21 April 2010

During times of war, operational necessities sometimes breed unusual solutions- in the Second World War the most famous of these was the Japanese kamikaze. Though no Allied airmen were ever committed to a formal suicide mission, the desperation of the in its first half did lead to one program that probably comes as close as can be to a suicide mission- the Catapult Armed Merchantmen (CAM ) ship program put in service by the British during the early days of the Battle of the Atlantic.

Being an island nation, Great Britain was dependent upon maritime trade and in particular, dependent upon the Atlantic convoys from the United States that delivered not just weapons and armaments, but also food staples and fuel. As the Battle of the Atlantic intensified in 1941, the German U-boat menace began taking its toll on merchant shipping that was Britain's wartime lifeline. However, the U-boats were only part of the problem as the Luftwaffe's long-range Focke Wulf Fw 200 Condor long range patrol bombers also preyed on the convoys and also provided eyes for the submerged U-boat wolfpacks.

The solution was the Catapult Armed Merchantmen and the Hawker Sea Hurricane. Approximately 36 cargo ships were fitted with a rocket-driven catapult mounted on the forecastle of the ships. The catapult was mounted in a fore-aft orientation and slightly offset to port to which the Sea Hurricane was mounted. The first Sea Hurricane variants only had local reinforcements and attachment points to the catapult trolley. Two pilots were assigned to each CAM ship and alternated 12 hour shifts. Once a Condor had been sighted, the alert pilot strapped into the Sea Hurricane and the rocket catapult fired, moving the Sea Hurricane and the expendable trolley at 3.5Gs while the pilot had the engine running at full power.

The CAM ship's forward structures were shielded to prevent damage caused by the rocket blast. Once committed to launch, the pilot had to use 1/3 starboard rudder to overcome the Hurricane's tendency to swing to port at full throttle. In addition, 1/3 flap was used to help get the Sea Hurricane airborne with the trim tabs set to neutral. If too much back pressure got applied during launch, the plane would stall and fall into the sea, so pilots would brace their right arm by shoving their right elbow against their hip to prevent inadvertent back pressure from the G-forces of the launch.

Launching the Sea Hurricane and engaging the Condor was the easy part of the mission. Since there was no way of returning to the ship, the pilot only had two choices- either ditch near the ship or hope there was enough fuel to head for land. Ditching a Sea Hurricane wasn't a great option- the bottom mounted radiator scoop easily flooded and the aircraft would sink quickly. If land was too far away to reach, the preferred option was to bail out rather than ditch the aircraft. Timing was of the essence, as exposure in the cold North Atlantic required an expeditious rescue out of the water. Later versions of the Sea Hurricane were fitted with two 44-gallon underwing tanks to extend the range and make reaching land more feasible.

As a result of the risks to the pilot in launching the Sea Hurricane, it was considered a last resort as most convoy captains didn't want the rocket flash to attract the attention of the Condors. By 1943, though, the CAM ships and their risky missions were superseded by the arrival of the first small escort carriers called MACs- Merchant Aircraft Carriers. The MACs were small escort carriers that lacked any hangar facilities and carried its Sea Hurricane complement (usually five) on the deck exposed to the elements. As a result, the Sea Hurricanes were only good for about 30 flying hours before saltwater corrosion took its toll. Although Sea Hurricanes were also deployed on the larger fleet carriers of the Royal Navy, handing idiosyncrasies on landing made them quickly superseded by purpose-built carrier fighters.

Source: Aeroplane Monthly, April 2010, Volume 38, No. 4. "Fierce Wind over the Deck" by Philip Jarrett, p36-40.

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