Xp-72 Finished - Monogram/koster Kit

[elmayerle]

Gorgeous work!!!  It should definitely turn some heads among the "experts".

Tell me, how is the Koster kit to work with?  I'm thinking of getting one to cross with a P-47N wing to do a P-72B.

Another thought:  It appears that contra-props on the R4360 never were that successful given the substitutions used on the second XP-72 and on the XB-35 (I'm thinking there must have been a limitation of the P&W gearbox that prevented sufficient rebustness), so, instead of settling for a large four-bladed prop, might the USAAF instead contract with Rotol for some suitable 5-bladed props to fit R4360s?

[braincells37]

Tell me, how is the Koster kit to work with?  I'm thinking of getting one to cross with a P-47N wing to do a P-72B.

The Koster kit was almost like using the Monogram fuselage. Save for a few soft edges at the wing root (requiring a bit of extra putty) it was great. The only thing I did was add a brass spar to the Monogram wing tabs. Probably not necessary but made the wing fuselage join a bit more solid. I thought about the 5 blade prop for a  bit, but I just liked the looks of all those blades up front. Bill Koster engineers some really fine vac kits. I've done a number of them over the years and found them to be a joy to assemble.
Terry    

[kitnut617]

Another thought:  It appears that contra-props on the R4360 never were that successful given the substitutions used on the second XP-72 and on the XB-35 (I'm thinking there must have been a limitation of the P&W gearbox that prevented sufficient rebustness),

Hi Evan,

Interesting observation about the gearbox problems the R-4360 had, but I had thought it was only on the XB-35 where this happened.  I had thought that this was because of the different gearbox the XB-35 had, they being on the end of a long drive shaft and not directly attached to the engine.

Your note about the second XP-72 prototype is the first I've come across that it had problems.  Did the Douglas XTB2-D-1 have the same issues as this had the same engine and props I think.  Come to think of it though, I think it had two four blade contra-props.

Robert

[John Howling Mouse]

Beautiful, especially the rich, dynamic colors of the scheme.

What a head-turner this would be at any gathering of modelers!

 

[Supertom]

Most cool - any chance we could see the undersides?

[Sisko]

Very cool, Love it!!!!!!!

[Mike Wren]

gorgeous!    

[elmayerle]

Another thought:  It appears that contra-props on the R4360 never were that successful given the substitutions used on the second XP-72 and on the XB-35 (I'm thinking there must have been a limitation of the P&W gearbox that prevented sufficient rebustness),

Hi Evan,

Interesting observation about the gearbox problems the R-4360 had, but I had thought it was only on the XB-35 where this happened.  I had thought that this was because of the different gearbox the XB-35 had, they being on the end of a long drive shaft and not directly attached to the engine.

Your note about the second XP-72 prototype is the first I've come across that it had problems.  Did the Douglas XTB2-D-1 have the same issues as this had the same engine and props I think.  Come to think of it though, I think it had two four blade contra-props.

Robert

I may be in error, but I do remember pictures of at least one of the XP-72s flying with a four-bladed prop.  Ah, a bit of excavating of the reference books and I find that the first XP-72 flew with a R4360-13 and a four-bladed prop while the second flew with a R4360-19 and a six-bladed contra-prop.  Possibly the correct engine/prop combination wasn't ready in time for the first prototype.  I do seem to have been a bit in error then.  OTOH, if R4360-19s with the contraprop gearbox were delayed in production, other possibilites do present themselves....

[kitnut617]

I may be in error, but I do remember pictures of at least one of the XP-72s flying with a four-bladed prop.  Ah, a bit of excavating of the reference books and I find that the first XP-72 flew with a R4360-13 and a four-bladed prop while the second flew with a R4360-19 and a six-bladed contra-prop.  Possibly the correct engine/prop combination wasn't ready in time for the first prototype.  I do seem to have been a bit in error then.  OTOH, if R4360-19s with the contraprop gearbox were delayed in production, other possibilites do present themselves....

In the 'Complete Book of Fighters' (Green/Swanborough) there's a photo of both prototypes.

I had bought an early Model Alliance kit of the XP-72 in 1/72 which had the four blade prop and after seeing the contra-prop version in the book, changed the model to this version, I found that the old Modelcraft/Novo/Revell Shackleton kit's spinners matched the kit's spinner of the XP-72 so I used one set of them to do it.
The latest reincarnation of the kit by CMK has the contra-prop BTW.

Of interest, the photo of the second prototype with the contra-prop is taken from about 3/4 rear and not to take anything away from BrainCells brilliant model there's an item of detail which I noticed while I studied the pics.  You can see the scissor link of the main undercarriage leg on the left side of the starboard leg.  As we are looking at this from the rear this can only mean that the scissor link had been turned 90 degrees towards the fuselage because if the scissor link was in the usual P-47 position it wouldn't be visiable.

A close inspection under a magnifying glass of the photo of the first prototype reveals it was the same for this aircraft too.

[braincells37]

Of interest, the photo of the second prototype with the contra-prop is taken from about 3/4 rear and not to take anything away from BrainCells brilliant model there's an item of detail which I noticed while I studied the pics.  You can see the scissor link of the main undercarriage leg on the left side of the starboard leg.  As we are looking at this from the rear this can only mean that the scissor link had been turned 90 degrees towards the fuselage because if the scissor link was in the usual P-47 position it wouldn't be visiable. A close inspection under a magnifying glass of the photo of the first prototype reveals it was the same for this aircraft too.

Shhhhh. (Don't tell ANYBODY else). I used the kit gear OOB, without changes. Didn't want to hassle with it (mods to gear well, doors, struts, etc.). At least I got the dark blue right!
Terry      

[cthulhu77]

My oh my...how my head is spinning.

  Fantastic build. Nuff said.

[Eddie M.]

Beautiful aircraft. An all around visually striking subject. Outstanding work! B)
  Eddie