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  #1  
Old 05-05-2003, 04:39 AM
Ranchoth Ranchoth is offline
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If it's OK otherwise, is an F-16 still flyable after an Ejection Seat firing?

I'll try and fill out my "weird post" quota for the week now...Say there's a Jet Fighter (An F-16, for example) flying at cruising speed and altitude. All systems and equipment functioning fine. Now, for some reason, the pilot ejects...

If you could, magically, have someone appear in the cockpit right after the ejection (Superman?), would the aircraft still be flyable (Aside from the slight problem of having an open canopy at 400 knots. Not to mention no seat), or would the ejection seat's firing have destroyed the flight controls, or even damaged or destroyed any other systems on board?


And no, I'm not planning on trying this out for myself. Even though, for obvious reasons, it's so very tempting.



Ranchoth
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  #2  
Old 05-05-2003, 05:52 AM
Nanoda Nanoda is offline
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Did something end up in your yard you should tell someone about?

Well, I won't make you. My WAG is that it would be flyable. Certainly the aircraft continue to fly after you've left the vicinity (as some people relate here)along with the seat, not much appear to be jettisoned, save for the ends of the quick-disconnects for radio, air, suit plugs, etc. I doubt even the initial explosive charge could seriously damage the interior of the cockpit. As is mentioned elsewhere near that first link, most seats withdraw the pilots arms and legs, lest they strike something in the cockpit, so you're probably alright on that angle too.

Anyhow, let us know how that works for you.
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  #3  
Old 05-05-2003, 09:38 AM
NurseCarmen NurseCarmen is offline
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Keith Gallagher is one flyboy who is very happy his pilot could keep flying.
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  #4  
Old 05-05-2003, 09:45 AM
El Marko El Marko is offline
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Following the detonation of explosive charges to release the canopy, the ejection seat is propelled out of the cockpit by a rocket engine (a small one, but still...). Anyway, all that fire/heat etc... is probably enough to destroy most of your instruments, especially if it's one of those new-fangled "glass cockpits" with LCD screens instead of fixed instrument clusters. Any other plastics in the immediate area have probably melted at that point too.

As an aside and purely for anecdotal fun, there was a recent episode of JAG where two of the main characters were flying an F-14 Tomcat. The back-seater accidentally ejected, leaving the front-seater (i.e. the pilot) behind. The pilot was able to land the plane somehow, but I'd have to chalk up the entire scenario to TV silliness. It doesn't strike me as a very safe system to allow one seat to eject while leaving the other behind for the aforementioned seat rocket motor to fricassee.
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  #5  
Old 05-05-2003, 11:27 AM
Bookkeeper Bookkeeper is offline
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The initial ejection impulse is usually provided by a cartridge (sort of a giant blank), and the rocket motor doesn't kick in until partway through the ejection sequence. There would be little or no damage to the cockpit from the ejection, as the rocket blast happens mostly or completely after the seat has left the cockpit and acts to move it safely clear of the fin and other aircraft "stick-out" bits.

With reference to the F-14 ejection mentioned by El Marko, it is usual in two-seat or multi-seat aircraft for the pilot to stay and maintain control of the aircraft when possible until everyone else has ejected before ejecting him/herself. This prevents the aircraft from getting into uncontrolled manuevers which might prevent safe ejection and also allows him/her to confirm that everyone else has ejected. (Sort of an Air Force equivalent of the navy tradition of the captain being the last one off a sinking ship.)

There are not a lot of different models of ejection seats - not a lot of manufacturers and air forces also try to standardize these as much as possible for ease of procurement/maintenance and simplicity of use. There are differences between models, but generally they work on the same principles.
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  #6  
Old 05-05-2003, 12:37 PM
SmackFu SmackFu is offline
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You don't even have to invoke magic here... just set it off when the plane is standing still on the ground.
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  #7  
Old 05-05-2003, 02:05 PM
Padeye Padeye is offline
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The seats are only part of the problem. The canopy has to be extremely durable and well bolted down to keep it from flying off like a baseball cap at mach 2. The F-14 has hooks that the canopy locks into down both sides of the cockpit. When it is time to eject there isn't time to get the canopy off the normal way so the hooks are conneted by shielded mild detonating cord that blows them apart in a few milliseconds. The canopy is then jettisoned by a gas piston that throws the 300lb assembly clear of the airplane, destroying the hinge mechanism in the process.

Bottom line is you only eject or jettison a canopy in dire circumstancs that mean loss of the airplane. If by chance the plane isn't destroyed and the factory is able to rebuild the mangled cockpit and canopy sills that's just gravy.

The pilot in an F-14 has a selector for pilot or MCO control of the front ejection seat. With the swith in MCO position the RIO in the back seat will cause both seats to eject (back seat first of course). This is normally done on landings because the pilot is pretty busy while the back seater has his/her hand on or near the ejection handle. I know one F-14 pilot who was saved becasue of this. With the selector in pilot position only the pilot can eject the front seat.
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  #8  
Old 05-05-2003, 02:08 PM
Padeye Padeye is offline
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Quote:
Originally posted by El Marko
It doesn't strike me as a very safe system to allow one seat to eject while leaving the other behind for the aforementioned seat rocket motor to fricassee.
In the F-14 only the back seat can eject by itself and it always goes first. The pilot in the front seat is in no danger from the rocket motor from the back seat as it's well behind and the pilot is shielded by his own seat. In any event the seat motor is not directed at instrumentation and is gone in a small fraction of second anyway, too fast to cause much damage.
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  #9  
Old 05-05-2003, 05:25 PM
Chronos Chronos is offline
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At the USAF museum in Dayton, they have a plane which (by pure luck) landed itself after the pilot had ejected. Apparently, for reasons the museum sign didn't go into, the plane had gone out of control, and the pilot ejected. But somehow, the loss of the canopy re-stabilized the plane, and it ended up landing gently in the middle of a cornfield.

After a few moments on Google, I have more information.
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  #10  
Old 05-06-2003, 08:54 AM
Kilt-wearin' man Kilt-wearin' man is offline
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Quote:
Originally posted by El Marko
As an aside and purely for anecdotal fun, there was a recent episode of JAG where two of the main characters were flying an F-14 Tomcat. The back-seater accidentally ejected, leaving the front-seater (i.e. the pilot) behind. The pilot was able to land the plane somehow, but I'd have to chalk up the entire scenario to TV silliness. It doesn't strike me as a very safe system to allow one seat to eject while leaving the other behind for the aforementioned seat rocket motor to fricassee.
I refer you to the link in Nurse Carmen's post that appears immediately before yours. I've seen several photographs of F-14 and T-38 "convertible" models - single ejections in two-seat aircraft leaving one crewman and no canopy to land the plane. The ejection system isn't as destructive as you might think - after all, it only has to lob a few hundred pounds worth of pilot and seat out of the cockpit - hopefully without injuring said pilot.
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  #11  
Old 05-09-2003, 06:04 PM
El Marko El Marko is offline
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I stand corrected and humbly withdraw my previous comments.
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