in fairly ready supply at this stage of the war. An official trial of the Mk I Projector took place in February 1940 with resounding success. An order was placed by the Royal Navy for 1,000 of the Mk I models and the weapons proved just as successful in action; the first confirmed success was reported only three weeks after the initial batch was sent out when a Heinkel aircraft was damaged. While direct hits were rare, the bombs fired by the projector displayed an unexpected property — the explosion would leave a large puff of black smoke, absent from ground-based explosions from similar grenades. Firing a large number in quick succession gave the impression to incoming Luftwaffe pilots that the target vessel was armed with something far more deadly than the Holman Projector, deterring or disrupting attacks, or convincing the aircraft's crew an attack at greater range would be prudent, with a commensurate decrease in accuracy. Mk II The Mk II Projector was developed after a request from the Royal Navy for a version that could be fired using steam in place of compressed air, since the steam-engined trawlers (both fishing and minesweeping) had the former in plentiful supply. The Stokes design of the Mk I needed to be abandoned for this, since the harsh weather experienced by the trawlers invariably rusted the valves of the pneumatics. When steam was used in such a system, the water would condense in the pipes and prevent firing of the weapon. To solve this, a firing trigger was added, in place of the Stokes design in which the round would be fired automatically. The new version was fitted to a wide variety of ships, from destroyers to minesweepers and motor gun boats: to demonstrate the weapon's versatility, a trial was arranged in Aldershot, Hampshire before Prime Minister Winston Churchill. No Mills rounds were brought, as it was assumed that some form of ammunition would be provided by the British Army, who were overseeing the trials but these were overlooked and the trial was set to be delayed until one officer thought to bring out the bottles of beer that were to have been served at lunch: the smooth bore of the Projector allowed even these irregular projectiles to be fired successfully, with all striking the target with an explosion of glass and foam. The Prime Minister commented on the weapon afterwards, describing