ones had an unpressurized cockpit. Feb 19 '16 at 15:15
• Yes to cool the electronics. Jun 14 '16 at 14:06

Cabins of fighter jets are in fact pressurized, but not same as the passenger airplanes. Cabin pressure in a passenger airplane will increase (almost in a linear fashion) as the airplane climbs. However, fighters keep ambient air pressure to a certain altitude. It maintains this pressure until a certain pressure differential is met, and then cabin altitude increases to maintain this differential.

Therefore at higher altitudes, cabin pressure in a fighter jet is low enough that supplemental oxygen is required for the pilot(s). This is supplied via On-Board Oxygen Generation Systems.

By not pressurizing the cabin completely reduces stress on air frame and is beneficial during an unplanned decompression.

By the way, your friend (military fighter pilot) is correct.

• "Cabin pressure in a passenger airplane will increase (almost in a linear fashion) as the airplane climbs." Surely you meant to say something else. The cabin pressure at cruise altitude is considerably lower than it was a second after the plane took off. Dec 8 '14 at 21:01
• I think you are confusing "cabin altitude" with "cabin pressure" here. Dec 8 '14 at 21:36
• Maybe he meant the pressure differential Feb 19 '16 at 14:48
• @Antzi: Is the F-16 cockpit pressurized? confirms that constant pressure difference is how fighter cabin-pressure systems do usually operate, above a certain altitude, agreeing with other answers on this question. So that's the right answer, and probably what the author of this answer was thinking but didn't actually type. (That linked question has good answers.) Jan 6 '20 at 22:01

# Typical Cabin Pressurization Schedule for a Fighter

The A7-E has an air-conditioning systems that maintains the cockpit environment at a specified temperature and pressure. The conditioned air enters the cockpit through a flow control valve and is distributed to vents around the canopy and window areas. The cabin pressure is maintained by a cockpit pressure regulator, which releases air into the nose cone of the aircraft to maintain the specified pressure as detailed in the graph shown below (A7E NATOPS Manual Section I - The Aircraft).

This pressurization schedule has the cockpit unpressurized from sea level to 8,000 feet. Above 8,000 feet, and up to 23,000 feet, the cockpit is kept at 8,000 feet. For any altitude above 23,000 feet a 5 psi differential is maintained between the cockpit pressure and the flight altitude pressure.

The cockpit altitude is displayed on a gauge on the forward console.

The cabin pressurization is regulated when the cabin pressurization switch is in the CABIN PRESS position, and will be dumped in the CABIN DUMP position. Essentially, all air to the air conditioning turbine is shut off. There is also an emergency vent air knob for ventilation, that can also be used to reduce cabin pressure.

Regulations required pilots to be on oxygen from start-up to shut-down.

# Managing Oxygen & Pressurization

I volunteered to go ashore in Greece to be a liaison between NATO forces there and the USS Nimitz. They were concerned about US aircraft entering Greece airspace to conduct their scheduled missions, while Turkish fighters were also violating the same airspace. I was to be ferried in an S3.

I was in the back seat in the TACCO (tactical officer) position on the right-hand side. We had taken the catapult shot and were climbing out. I was talking with the crew member across from me in the SENSO (sensor operator) seat when he asked me how I felt. "Dizzy," I said. He pinched a fingernail and told me he was going to checkout the pilot and copilot. He came back and said they had lost cabin pressurization, and that we needed to put on our oxygen masks. I had been flying for so many years with the oxygen mask always strapped to my face that I never paid attention to the signs of hypoxia. It always amazed me all the various ways one could get in trouble airborne.

Yes they are. There are two pressures available to aircrew of fighters. One is a combat pressure for minimizing decompression if the cockpit is hit. The second is for ferry flights where a more comfortable pressure is maintained to reduce crew fatigue.

Pressurisation is required in fighter pilot because as per altitude increase pressure reduces so it is required to maintain the cabin pressure relative to ambient pressure...

• welcome to aviation.se. I'm sorry, but I don't fully understand what you mean with as per altitude increase pressure reduces so it is required to maintain the cabin pressure relative to ambient pressure, could you please consider writing a more complete answer?
– Federico
Aug 8 '16 at 11:02