Rolls Royce PV Fighter and FTB

[kitnut617]

These were built after I had seen the FTB conversion on Unicrafts website and I bought one.  I'd not seen or heard anything about this aircraft but as I'm an Air-Britain member I put the question to the membership about them.  One member is David Birch who is also the official RR Historian and after contacting him he suggested I buy his book on the RR Mustangs.  The majority of this book is about how RR converted the Mustang to the Merlin (highly recommended BTW and can be bought through the RR Heritage Trust) but there is a chapter on these Private Venture Fighter and Flying Test Bed aircraft.

http://groups.msn.com/TheWhatifandoddballm...to&PhotoID=2101


Cheers,  Robert

I tried to post one but I think the photos are too big

[Shasper]

Kinda reminds me of the Fisher Eagle.


Shas B)

[kitnut617]

Yes it does, I have a model of the XP-75 only it must be a later development as it has a clear bubble canopy insteadt of the greenhouse one.

Cheers,  Robert

[Tophe]

Thanks for this very interesting topic...  I did not know at all this FTB with a different tail.
Question: when you say "the tail surfaces were undersize by about 60%": do you mean dimensions or areas? 160% dimensions would mean 256% area, 160% area would mean 126% dimensions... (I'd be glad to draw a Mustang FTB with increased tail still looking like a Mustang tail, that is the reason of my question). If you have not the answer, I may either:
- draw a 1/72 FTB with a 1/48 tail (150% dimensions, 225% area) - we are modellers... or
- try measuring the fin areas on your profile phorograph at the same distance of both models.
Thanks again!

[kitnut617]

Hi Tophe,

The book says 60% area.  Rolls Royce was issued a Tempest tail which David Birch (the author of the book) has told me would have been from the standard assembly joint backwards, tail wheel and all.  He told me that the rudder hinge line would have been in the same place, which put the assembly joint of the Tempest tail right through where the Mustangs tail wheel would be.  The fuselage of the FTB was a new concoction designed by RR so removing the Mustang tail wheel wouldn't have been a problem.  The Crecy two stroke engine was projected to put out about 5000 hp, so the two four bladed contra prop was my idea. The PV had two three bladed contra props for the Griffon engine that would have been installed.   Remember this aircraft came about because RR couldn't easily place the Griffon on the front of the Mustang.  If you have a look at some of the Reno racers which are using Griffons from Shackletons, you'll see that they have to place the engine almost at the pilot's feet.  This removes the forward fuel tank and other bit and pieces usually found in a standard Mustang.

Cheers,  Robert

[wolfik]

wow! the FTB with the tail looks awesome.....
will convert my to this configuration too...
any bigger picture?from above?
regards!

[kitnut617]

Check my link again, I've added some more pics.  Talking of which, how did those pics appear in my posts.  Thanks to whoever did that.

Cheers,  Robert

Edit:  My first go at these was the brown and green one.  RR were issued three Mustang Mk.1's so they could use the wings,  Unicraft suggests using the Revell P-51B as the base kit.  There's some pros and cons to this. Pros are that the wings are the correct shape, (no leading edge root fillet) the con is it's the wrong radiator duct.  Also while building the conversion I wanted to detail the cockpit a bit.  I found that the conversions forward fuselage was too short, by about 8mm.  I had estimated that a 20mm cannon was around 6 feet long and where the end of the gun barrel is postioned in the spinner, it would put the breech of the gun right in the pilot's n#&s.  I contacted David Birch to ask what the overall dimension were and he told me that the original 1/10 scale wind tunnel model still existed and he knew who had it.  The up-shot was that David asked this fellow to measure the model he had and that's how I found out the kit is 8mm short.  Once I extended the fuselage forward of the wing, things fell into place.  Another thing with the conversion is the spinner is to pointy, it's actually much more like what you find on the Frog/Novo Shackleton, and that's what I used in the end a contra prop from a Shackleton with the blades shortened to 11 foot diameter.

When I got another conversion to make the silver one, I decided to use the Italeri Mustang Mk.1.  There's pros and cons to this way too only it's the other way around to the Revell kit.  Wrong wings but right rad duct.  On this one I used a spare spinner I had left over from my XP-72 model (contra-prop version and very similar to the Shack's spinners) and then used a set of props from a Magna Models DH Hornet (white metal)  I did a number of other things differently to how the kit conversion says do, but that's another very long story.

Cheers.

[elmayerle]

*chuckle* Might be fun to do an operational one with Mustang I wings with the four cannon.

[Tophe]

Hi Tophe,
The book says 60% area.

Thanks for this useful detail. I am going to dream and draw...
Thanks again...

EDIT: this is done at http://www.whatifmodelers.com/forum//index...20&#entry152859

[SimonR]

What does the abbreviation FTB stand for?

[Tophe]

Flying Test Bed, I think.

[kitnut617]

Flying Test Bed, I think.

That is correct, Flying Test Bed and Private Venture.

Sorry about that, I forget that people are not familiar with some abbreviations and I get carried away with myself.

Cheers,  Robert