Ejection... Cutting it fine

[Marcantilan]

That was a case where navigators were really useful.

[BOAC]

Back on track.............

Did the double ejection cause the aircraft to pitch down?

- I suggest it far more likely that the 4 year old trainer was pulling back on the stick like no tomorrow to 'stretch that glide, man' and strange things happen when you let go to pull the handle. Not forgetting, of course, probably rocket seats.

Out of passing interest, my BoI calculated I had 1/2 second left when I pulled the handle. Thought I was a gonner, guv.

[ExAdvert]

"The RAF poster I saw at Valley said - Lucky, Dead Lucky, Dead

SGC"

I remember this poster... it was either "Eject in time" or "Abort in time" with 3 pictures of a Hawk getting progressively closer to a cloud-covered mountain. The first had the aircraft aborting nice & early, the second quite late & the third not at all. The captions were "Dead Easy", "Dead Lucky" & "Dead....." to which some smart*rse had added ".....Punchy"

Funny but......

Oddly enough the FSO didn't see the funny side.

[galaxy flyer]

I know how you feel, BOAC!. I got out of the flaming bundle of wreckage of an A-10 at about 400'. My margin was also measured in tenths of a second.

GF

[Agaricus bisporus]

Any word on what happened to he helicopter?

4 crashes for one airshow...is there something the Venezuelans are't doing right?

[SOSL]

Dead Pan #13

It has been done. Wyton, Canberra, Primary school - and many others all good aviators.

Rgds SOS

[John Farley]

Courtney

Did the double ejection cause the aircraft to pitch down? Interesting answers there. Of course it did. Newton's Third Law of Motion

Sorry young man I can't agree with you there. The force from the seats is only applied for very small fraction of a second so the nose down velocity resulting from the acceleration would not be measurable. Hardly time for Mr N to realise he was involved.

I would expect the aircraft was probably out of trim nose down when they let go of the stick but even if it wasn't loosing the canopy would cost a lot of lift from the front end.

JF

[Ewan Whosearmy]

BOAC and Galaxy Flyer

Do tell us more!

[BOAC]

Sorry, don't have the time....................

[Courtney Mil]

Originally Posted by John Farley

The force from the seats is only applied for very small fraction of a second so the nose down velocity resulting from the acceleration would not be measurable.

The time for which the force is applied is short indeed, but the force is huge. Huge enough to propel the seats and occupants out of the aircraft very quickly. Impulse=force x Dtime. The impulse isn't trying to accellerate that whole aircraft downwars (in this case) it is just applying a derotational force to two points well forward of the c of g - quite a long moment.

Therefore, a bag-seat will impart sufficient force to the aircraft to cause it to pitch down. If the force act long eonugh to accellerate the seats, it has time to act on the aircraft too. Newton never sleeps. Old Chap.

[BOAC]

Do we know if they were rocket seats? If so, the force is not that big.

[Courtney Mil]

Agreed, BOAC. Rocket only seats behave very differently. Biggest pitch down from a pure bang seat, less from banng and rocket, virtually none from rocket only.

The two ejection gun barrels sticking out of the aircraft suggest there is a bang involved, backed up by my belief that it's fitted with a variant ofthe MB Mk10.

So the Third Law would apply. Twice.

[BOAC]

Indications are that the seat is an 'HTY-7A rocket ejection seat' - 'rocket-assisted'. (I still believe my and JF's explanation for the pitch down is the most likely - ie trim.)

[Courtney Mil]

Well, I suppose if the pilot wasn't a QFI the aircraft MAY have been very slightly out of trim, which could ADD to the ejection pitch-dow.

[BOAC]

He was only 4 years old - give him a break!

[Arcanum]

This in cockpit video of a hawk ejection from a few years ago shows the nose being forced down during ejection. Still had about 140-kts on the HUD at ejection time.

Bird Strike and Ejection in a Hawk Jet - YouTube

[John Farley]

I must remember to ask MB why it does not happen with their test Meteor. Or for that matter why it did not happen with the test Canberra of SME Flight at RAE in the 50s (talk about a gun). 'Spect they will say we did not fit the canopy and the gun barrel is/was only pressurised for a terribly short time. Hey ho.

[Fareastdriver]

In that case why does a .45 pistol hurt my wrist so much when I pull the trigger.

A 170lb pilot leaving an aircraft on a Mk 3 seat leaves the end of an 8 foot gun at 80 ft/sec. That is a 25G acceleration. 25X170 lbs is a 4,250 lbs force at the front of the aircraft. That is 2 tons hitting it in 1/10th of a second. It used to, as has been proved, moved Javelins.

Fly something like a B25 Mitchell and have a 4,000lb bomb inadvertantly land on your cockpit. You would certainly notice that.

MB , and others, had the advantage of expecting it

[rigpiggy]

cause your limpwristed.

[wiggy]

That is 2 tons hitting it in 1/10th of a second. It used to, as has been proved, moved Javelins.

On the other hand there are certainly plenty of instances of aircraft continuing to fly some considerable distance after a crew member has ejected, even using a pure gun seat (e.g. The "Tintagel Hunter" and the Lightning that had to be abandoned off Valley with a gear problem at Valley in ?'79), so perhaps at reasonable air speeds the pitch down is not as pronounced as one would think - best I leave the theory behind that to the likes of JF.

OTOH a gun/rocket seat firing certainly produces a jolt and a lot of noise but doesn't always produce a large pitch down.

MB , and others, had the advantage of expecting it

Well FWIW I wasn't ....... even so the aircraft didn't dramatically didn't pitch down..and in fact it kept going for several miles.