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stilton
29th May 2008, 06:12
I seem to remember a story of an carrier catapult shot gone wrong resulting in the aircraft dribbling off the end with insufficient speed to fly.

Tale went on to relate how the pilot waited until the ship had gone past 'overhead' whilst descending 'below sea level' and breathing oxygen, then making a succesful underwater ejection

Anyone with more details ?

Pontius Navigator
29th May 2008, 06:31
Here's one but not the one I think you mean:

http://www.******************************/seahawk/history.html

The mdc fitted to Buccaneers was to facilitate underwater ejection after the loss of the OC of 803 in a Scimitar.

http://www.******************************/scimitar/history.html

Google is your friend. Keep googling.

green granite
29th May 2008, 07:13
http://www.******************************/seahawk/history.html

Are we suffering from censorship. ????????

Pontius Navigator
29th May 2008, 07:38
R a t h e r l o o k s l i k e i t

http://www.t h u n d e r-a n d-l i g h t n i n g s.co.uk/b u c c a n e e r/h i s t o r y.html

I think it is an attempt to stop us rabble rousers posting links to non-U sites in an attempt to seduce the impressionable away from pprune.

jimgriff
29th May 2008, 07:40
Yes, it was tried tested and fitted to aircraft of the Royal Naval Fleet Air Arm. One of the most famous of these was the Blackburn Buccaneer.



Below is an overview of the system fitted from a technical manual of the era.



MARTIN BAKER PATENT FULLY AUTOMATIC UNDERWATER EJECTION SYSTEM. JUNE 1965



The Martin-Baker patent underwater escape mechanism was designed to provide fully automatic escape facilities for aircrew who had to ditch their aircraft and were rendered unconscious on striking the water, It was capable of ejecting the airman from the aircraft, separating him from his seat and supporting him on the surface by his fully inflated life-jacket, no action whatever being necessary on his part.

The system consisted of a main air bottle open to water pressure via a stainless steel pipe to a convenient point on the aircraft skin. When the sinking aircraft reached a depth of approximately 13 feet the pressure on the valve diaphragm removed the restraint on the firing pin, allowing it to descend under spring pressure and fire the cartridge in the head of the bottle.

The compressed air is thus released and is piped to two places, the lower end of the ejection gun and the drogue gun trip rod release unit.

The air entering the bottom of the ejection gun forces the inner and intermediate piston tubes upwards, unlocking the seat and ejecting if from the aircraft but without firing the ejection gun cartridges.

The air to the drogue gun trip rod release unit forced a wedge shaped plunger out of its housing and in so doing releases the drogue gun trip rod preventing the gun from being fired. At the same time the plunger struck a linkage which withdrew the guillotine sear thus severing the link line between the drogues and parachute. The movement of the plunger uncovered a port in the unit allowing the air to proceed to the specially modified life-jacket inflation bottle via the personal equipment connector. The bottle was thus actuated and the life-jacket inflated.

As the seat rose on ejection the time-release unit was tripped in the normal manner and ran for a period of 1.5 seconds. At the end of this period the plunger descended and struck the harness release lever. On rotating, the harness release lever released the harness locks and at the same time it operated the C.0.2 bottle mounted on the starboard side of the seat, the gas being piped to two bladders, one behind the parachute pack and the other, underneath the dinghy pack.

The action of these two bladders was to push the occupant from the seat and, as the harness locks had been released by the time release unit and the parachute withdrawal line severed by the guillotine, a clean separation was initiated. The occupant was thus free to float to the surface unencumbered by an opened parachute and supported by his life-jacket until a rescue could be effected.

The system could be rendered inoperative by a handle attached to the main air bottle which, through a linkage, operated a slide valve. When the slide valve was moved to the inoperative position it blanked off the delivery ports to the base of the ejection gun and the drogue gun trip rod release unit. At the same time it opened a port so that, should the main air bottle inadvert*ently operate the air will exhaust to the atmosphere,

A secondary escape operating mechanism was fitted. On operating the emergency handle situated on the starboard thigh guard, the sear is withdrawn from the firing body which allowed the striker to go forward and fire the cartridge. The gas pressure impinges on the valve diaphragm which removes the restraint on the main air bottle firing pin thus initiating the escape sequence.

