Off Topic: Cavalier fin/rudder

[V1670]

Watching P-51 videos (hey, gotta get my fix). Always wondered about the taller tail on some Mustangs. Read some time ago, how early D-models lost their tails due to conversion from razorback B/C to the bubble canopy and a subsequent mod was to employ the dorsal extension to the fin. Obviously, it worked well but I've always wondered why later modifications employed the taller fin. Any benefit/detiement?

[Big_Jim]

Re: Off Topic: Cavalier fin/rudder

Watching P-51 videos (hey, gotta get my fix). Always wondered about the taller tail on some Mustangs. Read some time ago, how early D-models lost their tails due to conversion from razorback B/C to the bubble canopy and a subsequent mod was to employ the dorsal extension to the fin. Obviously, it worked well but I've always wondered why later modifications employed the taller fin. Any benefit/detiement?

I will quote my brother from his research that he did for his book on Trans-Florida Aviation/Cavalier:

"The larger vertical stabilizer comes from one of three sources: North American Aviation, NACA, or Cavalier Aircraft Corporation.

All three of these are essentially the same size and shape -- 14 inches taller, adding 2.3 square feet of surface area to the vertical.

The modification originated with NACA, who modified a P-51D and P-51B (serial numbers unknown...perhaps Mr Phillips or Mr Dienst have a photo sitting somewhere that show the SN?) for high-speed flight trials. Subsequently NAA modified two of their own P-51Ds (44-13253 and 44-84900), while considering the design to improve handling at low speed on future Mustangs. NACA then modified two *more* P-51Ds (44-13257 and 44-84864) with the same tall-tail design after the war for use on thunderstorm research missions. These two NACA-modified Mustangs still fly today, the first one with Ed Lindsay and the second one with Mike Coutches.

The 1st NACA Mustang listed above (13257) was purchased in '59 by Trans-Florida Aviation, the precursor to Cavalier Aircraft Corporation. The crew at Cavalier did some poking around regarding the reasons for 13257's taller tail, and decided that the improved handling the tall tail provided was something they wanted on their modified Mustangs, too. Thus many of the Cavalier modifed/built aircraft had this tall tail, too. They made 40+ (rough number) modifications with the tall tail.

The vast majority of the tall-tailed Mustangs flying today are Cavalier aircraft. Mike Coutches "NACA 126" (44-84864) is a NACA-modified aircraft. There are a couple Mustangs flying (or in restoration to fly) which are wearing Cavalier tall-tails, but were never Cavaliers to start with. An example is Bob Jepson's "Diamondback" (45-11471).

There have also been two Mustangs which have flown with P-51H tails bolted on. The P-51H tail is different than the Cavalier tail, although they are frequently called the same thing in print (compare photos of the two and it's obvious, especially in the trim tab area). 44-73518, which was Gary Levitz' original "Precious Metal" racing Mustang had an H-model tail bolted on. Later this *same tail* was put on a *different* P-51D fuselage (identity unknown) built up as a Griffon-engined racer by Don Whittington, also named "Precious Metal."

Referencing the other half of your question, TF-51s were not originally built (or, more appropriately, modified by TEMCO) with the tall tails. This TF-51 mod originated with Cavalier who owned at least two TEMCO TF-51s and built up several of their own TF-51s using the tall tail. I am not a Mustang pilot, but given that nearly all of the TF-51s currently flying wear the tall tail, I would guess that it does actually provide better handling."

[V1670]

Re: Off Topic: Cavalier fin/rudder

Thanks Big Jim. I knew with the wealth of information on this forum I'd get an answer. What I DIDN'T know was the origins of the tall tail...I thought this was a Cavalier-originated design. I seem to remember when Whittington flew the Merlin-engine
Precious Metal in '76 that it had the tall tail and I believe the plane that Bob Love flew an aerobatic routine (was it Brassfield's?) had the tall tail as well.

Thanks again for the info. Oh yeah.....title of your brother's book? Sounds like an excellent read.

[Big_Jim]

Re: Off Topic: Cavalier fin/rudder

Thanks Big Jim. I knew with the wealth of information on this forum I'd get an answer. What I DIDN'T know was the origins of the tall tail...I thought this was a Cavalier-originated design. I seem to remember when Whittington flew the Merlin-engine
Precious Metal in '76 that it had the tall tail and I believe the plane that Bob Love flew an aerobatic routine (was it Brassfield's?) had the tall tail as well.

Thanks again for the info. Oh yeah.....title of your brother's book? Sounds like an excellent read.

Whittington's plane had an H-model tail on it. Bob Love's plane (the grey and white one that was actually owned by Jerry Brassfield) was a Cavalier coversion.

Randy's book is 90% done with 90% to go. Like many of our combined projects they seem to stretch out over MANY years.