4 ms·

Instead of modifying the plane to support an unpressurized bomb bay in a pressurized plan could they not pressurize the plane at all, and provide the crew with

• ethbr1 1y ago
  Just so we're clear... the idea here is to take an aircraft: 1) whose structural characteristics were calculated with it pressurized at altitude, and instead fly it unpressurized 2) whose control surfaces were designed for a passenger/cargo load, and instead takeoff at max weight and land at minimum weight, with weight concentrated in bombs 3) with rocket assisted takeoff ? Sure. Sounds great. Will probably, mostly work.
  • tzs 1y ago
    Those structural characteristic calculations for flying pressurized are to calculate whether or not the structure can withstand the massive forces from the pressure differential between the pressurized volumes (cabin and cargo hold) and the outside atmosphere. If you were to fly it unpressurized there would be no such massive forces because there would be no pressure differential. The structural requirements would be the same as they are for when the plane flies unpressurized at low altitudes.
    • ethbr1 1y ago
      Wouldn't a pressurized cabin be more rigid than an unpressurized one? Since you're tensioning everything internally?
      • tzs 1y ago
        Probably. Airliners are pressurized to around 0.8 atm when at cruising altitude. The atmospheric pressure around 0.26 atm, so there is a pressure difference of around 0.54 atm. That will cause a considerable outward force on the cabin which would result in a lot of tension. If you didn't pressurize the cabin than the cabin would be at around 0.26 atm, which is the same as the outside air, and so there would not be that large outward force, and so much less tension. But the plane should be fine with that, because that's also the situation in the plane at low altitude.
• hollerith 1y ago
  Not pressurizing the plane at all is possible (the bombers of WW II were unpressurized for example until the B-29) but is probably not a good idea in light of the fact that even the F-35, where weight is very costly, has a pressurized cabin even though there is only ever one person in the cabin. They wouldn't have done that unless the need for pressurization was great: weight is very costly on the F-35. For example, they did a lot of research and development to design an intake with exactly the right shape to avoid the need for a variable intake ramp (and the actuators needed to vary the position ramp). For another example, they developed the software necessary for the plane to do "aerodynamic braking" to slow the plane down after touchdown, which eliminated the need for a parachute (which a lot of older fighters had) and reduced the need for wheel brakes (allowing the landing gear to be lighter). Reading more, the F-35 is designed to "operate above 50,000 ft, where outside pressure is near-vacuum" (quoting an LLM). The un-pressurized bombers of WW II couldn't operate at those altitudes (even though the crew wore heated clothing and breathed supplemental oxygen delivered through masks).
• nradov 1y ago
  You've got to be kidding. Crew performance goes to crap when wearing the pressure suits that would be needed for long missions at high altitude, like above FL250. It would never work.
  • tzs 1y ago
    It worked with B-17 and B-24 bombers in WW2, which flew at FL250 or higher and were unpressurized.