Great idea but too much pressure
the idea was to find a source of stored gas that would activate the parachute air cylinder when the solenoid was triggered by the tilt switch. I thought an oversize, 16g, sodastream bulb would be ideal, and calculated the volume of gas should fill the air cylinder 4 times over so plenty to spare.
Bought a small tyre inflator adaptor to hold the bulb, and a mat made an adaptor to take the gas from the tyre inflator into the SMC tubing.
All set up direct not through the solenoid and ready to test it out, i opened the tyre inflator valve and started feeding in the gas, the cylinder moved as required, although as it wasnt a sudden rush like when the solenoid opens against the pressure, then it when silent for a second before the air tubing bulged and burst, with the sound of a shotgun going off.
I was deaf for 30 minutes!
So its Plan B, a paint ball cylinder or similar that i will inflate/regulate to 100psi and use that to fire off the air cylinder, i have no idea what pressure is in a sodastream bulb, but damn high is a good guess. Mr Google tells me 800psi.