Arrestor hook

A tailhook, arresting hook, or arrester hook is a device attached to the empennage (rear) of some military fixed-wing aircraft. The hook is used to achieve rapid deceleration during routine landings aboard aircraft carrier flight decks at sea, or during emergency landings or aborted takeoffs at properly equipped airports.

On January 18, 1911, Eugene Ely landed his Curtiss pusher airplane on a platform on the armored cruiser USS Pennsylvania anchored in San Francisco Bay. Ely flew from the Tanforan airfield in San Bruno, California and landed on the Pennsylvania, which was the first successful shipboard landing of an aircraft. This flight was also the first ever using a tailhook system, designed and built by circus performer and aviator Hugh Robinson. Ely told a reporter: "It was easy enough. I think the trick could be successfully turned nine times out of ten."

The tailhook is a strong metal bar, with its free end flattened out, thickened somewhat, and fashioned into a claw-like hook. The hook is mounted on a swivel on the keel of the aircraft, and is normally mechanically and hydraulically held in the stowed/up position. Upon actuation by the pilot, hydraulic or pneumatic pressure lowers the hook to the down position. The presence of a tailhook is not evidence of an aircraft's aircraft carrier suitability. Carrier aircraft hooks are designed to be quickly raised by the pilot after use. Many land-based fighters also have tailhooks for use in case of a brake/tire malfunctions, aborted takeoffs, or other emergencies. Land-based aircraft landing gear and tailhooks are typically not strong enough to absorb the impact of a carrier landing, and some land-based tailhooks are held down with nitrogen pressure systems that must be recharged by ground personnel after actuation.

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