F 35 Landing - Tailhook

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.

Prior to making an "arrested landing", the pilot lowers the hook so that it will contact the ground as the aircraft wheels touch down. The hook then drags along the surface until an arresting cable, stretched across the landing area, is engaged. The cable lets out, transferring the energy of the aircraft to the arresting gear through the cable. A "trap" is often-used slang for an arrested landing. An aircraft which lands beyond the arresting cables is said to have "boltered." Occasionally, the tailhook bounces over one or more of the wires, resulting in a "hook skip bolter."

In the case of an aborted land-based takeoff, the hook can be lowered at some point (typically about 1000 feet) prior to the cable. Should a tailhook of an aircraft become inoperative or damaged, naval aviators have limited options: they can divert to shore-based runways if any are within range, or they can be "barricaded" on the carrier deck by a net that can be erected.

The tailhook was first demonstrated at sea on 18 January 1911 by the aviator Eugene Ely, having successfully landed aboard the armored cruiser USS Pennsylvania with the aid of the device. It was not until the early 1920s that a practical system, paired with deck-mounted arresting gear, was devised and put into use. During the 1930s, numerous vessels were thus equipped, permitting the use of increasingly heavy combat aircraft at sea during the Second World War. Following the introduction of jet-powered aircraft during the 1950s, arrestor technology was further advanced to permit aircraft operating at greater speeds and weights to land aboard aircraft carriers. The system has continued to see widespread use into the twenty-first century.

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.

A large number of land-based fighters are also outfitted with tailhooks, which are intended 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.