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On aircraft with 2 crew placed one in front of each other (tandem) equipped with ejection seats, the rear seat is ejected before the front one (described here for the F-14).

  • Why is the rear seat ejected before the front one?
  • Is an aircraft without ejection seat (e.g. glider) evacuated in the same order and why?
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Manu H
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    Have you not seen Top Gun? It's so the front seat can hold the rear seat afloat till the rescue chopper arrives! – Jamiec Oct 26 '15 at 09:37
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    There is no sequence in a glider. Everyone tries to get out as best as he can, but there are very few cases. The few I have heard of involved an instructor in the back seat, and in one case the instructor pulled the student out before jumping himself. When facing forward it is simpler for the rear seater to pull out the forward seater than vice versa. – Peter Kämpf Oct 26 '15 at 11:47

4 Answers4

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If the front seat ejected first, the drag would probably bring him too close in the trajectory of the rear seat, thus making a collision of both probable.

Since the rear seat is ejected first, it experiences drag earlier than the front seat and will thus not have an increased probability of hitting it.

SentryRaven
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    Also flames from ejection rockets could possibly burn the second seat. – Peter M. - stands for Monica Oct 26 '15 at 17:38
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    Geeze, it isn't drag it is the plane's velocity, unless the plane is going backwards. So look at the sequence (1) front seat goes first, (2)then the plane goes forward, (3)then the second seat ejects. In such a sequence the second seat is ejecting "under" the first seat, thus the two could collide. Also If front seat goes first then the fume/fire from front seat ejection are swept over the second seat. – MaxW Oct 28 '15 at 00:21
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    @MaxW actually, an ejection seat configured to fire "straight up" will inherit the forward velocity of the plane, so the front seat will go up-and-forward, with a forward component exactly corresponding to the velocity of the plane. Thus, the front seat would be "right over head" when the second seat is fired. However, when you add wind resistence into the mix, the ejection seat will begin to drift backwards relative to the plane (which is far more aerodynamic). – Cort Ammon Oct 28 '15 at 01:10
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    I suppose you could tilt the ejection seat backwards a little to cancel out the forward velocity and fire straight up in a ground frame, but that'd be very speed specific, so it seems like an unlikely engineering solution. – Cort Ammon Oct 28 '15 at 01:11
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    @CortAmmon: I'm pretty sure you want all of your ejection-seat rocket's delta-V separating the pilot from the plane, so they don't get clipped by the vertical fin (or some other part of the plane if it's travelling at a crazy attitude in a spin). The acceleration is already high enough to be very stressful on the human body, so you can't just use bigger rockets. There's just no good reason not to let wind resistance do the work for you, once you get the pilot clear of the plane. – Peter Cordes Oct 28 '15 at 01:53
  • @MaxW: Read about "conservation of momentum". Without drag from air, the seats would continue travelling forwards at the plane's velocity. Unless the plane is actually accelerating, "then the plane goes forward" is nonsense. – Lightness Races in Orbit Oct 28 '15 at 10:21
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    @LightnessRacesinOrbit - except that air drag is present; quite a bit of it. The aircraft is much heavier and more aerodynamic than the pilot and ejection seat, and at ejection the aircraft's often still under power, so the force of drag slows the ejecting pilot relative to the aircraft, so the aircraft would move forward relative to the pilot (or the pilot would move rearward compared to the aircraft, either way). – KeithS Oct 28 '15 at 20:09
  • As far as trajectory of ejection, most fighters have what's called a "zero-zero" ejection seat; the seat is capable, using booster rockets, of getting the pilot high enough and far enough away from the aircraft that it can be used at zero altitude, zero forward airspeed and/or groundspeed. This allows it to be used during emergencies on the ground, such as a fuel leak and fire or an armed weapon detonating on the rail (both of which have happened). A zero-zero seat, used as such, actually launches the pilot forward because the rockets are placed toward the rear of the seat. – KeithS Oct 28 '15 at 20:15
  • Here's a simple video showing the difference between older explosive seats and newer zero-zero seats: https://www.youtube.com/watch?v=Z1cnvJO1TF8 At speed, the forward trajectory is still present, primarily to ensure the pilot gets enough distance from the aircraft to clear the tail before drag slows him. – KeithS Oct 28 '15 at 20:21
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    @KeithS: Yes, that's exactly my point. It's drag. Max was suggesting that drag had nothing to do with it, that somehow once the pilot had ejected the plane magically continued on without her. – Lightness Races in Orbit Oct 29 '15 at 00:02
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In general, in aircraft with tandem seating, the rear seat (having the Radar Officer) ejects first, followed by the forward (pilot) seat, after a delay of ~0.3 seconds. This is done for a few reasons:

  • If the pilot seat is ejected first (or both are ejected simultaneously), there is a possibility that the pilot seat may collide (as it will be dragged backwards due to wind force) with the copilot seat or damage the (rear) canopy during ejection.

