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ozief16 -> RE: F-16 pilot control question (10/10/2012 5:48 PM)
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Fender,
A bunch of random F-16 flight control stuff:
To pile-on to what goose is saying, the airplane is so tail heavy that in slow-speed, high AOA flt, you can be commanding max alpha (i.e. full aft stick if you want to think of it that way), but the stabs themselves are actually deflected pretty heavily down to prevent a departure. When the airplane does depart, it falls flat at zero airspeed (Ops checked that one accidentally!).
JR mentioned the Leading Edge Flaps delfecting two degrees up in an earlier post; that's just to help the airplane land. Approach speed is actually well above quit flying speed (the computer won't actually let you stall the plane, it holds a max AOA, so I'm calling it quit-flying-speed). If you look at a viper on the ground, it looks like the LE of the inboard portion of hte wing doesn't line up with the fuse...now you know why. If you were to approach at it's slowest speed, you'd actually drag the tail quite severly. So when you come in faster than a plane wants to land, it gets a bit cranky..especially in cross-winds. Look at the speedbrakes of any F-16 you see at an airshow and the outboard corners are often times ground off from guys pitching up too much on landing or during the aerobrake. I'm sure JR can tell lots of stories of blending corners on speedbrakes.
Goose also mentioned the computer scaling back the rudder inputs. A lot of guys assume if you roll into knife edge, the plane will hold it for you and that you pushing on the rudder pedals does nothing. Both are false. The jet is set up as a G commanded system (i.e the jet is trimmed for 1G, so there is no trim change from 100kts to 600+kts, because you hold the G the same (centered trim=1G)); so basically when you roll into 90 degrees of bank, the nose falls just like any plane. You can hold the nose up with a bunch of rudder...also like a 'normal' plane. The rudder is actually quite effective and it catches guys when you stick a boot-full in and slew the plane in a way they didn't think it would go. Watch a video of the T-birds and you can see them yawing the jets into formation so the wings all stay parallel, even though the jets are moving laterally.
Not at all what you asked, but cool Gee-whiz stuff. In relation to what you asked, the stabs work as tailerons at slow speed, the flaps deploy with the gear (as JR mentioned) and will still work as ailerons as well. In fact, there's a regime that you have to watch for pretty carfeully: if you encounter wake turbulence, and rock the stick back and forth rapidly to fight it, the jet assumes you don't want the flaps down and it retracts them (I guess to improve roll authority). That obviously cuts your lift when you're low/slow and guys have slammed the jets on folding gear and ventral fins and everything else. The best thing to do there is add some power and either fly straight through the wake turbulence or just go around.
I hope this helps...Goose, were you with the IN boys?
V/R
Dave
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