Warbird Information Exchange

The TEMCO TF-51 did not have the taller vertical stabilizer...the Cavalier TF-51s pioneered the idea, and recent restorations/modifications by various warbird shops have copied the idea.

Thanks, I will get in touch with Lee Lauderback.

I actually did e-mail Courtesy, but to my surprise, no replay...

In what way would the raised fin affect aerobatic flying, other than increased rudder authority?

Anyhow, I have no need for a full TF, a skeleton conversion will be just fine…

The big fin only affects cruise stability, especially noticable for the large canopy TF-51 airframes. It has no effect on aerobatic ability or rudder authority.
VL

Hey randy
I have a photo of a Tenn. ANG TF-51 with the small tail. Remind me to scan and email that to you aftr the first of the year.
The extra vertical fin area is supposed to help a little with high power settings/ low airspeeds. It might have helped on the gunnery range,too.(guess.)
The only difference I could tell between the high tailed TF(Crazy Horse) and a stock P-51D was on takeoff at the point of rotation, the tail would wiggle slightly from the torque. After that I noticed the airplane had leaped to 135 mph and the gear was still down. Last time I ever thought about the vertical fin.
Lee would be the best to explain as he loves to have students do loops with power while in the stall buffet. He also demonstrated to me a loop where at the top we were indicating 35 kts! (half the stall speed) He's nuts!

I find the TF-51 to be rather ugly compared to the single seat variety (I say comparativley because I love them all anyway). There have been a number of partial conversions done over the years: ie: a stick and reduced instrumentation in a back seat without the extended canopy of the full TF. Very discrete and lets the back seat rider control the aircraft.

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I've heard mixed reactions from pilots who have flown both. A couple of the Cavalier test pilots said they noticed no tangible difference between the handling performance while maneuvering and on takeoff/landing.

Chuck Lyford, who flew the Cavalier in combat in El Salvador, told me that the tall tail definitely enhanced the stability of the Mustang when strafing. Since he's one of the few people who has actually employed a tall tail Mustang in combat (I'm guessing there are a few in Bolivia and Indonesia, too), as well as having significant amounts of high performance acro and racing time in a stock Mustang, I'm inclined to believe his input on the matter.



If you're not demanding anything from the wing, it doesn't matter what the indicated airspeed is. Stall is an angle of attack, not a fixed airspeed. At the top of a loop, you're not pulling on the stick too hard or commanding any nose up authority, so you can get as slow as you please.

In the F-15E we have an advanced handling exercise that we do which consists of pulling the nose up to about 70 degrees nose high until the airspeed gets to about 30 knots (the Vso is something in the neighborhood of 150 knots in the Strike Eagle). Then, we simply release the backpressure on the stick and push forward ever so slightly to maintain about .8 G. The jet simply floats over the top of the arc (the pitch angle decreases, naturally, because of the gentle forward stick pressure), maintains the slow airspeed, and the jet doesn't even so much as shudder or burble. The nose ends up about 45 degrees nose low on the other side with the airspeed increasing.

Yes this is some of what Lee teaches in his advanced curriculum. He calls this "un-G-ing" the airplane. The TF stalls at between 72 and 76 kt.s depending on what youre doing, flaps and fuel onboard and how smooth the air is. That assumes a nose up wings level, and pulling one G. The stall speed lowers as the amount of weight being tasked the wing is lowered. In other words the wing has a lower stall speed at '0' g's than at 1 or more G's.
His point of teaching this is so if a newcomer like me honks back on the stick and pulls the airplane into an accelerated stall, or too abrupt pull up, you can avoid the stall by un-G-ing the airplane. There are limitations of course, not the least being your altitude above the ground.
There is another part of the envelope I have experimented with in small aircraft and gliders where you are far below the stall speed but the aircraft is continuing in motion(momentum) until the aircraft reaches back near the speeds which the wing is creating lift and acting like a wing(if you keep everything coordinated.). Is this what you guys are doing in the F-15?