  • In some aircraft, the pilot can eject only after the rear seat is ejected. This is so that, in case the rear seat fails to eject, the pilot can still control the aircraft and 'pop out' the Radar officer's seat by maneuvering. For example, the F-4 procedure called for the pilot to roll the aircraft inverted with a positive 'g' and then pop the radar officer with a negative 'g'.

In some cases like the (Mig-15 UTI), the rear seats were ejected first simply because the gas jets from the pilot seat ejection mechanism made ejecting from the rear compartment impossible.

aeroalias
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    and I'd not like to get a rocket blast from the front seat in my face if I were in the rear seat... – jwenting Oct 26 '15 at 11:34
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    @jwenting if you must evacuate the aircraft, wounds are only the second most important thing (the first one being stay alive). – Manu H Oct 26 '15 at 13:33
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    @ManuH having your face burned off by a rocket blast isn't conducive to staying alive... – jwenting Oct 26 '15 at 13:38
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    Neither is smashing head first into another ejection seat's bottom. – Nelson Oct 28 '15 at 09:07
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I'd think the main reason would be to avoid cooking the rear seat crew while the rockets were firing as well as to avoid an accidental collision between the front seat and the rear seat crew. After all - the jet is likely to be travelling forward at a relatively high velocity when the two are coming out of the plane (or what's left of it).

kbcmdba
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The pilot ejects last so that he/she can attempt to remain in control of the aircraft.

Rico
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    Do you have some source or reference for this? I'm not saying you're wrong, but it's always good to provide as many details as possible. – Pondlife Oct 27 '15 at 13:16
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    I'm pretty sure that if the pilot wanted to remain in control of the aircraft, he wouldn't eject at all, and, conversely, he would only eject if he had already lost control of the aircraft, or he knew that such loss of control is imminent and certain. – Jörg W Mittag Oct 27 '15 at 16:13
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    This is supported by the story in this answer to a related question. – fooot Oct 27 '15 at 17:04
  • Again no sources, but more anecdotes. He might eject the rear seat in attempt to minimize risk to human life while he does a difficult landing (I vaguely remember something with parachutists that jumped out of a malfunction plane, while the pilot landed safely later). Also possible: To keep the plane under control for a few more seconds before he eject, instead of screwing over the rear seat. – Dorus Oct 27 '15 at 21:06
  • @Dorus - Every aircraft ejection system I know of triggers every ejection seat in the aircraft when one handle is pulled; you can't selectively eject your copilot/GIB and stay in the plane. In larger aircraft like the B-1B and B-52, not all crewmen are in an ejection seat, so the flight crew may delay ejection as long as possible until those crewmen can bail out another way, but when he pulls the handle, barring a malfunction, everyone in a rocket seat is gone. – KeithS Oct 28 '15 at 20:25
  • As far as the pilot ejecting last to stay in control, the time difference between the rear seat and front seat ejection is less than a second. A lot can happen, but if the decision has been made to eject, "control" is not under consideration. – KeithS Oct 28 '15 at 20:30
  • If the pilot pulls his handle it will always initiate a command eject sequence. Non-pilot crew members may eject themselves without anyone else being ejected, and in some aircraft a non-pilot crewmember may also be able to select a command eject sequence. However, there is no way for a pilot or anyone else to selectively eject someone else while they remain in the aircraft. – Michael Hall Apr 26 '19 at 18:58
  • ADDENDUM: The above is based on my personal experience in the 4 seat EA-6B, but I would challenge anyone to find an exception to my statements. – Michael Hall Apr 26 '19 at 19:05
  • The F-14 had an EJECT CMD selector on the pilot’s Landing Gear Panel, below EMERG STORES jettison and the NOSE STRUT switch. In the usual MCO mode, either crew member could command ejection of both, RIO first. In PILOT mode, the pilot still ejects both and goes second;?the RIO only ejects himself. – Bob Jacobsen Mar 13 '20 at 04:52