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>Over 100 successful ejections per year? That's wild! That sounds like an awful lot of hull losses. I remember calculating a few years ago that more than 10% o

>Over 100 successful ejections per year? That's wild! That sounds like an awful lot of hull losses. I remember calculating a few years ago that more than 10% of the ejector seats sold by Martin-Baker have been used to eject. Military aircraft operations, even in peacetime, are much more dangerous than the vast majority of civilian fixed-wing flight (except airshows/racing and maybe cropdusting). I don't know how much of that difference is the flight profile being inherently more dangerous (closer to terrain), and how much is it being harder on the aircraft.

throwup238 2y ago
They're more dangerous mostly because they're optimized for maneuverability which requires trading off aerodynamic stability and glide ratio. All aircraft have problems mid-flight and most pilot training is about how to deal with that but when something goes wrong, fighter jets just don't have much time to recover before they plummet. That maneuverability also makes it a lot easier to get disoriented and lose control. Trainer jets like the L39 albatross have a less maneuverable design in exchange for being a lot more survivable in event of a problem. The engines themselves aren't that much less reliable - some engines like the Garrett TFE731 have a TBO of 4,000 hours which is significantly more than many GA engines like the Continental in an entry level Cessna.
- shiroiushi 2y ago
  >some engines like the Garrett TFE731 have a TBO of 4,000 hours which is significantly more than many GA engines like the Continental in an entry level Cessna. That shouldn't be a big surprise: jet engines are turbines with basically only one moving part that just spins, whereas those crappy GA engines are reciprocating piston engines with designs that haven't changed since the 1950s.
  - tialaramex 2y ago
    This incredible reliability is the justification for TOPS and ETOPS policy in which suitably qualified aeroplanes with only two jet engines are allowed to fly over an ocean. Before TOPS this is why you see jet aeroplanes with three engines, they don't need three engines to fly, but the regulations required that if two engines fail the plane must get to safety, with TOPS that's no longer required (hence the joke expansion for ETOPS: Engines Turn Or Passengers Swim) and so new planes with three engines didn't make sense. With piston engines two engines failing is a completely reasonable thing which will sometimes happen to say, a transatlantic flight. In the early days of such travel, the demands are such that all the practical aeroplanes are four engine models anyway, so limping to an abort airfield on two engines was a reasonable strategy if two failed, but once jet engines on passenger planes were a thing, their enormous reliability makes this unnecessary hence TOPS and then ETOPS.
    - tialaramex 2y ago
      The mentions of TOPS above are a brain misfire. ETOPS was altered repeatedly but it was always named ETOPS, at first allowing 90 minutes, then 120 minutes and eventually 180 minutes of assumed single engine range. A modern twin engine jet can go a long way in 180 minutes at design single engine performance.

throwup238 2y ago

They're more dangerous mostly because they're optimized for maneuverability which requires trading off aerodynamic stability and glide ratio. All aircraft have problems mid-flight and most pilot training is about how to deal with that but when something goes wrong, fighter jets just don't have much time to recover before they plummet. That maneuverability also makes it a lot easier to get disoriented and lose control. Trainer jets like the L39 albatross have a less maneuverable design in exchange for being a lot more survivable in event of a problem. The engines themselves aren't that much less reliable - some engines like the Garrett TFE731 have a TBO of 4,000 hours which is significantly more than many GA engines like the Continental in an entry level Cessna.

shiroiushi 2y ago
>some engines like the Garrett TFE731 have a TBO of 4,000 hours which is significantly more than many GA engines like the Continental in an entry level Cessna. That shouldn't be a big surprise: jet engines are turbines with basically only one moving part that just spins, whereas those crappy GA engines are reciprocating piston engines with designs that haven't changed since the 1950s.
- tialaramex 2y ago
  This incredible reliability is the justification for TOPS and ETOPS policy in which suitably qualified aeroplanes with only two jet engines are allowed to fly over an ocean. Before TOPS this is why you see jet aeroplanes with three engines, they don't need three engines to fly, but the regulations required that if two engines fail the plane must get to safety, with TOPS that's no longer required (hence the joke expansion for ETOPS: Engines Turn Or Passengers Swim) and so new planes with three engines didn't make sense. With piston engines two engines failing is a completely reasonable thing which will sometimes happen to say, a transatlantic flight. In the early days of such travel, the demands are such that all the practical aeroplanes are four engine models anyway, so limping to an abort airfield on two engines was a reasonable strategy if two failed, but once jet engines on passenger planes were a thing, their enormous reliability makes this unnecessary hence TOPS and then ETOPS.
  - tialaramex 2y ago
    The mentions of TOPS above are a brain misfire. ETOPS was altered repeatedly but it was always named ETOPS, at first allowing 90 minutes, then 120 minutes and eventually 180 minutes of assumed single engine range. A modern twin engine jet can go a long way in 180 minutes at design single engine performance.