Engine protection system for recoverable rocket booster

In a liquid rocket booster for a space vehicle that has a turbopump driven rocket engine and a parachute system which permits a controlled descent of the liquid rocket booster in a generally nose down attitude as it nears the earth for recovery in a salt water body after separation at a predetermined time from the space vehicle, which salt water body can cause impact damage and corrosion damage to the rocket engine, the improvement which comprises:

• inflatable water impermeable bag means secured in a deflated state to at least a portion of the lower outer perimeter of a skirt surrounding components of the rocket engine including the nozzles;
• spring means in its normal state urging the bag means to a deployed state;
• actuable locking means to lock the bag means in a deflated state and in a deployed state;
• and
• actuable gas pressure means which is actuated when the lock means has released the bag means from its deflated state so that said spring means is permitted to urge the bag means from its state to a deployed state which permits the bag to sealingly extend against the full perimeter of the skirt and to be inflated by gas pressure from the gas pressure means thereby precluding entry of salt water into the rocket engine after the liquid rocket booster has landed in a salt water body.