Homework / test English to Swedish Tech/Engineering Aerospace / Aviation / Space Emergency egress from an aircraft

In a text about emergency egress from an aircraft using an ejection seat.
BTRU cartridge (Barostatic Time-Release Unit). The word "Cartridge" is also found in the following contexts:
The ejection seat initiator cartridge
The ejection gun initiator cartridge
Secondary cartridge in the ejection gun
Drogue gun primary cartridge
The manual override cartridge in the lower harness release system

I would appreciate help with other terminology in these examples if possible.