I assume the catapult systems shown in the film are steam pistons that build up pressure, before being released and flinging the aircraft forward to launch velocity?
So what would happen if the release mechanism holding the pressurised piston were to fail before the crew were ready to launch?
I assume there are additional safety mechanisms.... or would it just fling the aircraft forward and (potentially) off the carrier into the sea?
There's what is called a holdback bar, or holdback fitting.
If you watch flight deck launch videos you will see an airman duckwalking up behind the nose wheel and attaching the fitting.
The holdback fittings are designed to sheer and break at specified tensions, insuring a launch only once proper tension is applied.
It allows the jet to go to full Mil power or afterburner without hurtling down the cat track and out of the cat shuttle.
Steam pressure to the catapult piston itself is not applied until the catapult is fired. The pressure builds up in steam accumulators until they have proper pressure and then is applied to the piston once fired.
There are so many checks and double checks that there is almost no chance of the shuttle being fired before the crew is ready. The very last step is the Pilot saluting the Catapult Officer signifying his readiness, the Cat Officer makes a final check of all personnel to insure everything is still clear and then he signals for the cat to be fired.
There are possibly things that can go wrong. The cat could be set for the wrong weight by accident and thus not enough steam to boost the plane to flyaway speed. or the cat could suffer a casualty on firing and lose pressure causing the same thing.
This is referred to as a Cold Cat or Soft Cat Stroke. This leaves the plane at the end of the stroke either just barely at the edge of stall/flying speed, or worse... below it.
On this video, a Prowler recieves a cold cat and slowly trundles down the track.
They kniw there is zero chance to fly away and the four man crew punches out the instant they reach the bow. Still one of the crew loses his life.
https://youtu.be/UeZKyGDo5Io
Lex wrote about a bad Cat shot. I'll see if I can find it and repost it here.
I joined the Navy to see the world, only to discover the world is 2/3 water!
The holdback fittings are designed to sheer and break at specified tensions, insuring a launch only once proper tension is applied.
Steam pressure to the catapult piston itself is not applied until the catapult is fired. The pressure builds up in steam accumulators until they have proper pressure and then is applied to the piston once fired.
the Cat Officer makes a final check of all personnel to insure everything is still clear and then he signals for the cat to be fired.
The cat could be set for the wrong weight by accident and thus not enough steam to boost the plane to flyaway speed.
Tomcats, hornets and Super Hornets (and I assume F-35cs) use a repeatable release holdback bar. It releases at a set tension and is reset for the next jet. I used to work in the shop on the carrier that tested and adjusted these.
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