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0 pointsHallucinaut4y ago0 comments

Obviously if you're ejecting at or near supersonic speeds there are other stresses, but if the trauma is mainly from the ejection booster itself why is it still done with such force?

It seems like a majority of ejections shouldn't be benefited by half a second less time to achieve clearance (or the jet itself could detect altitude and adjust the speed to increase survivability).

I'm guessing this is also a function of trying to achieve lateral separation from the ensuing fireball in a crash but it surprises me rates are so high for injury.

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TylerE4y ago

Because you have to get up and over the tail of the airplane without it slicing you like a cleaver.

londons_explore4y ago

A cleverer ejection seat could track the tail and body of the craft, and adjust the rocket force based on the trajectories in each case.

Then you don't have to use enough force to avoid the tail in every case, but merely enough force to avoid the tail in this case, which will normally be far less.

sokoloff4y ago

The aircraft being exited is often not in a factory nominal condition.

TylerE4y ago

Solid fuel rocket, so no throttle.

krisoft4y ago

Yes. And if someone is curious why are we using solid fueled rockets in this application:

The big benefit of solid fueled rockets is that they are very reliable, and require no maintenance. They are basically a big “candle” composed of a mix of fuel and oxidizer. You can lit it a day after it was made or twenty years later it will work the same.

The liquid fueled options have valves and other moving parts which can jam, corrode and degrade with time. So it would require frequent maintenance and would still be likely less reliable than the solid fueled variety.

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HPsquared4y ago

You could use an array of motors, and only activate however many are needed.

samatman4y ago

While I'm unaware of an ejection seat which blows the tail off the aircraft backward with another shaped charge, there's nothing preventing this.

alanbernstein4y ago

Of course there is: whatever event warranted the ejection. The seat/canopy mechanism is relatively localized within the aircraft, adding one more system to fail is perhaps frowned upon in this absolute last-chance survival system.

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TylerE4y ago

Because you have to get up and over the tail of the airplane without it slicing you like a cleaver.

londons_explore4y ago

A cleverer ejection seat could track the tail and body of the craft, and adjust the rocket force based on the trajectories in each case.

Then you don't have to use enough force to avoid the tail in every case, but merely enough force to avoid the tail in this case, which will normally be far less.

sokoloff4y ago

The aircraft being exited is often not in a factory nominal condition.

TylerE4y ago

Solid fuel rocket, so no throttle.

krisoft4y ago

Yes. And if someone is curious why are we using solid fueled rockets in this application:

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HPsquared4y ago

You could use an array of motors, and only activate however many are needed.

samatman4y ago

While I'm unaware of an ejection seat which blows the tail off the aircraft backward with another shaped charge, there's nothing preventing this.

alanbernstein4y ago

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