Victor Canopy Escape Hatches
I have only just caught up with this interesting thread. I do not recognise post 64 in the thread - are there some PMs about - if so it would be interesting to know what they say about Marham Stn Cdrs. Most were good but some were not.
Back to the thread.
The following edited quotation is copyright and may not be quoted or used in any other public forum, book, magazine or other publication without my written permission.
"The pilots escape hatches were not plug fits into the airframe, and were fitted with seals to maintain cabin pressurisation. The seals were inflated with air from an 1800 psi bottle, reduced to 15 psi. If this pressure was lost, one could screw a tool into the pressure reducing valve allowing cabin pressure air into the seal in an attempt to maintain cabin pressure. I only had to do this once and it worked.
In the early Victor days, the aircraft were not cleared for full pressurisation as the cabin floor had to be reinforced. We routinely flew around with cabin altitudes above 15000 feet. It was not until around 1961 that the B1s and B2 were cleared for full operation of the cabin pressurisation system. Within months, I think on three sorties, the main cabin door blew open in flight, and twice the entire door and associated structures left the aircraft. This resulted in changes in the SOP, and a fleet modification to provide indications that the main crew door locks were in a "geometrically" locked position. However, the most significant modification was the introduction of a cabin pressure differential gauge. When the whole door structure and blast shield left the aircraft, it meant that crew members could not abandon the aircraft except in a very low IAS situation. Thus it became the drill to check the cabin differential was below 3 1/2 psi (I think) before attempting to open the door on the emergency "blow open" system, so the blast shield would not be lost. I and other crews then thought that in the event of an extreme emergency such as a mid air collision, the quickest way to de-pressurise the cockpit to allow safe door opening would be for the co-pilot to eject dropping the differential to zero.
It should be noted that the canopy jettison was a key stage in the firing sequence of the ejection seat. The seat could not fire unless the canopy had departed the aircraft. To achieve this, when a canopy jettison handle or ejection seat handle was activated, the first thing that happened was that a cartridge was fired into a cylinder containing a piston connected by linkage arms to all the latches holding the canopy firmly in the closed position. The gas pressure via the linkage would open all the latches, and assisted by the airflow, two spring loaded jacks would kick the canopy open and away from its stowage. This system was proved when a navigator inserting the ejection seat safety pins while an aircraft taxied in after a sortie, accidentally pulled on the canopy jettison cable - the cartridge fired, the springs pushed, and the canopy ended up about 100 feet from the aircraft! The SOP for removing and inserting the pins was changed after this incident.
Now to the Victor 1 accidental firing of the canopy jettison system. It has been well described earlier, but my recollection was slightly fuller. The First Pilots ejection seat had a handle on the right hand side of the seat to raise and lower it. On the cockpit structure to the left of the seat was a "Grip" handle which had to be pulled upwards to fire the canopy jettison cartridge. The navigator, who was not strapped into the seat, wanted to raise the ejection seat and asked what to do. He was told to pull the lever up - he had his hand on the canopy jettison, and pulled it up and the cartridge fired as advertised. Fortunately for the crew, it emerged that there was not sufficient power or leverage from the piston to drive the locks open. When the latches were holding the canopy closed with cabin pressure exerting a load of several tonnes against them, there was too much friction to allow the latches to unlock.
A wiser crew and a wiser Victor Force, resulted. Abandoning the aircraft could only be safely undertaken when the door and canopies were not subject to full pressurisation loads. Drills were changed, and thankfully, apart from Keith Handscombe's mid-air collision, no other high altitude abandonment was ever required."