Tailhooks on military aircraft are a common sight … although we tend to only think of them as being part of aircraft landing on aircraft carriers, not those landing on runways. This Reader Mail comes from Damian Willis in the Great White North (aka: Canada) who asks, “I recently spent some time watching US Air Force F-16 Falcons and F-15 Eagles coming and going outside of Las Vegas and noticed what I thought were tailhooks mounted on them. Why do Air Force jets have tail hooks?”
Damian, what you saw mounted to the aft of these aircraft is in fact a tailhook. The tailhooks on Air Force aircraft, including the F-15, F-16, F-117 and F-22, serve two purposes, assisting in emergency landing situations and to secure the aircraft during maintenance engine testing.
Many U.S. Air Force runways have an emergency arresting cable hidden in a recess of the runway surface. Should an aircraft suffer a hydraulic problem, brake failure, or need to abort a take off on a short runway, among other potential situations, a pilot will call “cable, cable, cable,” alerting the tower to raise the arresting cable from its runway recess.
The tailhook mounted on an Air Force jet, while serving the same basic purpose of that mounted to a Navy or Marines aircraft, is different in a number of ways. An Air Force tail hook is held in position by a safety pin. When a pilot deploys the hook a pneumatic system disengages the pin and thrusts the hook down, keeping the hook approximately eight inches from the ground to catch the raise arresting cable. Unlike an aircraft carrier arresting cable, a ground runway arresting system slows an aircraft, pulling in to a stop, over a much longer range, rather that instantly yanking the aircraft to a stop. Tailhooks on Air Force aircraft typically are non-retractable and need to be put back into place by ground crews (although some F-15Es and F-22s are now fitted with actuators allowing them to be retracted by the pilot)
The most frequent use of the tailhook mounted to an Air Force jet is not however related to stopping aircraft, it is to secure an aircraft to a stationary position while mechanics run engine tests at full throttle in a Hush House following maintenance to the engines.
While some Air Force jets have tailhooks mounted beneath them, these aircraft cannot land on an aircraft carrier for two reasons. The first reason, the major reason, is the landing gear on Air Force jets cannot withstand the impact of landing on a ship’s deck and would collapse upon slamming onto the deck. The second reason, is the tailhook on an Air Force jet has a greater distance from the ground than a Navy or Marines aircraft, so they would have a significant challenge in trapping the arresting cable without ripping their tailhook from their aircraft and doing significant damage to their jet.
So there you go … why Air Force jets have tailhooks.