F-16 Tailhook Procedures

Hey there guys!

I know the Viper will never land on a carrier, but having a tailhook can still be useful ! I'm fairly familiar with the Navy's version of tailhooks having grown up near Miramar, but I don't know much about the Air Force tailhooks other than they catch a wire that's stretched across the runway so the pilot doesn't have to go off-roading .

So how does the Viper's tailhook work? How do you deploy it? Is it a button you push or a handle you pull or a switch you flip? How do you return it to the normal stowed position? Is it another button etc, or is it the old "let the crewdawgs push it back up by brute strength" system ?

If it's not hydraulically operated, what holds it up while in flight? When do you use it? Is there a specific set of criteria for when to use the tailhook, or is it just when the brakes go out? I've seen some discussion on this site about the tailhook being used as a holdback for engine runs etc., but is this standard proceedure? Last, but certainly not least, how much of a pain in the posterior for the maintenance guys? Is there anything particularly annoying about maintaining the tailhook and its supporting systems?

I know this is a lot of questions to ask in one post, but I have no clue whatsoever as to the answers and the next airshow ain't 'till March when the T-Birds are scheduled to do a show at Indian Springs, so I figured I'd ask around here rather than waiting .

Thanks in advance!

It is blown down by nit pressure and we reset it through brute force. It breaks a little bolt when it is really used but not when we drop it on a chock to op check it. You can also drop the hook by pulling the pin and popping the latch manually. Then it just drops down with a little bounce. The nit bottles blow it down and hold it there for catching the cable. The hook safety pin always has to go in left to right as you see in the pics you posted. The switch is a simple two position switch not far from the landing gear handle.

EriktheF-16462, thanks for the quick answer! This one had me stumped. Just curious, why does the pin always have to go in left to right? Oh yeah, one other thing, has anyone ever seen a tailhook deployed by accident either on the ground or in the air?

Pin only works that way but can be inserted from the wrong side and I have never seen one deploy by accident. Shear bolt can be seen in the second picture. It is there to keep the hook in line with the jet but it easily breaks by design because no one ever catches the cable perfectly.

If the pin is inserted in reverse, the hook can be inadvertly if the hook isn't all the way though the latch assembley. The actuator in the aircraft that operates the hook compresses rather than extend to deploy the hook for use. 3000PSI is available to keep the hook on the ground for a successfull hook engagement. Once the aircrew puts the switch in the up position the spring on the actuator will make the hook come off the ground about 4 inches. The hook is positioned in the stowed position by the ground crew (usually crew chiefs). The bottle that stores the air pressure is located in the engine bay, and the gauge to read and service it, is located in the nose wheel well.

The shear bolt talked about is located on the forward portion of the tail hookjust forward of the left right pivot point, aft of the up down pivot point.

Thanks for the great info guys! I knew if I asked for details on this system I'd get them here! I'm a bit confused about the actuator, though. How does it work by compression? Is it buried somewhere in the jet, designed to pull the front up rather than push the back down? I think I'm going to have to check for the gague in the wheel well the next time I go to an airshow! Great info about the shear bolt, I'd never have thought about needing one like that, but this ain't a Navy jet so I'd imagine you don't want to stress the airframe any more than necessary. I'm glad the hook comes up those four inches by itself - it would really suck to have to go out and try to stow it at the end of the runway!

Can't speak from a maintenance perspective, but to answer your employment questions, I'll drop the hook anytime it's apparent that I will or am experiencing difficulties stopping the aircraft in the runway remaining. There are certain landing gear malfunctions that call for an approach end cable arrestment, and landing gear up (not on a centerline tank though) is an option with the hook. I've dropped the hook once, didn't engage though. Had an ANTISKID caution light early into takeoff roll, early enough to abort for petty caution lights. I think I aborted at 80 knots on a 10,000 foot runway. Brakes didn't work, so I dropped the hook. Took me over a mile and a little more than a minute to get stopped, I reverted to manual braking (take HAL out of the loop) but not before I'd dropped the hook. From the way tower was yelling, I'm guessing it created quite the spark show.

STBYGAIN, thanks for the info! I can only imagine how big a spark show you created! By the way, was the fire department called out for this? I've never heard of taking the computer out of the loop for braking and I thought you needed the computer to be able to actuate the brakes. I hadn't thought of it, but using the hook with a gear up landing makes perfect sense - no wheels = no brakes = use the hook! Can anyone expand on what would require an approach end cable arrestmant?
Thanks again guys and please keep it coming!

STBYGAIN wrote: Had an ANTISKID caution light early into takeoff roll, early enough to abort for petty caution lights. I think I aborted at 80 knots on a 10,000 foot runway. Brakes didn't work, so I dropped the hook. Took me over a mile and a little more than a minute to get stopped, I reverted to manual braking (take HAL out of the loop) but not before I'd dropped the hook. From the way tower was yelling, I'm guessing it created quite the spark show.

STBYGAIN....would momentarily cycling the Park Brake switch a few times help ya get slowed down in that situation? Seems like I remember the checklist suggesting that but only as a last resort. Then again it's been so long since I looked at a Viper checklist I could be wrong on that.

Parking brake might do the trick but you run a good chance of shredding your tires at any speed aboved taxi speed. I'd take my chances with the cable first. Parrothead: Yes, fire department responded, not by my request though. As far as approach end arrestments go, there are some configurations where the checklists direct it, examples are no nose gear, no main gear but good nose gear, no gear at all, and faulty indications. Fuel also plays into what you want to do with gear problems. There are some unlandable configurations though.

Thanks for all that info STBYGAIN! I'd hate to be in the seat with an "unlandable" configuration ! From what I see, it looks like you use the hook any time you can't stop or you can't control where the jet will go once it's on the ground. You got me curious again - what's considered an unlandable configuration?

Alright maintainers, what's the worst part of dealing with the tailhook? It has to be a pain being on the bottom of the jet, right between the ventrals! I had to lie down on my back to get those pics and I'd think working on it would have to be even worse!

I don't ever remember thinking it was in the way. We have to drop it down on occasion, like when we R&I engines but it is really easy so, so what. Other than that we just crawl around under the jet which in itself is a real pain in the knees.

Glad to hear it's not as bad as I thought! Thanks for the info!

The second picture shows an arm coming out from the airframe, that arm is pulled aft, the actuator is fixed mounted in that square panel above the hook under the engine. The actuator compresses pulling the arm aft, thus extending the tail hook. When deselected the actuator extends from the spring on the actuator. Sort of like a large down lock actuator..

I think I got it now ! Great description!