The Sea Vixen had a crew of two, pilot and observer. The observer was positioned in an enclosed area on the starboard side of the fuselage-known as the 'coal-hole.'
Above him was an entry hatch with a small window.
Both crew members were supplied with a Martin Baker Mk 4 ejection seat. In an emergency, the normal sequence was (for the observer) to pull the protective screen down in front of his face, and through a safety interlock, cause the hatch to be automatically jettisoned, which in turn allowed the ejection seat to be fired. If the hatch did not depart, the seat could not be fired.
I've been reading about the exploits of Allan Tarver (pilot) and John Stutchbury (observer) in a Sea Vixen flying over the port of Beira on the 10th of May 1966.
John Stutchbury Allan Tarver
A long story, but John Stutchbury lost his life as a result of the safety interlock failing. He manually jettisoned the hatch but could not fire the ejection seat. Tarver inverted the Vixen (twice!-with both engines out) hoping Stutchbury could bail out manually.
It all went wrong.
The court of enquiry concluded that it was the hatch jettison system that was at fault, not the ejection seat. All Sea Vixens were modified to include a frangible fibreglass hatch over the observer's cockpit so that from then on, when fired, the ejection seat went straight through it.
A long intro to a question, but do modern ejection seats 'punch' through frangible canopies or does the canopy depart first?
Above him was an entry hatch with a small window.
Both crew members were supplied with a Martin Baker Mk 4 ejection seat. In an emergency, the normal sequence was (for the observer) to pull the protective screen down in front of his face, and through a safety interlock, cause the hatch to be automatically jettisoned, which in turn allowed the ejection seat to be fired. If the hatch did not depart, the seat could not be fired.
I've been reading about the exploits of Allan Tarver (pilot) and John Stutchbury (observer) in a Sea Vixen flying over the port of Beira on the 10th of May 1966.
John Stutchbury Allan Tarver
A long story, but John Stutchbury lost his life as a result of the safety interlock failing. He manually jettisoned the hatch but could not fire the ejection seat. Tarver inverted the Vixen (twice!-with both engines out) hoping Stutchbury could bail out manually.
It all went wrong.
The court of enquiry concluded that it was the hatch jettison system that was at fault, not the ejection seat. All Sea Vixens were modified to include a frangible fibreglass hatch over the observer's cockpit so that from then on, when fired, the ejection seat went straight through it.
A long intro to a question, but do modern ejection seats 'punch' through frangible canopies or does the canopy depart first?
