Reader Mail : Why Do Air Force Jets Have Tailhooks?
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.
Happy Flying!
Benji,
I included the F-117 as there are multiple credible sightings of the aircraft flying in Nevada post-retirement.
I am not sure in what capacity the aircraft are flying , but they seem to be I officially in the air.
Happy Flying!
-Fish
The primary USAF arresting barrier is the BAK-12. It is not hidden in a recess of the runway. It is actually held about 3 inches off the runway surface by rubber disks spread about every 4 feet across the runway. These are referred to by the barrier maintenance crew as doughnuts. Generally, when there’s a problem with the brakes or hydraulic system the pilot is aware of it prior to landing and declares an emergency. The tower notifies the barrier maintenance crew and they head for the runway.
The aircraft touches down with the hook down and it catches the cable. The cable is attached on both sides to a nylon tape that leads to a reel that is attached to a braking system. These are located about 150 ft. off the runway in a wooden shed. If the crew has enough lead time they will have at least one person on each side of the runway at the shed with the doors opened because the brakes produce a lot of dust. There’s also a point man located off the side of the runway at about where the aircraft will stop, usually about 950 feet from where the cable crosses the runway.
After the aircraft stops the point man signals the pilot to release his brakes and then signals the two operators to rewind the tapes about 25 feet or so then signals them to stop. The aircraft continues backward and the tail hook disengages the cable. The point man signals the pilot to raise his hook and taxi away. If there was a visual problem with the aircraft, like a leak of some kind, the point man would signal the pilot to shut his engine(s) down and wait for a tug to come and tow him. Once the aircraft is disengaged from the cable the point man will signal the operators to rewind the tape and ready the barrier for the next engagement.
The BAK-12 arresting system has been in use for probably 50 years or so. I was a crew chief on them in Korea from 1972-1974 and we caught USAF and ROKAF F-4 Phantom IIs. Hope this helps.
The old F-101 Voodoo had the same hooks as well.
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