The underwater escape equipment in no way affected the procedure for an airborne ejection which could be accomplished in the normal manner. Standard items of the ejection seat which had been slightly modified for underwater escape included the ejection gun and the personal equipment connector. The former had a plug fitted to the lower end of the inner piston tube and held in position by two shear rivets. This had the two fold purpose of minimizing the amount of air required and preventing the compressed air from rupturing the diaphragm of the primary cartridge and possibly causing it to fire. A sear of a different design was fitted to the firing unit in the ejection gun breech, this allowed the firing cable to disconnect when the ejection gun extended, thus preventing the firing of the primary cartridge. The personal equipment connector was modified to include the air line to the life-jacket inflation bottle and incorporates a ball valve in the aircraft portion, held open when the seat and aircraft portions are connected and automatically closed to conserve the air when the seat and aircraft portions separate.

Pre flight Action, Airborne ejection sequence and Action after Flight are perfectly standard. Manual separation and free bale out in the event of damage to the seat was again similar to the standard guillotine seat.



SAFETY PRECAUTIONS

One extra, safety pin was provided in addition to the standard safety pins; for rendering the emergency firing handle inoperative, or for placing in the sear of the secondary operating firing unit when necessary.

A spring-loaded protection flap, which covers the ejection gun primary firing unit, was attached to the upper rear face of the pilots ejection gun. Integral with the flap was a window for visual inspection of the correct attachment of the firing cables to the sear.

Incorporated in the main air bottle operating head was a safety slide which, when in the engaged position, obstructed the downward movement of the bottle firing pin. When the bottle was installed in the aircraft the safety slide was locked out of engagement by fitting a pin into the hole provided in the safety slide.



On 13th October 1954 Lt McFarlane stayed in his Wyvern (underwater) until the carrier had passed over him before ejecting and survived.
Wyvern TF1 VZ783 (X) 813 sqdn (HMS Albion)

beardy
29th May 2008, 08:38
At the museum on the airfield in Goa the Indian Navy claim that the first successful underwater ejection was from a UK built, Indian operated, aircraft (sorry can't remember the type) from their carrier.

desk wizard
29th May 2008, 10:03
http://www.bharat-rakshak.com/NAVY/History/1970s/Pasricha.html

Commander Peter Debras, Indian Navy

Matt Skrossa
29th May 2008, 10:36
The Principal Medical Officer at Culdrose in 77-78 was Surg Captain Davidson, who when he was a young Lt doc took part in live underwater ejection trials! A fascinating man to talk to who helped advance the safety of others whilst putting himself in unknown danger, top man.

ORAC
29th May 2008, 10:50
At the museum on the airfield in Goa the Indian Navy claim that the first successful underwater ejection was from a UK built, Indian operated, aircraft (sorry can't remember the type) from their carrier. Aircraft Underwater (http://www.bharat-rakshak.com/NAVY/History/1970s/Pasricha.html)

jimgriff
29th May 2008, 11:28
It seems that the Indian Navy info boards need updating as Lt McFarlane had ejected from a submerged aircraft 22 years before them!!

TBM-Legend
29th May 2008, 11:37
Oz Navy A-4G Skyhawk went into the drink and actually went under the Melbourne and u/water ejection I think SBLT Barry Evans.. circa 1972:eek:

beardy
29th May 2008, 11:49
Next time I'm in Goa I'll tell them! Here are 2 lucky guys:

http://www.youtube.com/watch?v=xz8fOZxIdVg

Schiller
29th May 2008, 14:41
The system described by Jimgriff I remember well. However, its claim to assist unconscious aircrew was somewhat exaggerated, for two reasons. Firstly, it was necessary to get rid of the hood first, and secondly, when you bubbled up to the surface the lower end of your personal equipment connector was still under water. Still, you had the pleasure of drowning in the open air, I suppose.

In fact, the underwater seat reached the squadrons at the same time as the zero-zero seat, so it made much more sense just to use the normal ejection system if you were going over the side.

stilton
30th May 2008, 03:46
Incredible stuff..

L J R
30th May 2008, 03:54
The Oz Navy Chap is a fact from a few posts ago, but I seem to recall that he sat in the 'live' and 'activated seat' he later scrambled out after the large prop was seen to pass overhead - ie not an actual ejection....

ehwatezedoing
30th May 2008, 16:40
If you dig "aircrew stories" into: http://www.ejectionsite.com/
You will find an impressive one done at night (take about your worst nightmare) from a A-7 in 1969.
A sudden blast of brilliant light blinded me-the seat's rocket motor had fired following a built-in sequencing delay. In an instant, I was out of the cockpit and clear of the seat, though still submersed in the cold, dark water of the Pacific.
....
I couldn't breath. The water had forced the oxygen mask down around my chin and the emergency oxygen bottle in the seat pan was useless. for the first time, panic set-in and I became totally disorientated-I couldn't tell up from down. It was as if I had been shot out of a high-powered cannon into a pool of jet-black ink