Abstract: An integral rocket and ramjet engine (16) comprises, in flow series, an intake duct (18) for aerodynamically compressing air, a port cover (30), a combustion chamber (20) and a propelling nozzle (22). The port cover (30) in a first position prevents air from entering the combustion chamber (20) and enables a rocket charge (24) to be burnt in the combustion chamber (20) thereby accelerating the engine to sufficient velocity for ramjet operation. The port cover (30) is movable axially to a second position when the rocket charge (24) is spent to allow compressed air into the combustion chamber (20) and the engine (16) to operate as a ramjet. In the second position the port cover (30) provides a quiet zone (52) which is substantially shielded from the main flow of air into the combustion chamber. Combustion equipment such as primary and main fuel manifolds (42,46) and flame gutters (50) are also movable with the port cover (30).

Abstract: A float and flag assembly for use by divers includes a buoyant annular ring or member mounted on an elongated staff. A flag or signalling device is mounted on the staff at one end thereof. A lead weight or the like is secured to the other end of the post.