Aircraft catapult
Different means have been used to propel the catapult, such as weight and derrick, gunpowder, flywheel, compressed air, hydraulic, steam power, and solid fuel rocket boosters.
Historically it was most common for seaplanes to be catapulted, allowing them to land on the water near the vessel and be hoisted on board, although in the Second World War (before the advent of the escort carrier) conventional fighter aircraft (notably the Hawker Hurricane) would sometimes be catapulted from "catapult-equipped merchant" (CAM) vessels to drive off enemy aircraft, forcing the pilot to either divert to a land-based airstrip, or to jump out by parachute or ditch in the water near the convoy and wait for rescue.
Aviation pioneer and Smithsonian Secretary Samuel Langley used a spring-operated catapult to launch his successful flying models and his failed Aerodrome of 1903.
[1] Likewise the Wright Brothers beginning in 1904 used a weight and derrick styled catapult to assist their early aircraft with a takeoff in a limited distance.
On 14 December 1924, a Martin MO-1 observation plane flown by Lt. L. C. Hayden was launched from USS Langley using a catapult powered by gunpowder.
Some carriers were completed before and during World War II with catapults on the hangar deck that fired athwartships, but they were unpopular because of their short run, low clearance of the hangar decks, inability to add the ship's forward speed to the aircraft's airspeed for takeoff, and lower clearance from the water (conditions which afforded pilots far less margin for error in the first moments of flight).
CAM ships carried a Hawker Sea Hurricane 1A,[i] dubbed a "Hurricat" or "Catafighter", and the pilot bailed out unless he could fly to land.
Commander C. C. Mitchell, RNV, recommended a steam-based system using a slotted cylinder as an effective and efficient means to launch the next generation of naval aircraft.
Larger planes, such as the E-2 Hawkeye and S-3 Viking, require a catapult shot, since their thrust-to-weight ratio is too low for a conventional rolling takeoff on a carrier deck.
Electromagnetic catapults place less stress on the aircraft and offer more control during the launch by allowing gradual and continual acceleration.
Electromagnetic catapult would be more energy efficient on nuclear-powered aircraft carriers and would alleviate some of the dangers posed by using pressurized steam.
[21][22] From 1929, the German Norddeutscher Lloyd-liners SS Bremen and Europa were fitted with compressed air-driven catapults designed by the Heinkel Flugzeugwerke to launch mail-planes.
The flying boat would land on the open sea, be winched aboard by a crane, refueled, and then launched by catapult back into the air.
From September 1934, Lufthansa had a support ship at each end of the trans-ocean stage, providing radio navigation signals and catapult launchings after carrying aircraft out to sea overnight.
This was possible as the flying boats could carry more fuel when they did not have to take off from the water under their own power, and cut the time it took for mail to get from Germany to Brazil from four days down to three.
From 1936 to 1938, tests including the Blohm & Voss Ha 139 flying boat were conducted on the North Atlantic route to New York.
Schwabenland was also used in an Antarctic expedition in 1938/39 with the main purpose of finding an area for a German whaling station, in which catapult-launched Wals surveyed a territory subsequently claimed by Germany as New Swabia.
After World War II, Supermarine Walrus amphibian aircraft were also briefly operated by a British whaling company, United Whalers.
