avatar_sandiego89

P-38, jet powered, project BUNSEN- finished

Started by sandiego89, March 14, 2014, 02:34:10 PM

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sandiego89

In 1943 a secret delegation brought several jet engines from the U.K. to the United States to show US manufactures the latest turbojets.  Bell and G.E. were selected to investigate a new fighter to demonstrate this jet technology.  

As a secret side project codenamed BUNSEN, several manufacturers were asked to see what existing fighters could be adapted for jet power.  The specification called for the minimal amount of modifications possible with the hope that overseas depots could make the switch from piston to jet power.  

Lockheed quickly jumped on board with a P-38 based design.....

The Kit: 1/72 Matchbox


Do I get extra credit for using the very tired and infamous tri-colored Matchbox kit?  ;D   Yes stash clean out time



No need for radiators...


Or the supercharger.....



supercharger and radiators blocked off with sheet styrene



Now for the donor engines, Jumo nacelles from a 1/48 Lindburg me-262

Off with the Allisons.  On with twin Wellands.


Dave "Sandiego89"
Chesapeake, Virginia, USA

kerick

Add a tail to the center pod and make the engines wing mounted. I know, that's not your plan. I couldn't stop myself.
" Somewhere, between half true, and completely crazy, is a rainbow of nice colours "
Tophe the Wise

NARSES2

Now I once considered a jet powered P-38, when I got back into the hobby I think, but the engine layout left me flummoxed. Therefore I'm very interested to see how you handle it  :thumbsup:
Do not condemn the judgement of another because it differs from your own. You may both be wrong.

sandiego89

Quote from: NARSES2 on March 15, 2014, 03:16:05 AM
Now I once considered a jet powered P-38, when I got back into the hobby I think, but the engine layout left me flummoxed. Therefore I'm very interested to see how you handle it  :thumbsup:

Think Hawker Seahawk, twin engines with bifrucated jet pipes.
Dave "Sandiego89"
Chesapeake, Virginia, USA

Captain Canada

This is gonna be good ! Love watching people hack and chop a kit  :thumbsup:

Love them old Matchbox kits. What great times as a kid.....

:cheers:
CANADA KICKS arse !!!!

Long Live the Commonwealth !!!
Vive les Canadiens !
Where's my beer ?

Dizzyfugu

They are STILL good. Many people quibble about lack of details, and , O.K., some are REALLY horrible (the Alpha Jet is one of the worst kits I know - even though the parts actually fit together!). But they are solid renditions, fit is good most of the times, and some are well-detailed - you get very good value for the money.

Besides, I am also curious how this turns out here, too - curious about the landing gear arrangement, that's one thing that's easily overlooked in the joy of cutting and modifications...  :thumbsup:

sandiego89

Quote from: Dizzyfugu on March 15, 2014, 05:55:02 AM
They are STILL good. Many people quibble about lack of details, and , O.K., some are REALLY horrible (the Alpha Jet is one of the worst kits I know - even though the parts actually fit together!). But they are solid renditions, fit is good most of the times, and some are well-detailed - you get very good value for the money.

Besides, I am also curious how this turns out here, too - curious about the landing gear arrangement, that's one thing that's easily overlooked in the joy of cutting and modifications...  :thumbsup:

Thanks guys, yes I too like most matchbox kits also, they are simple and affordable, and pretty good for their age.  I tend to get more joy out of a simple build without fussy bits and expensive aftermarket stuff- like Captain says- takes you back to the good'ole kid days. 

Dizzy, I'm going AROUND the landing gear. Pictures tonight if all goes well.

-Dave
Dave "Sandiego89"
Chesapeake, Virginia, USA

Tophe

Interesting project! I plan to draw the final result in my gallery of fantasy Lightnings. :thumbsup:
[the word "realistic" hurts my heart...]

NARSES2

Quote from: sandiego89 on March 15, 2014, 05:42:11 AM
Quote from: NARSES2 on March 15, 2014, 03:16:05 AM
Now I once considered a jet powered P-38, when I got back into the hobby I think, but the engine layout left me flummoxed. Therefore I'm very interested to see how you handle it  :thumbsup:

Think Hawker Seahawk, twin engines with bifrucated jet pipes.

Interesting  :mellow: Never occurred to me at all  :bow:
Do not condemn the judgement of another because it differs from your own. You may both be wrong.

sandiego89

#9
Thanks guys, commencing work on the engines. This will have the jet exhaust going around each side of the tail boom, like the SeaHawk. The project BUNSEN specification called for minimal amount of modifications with the switch to jet power.  So essentially a fire wall forward swap out.

A Welland engine weighs around ~850 pounds, an Allison is around ~1,390 pounds (plus the propellor weighing? and the superchargers and radiators.  The steel exhaust pipes will cancel some of the weight savings.  A 1/48 scale Jumo pod is about right to house the diameter of a 1/72 Welland.  

Thin aluminum pipe from the hardware store.  Carefully bent and cut off with a dremel.




Side view, starboard tail boom.  Installed the rear part of the nacelle.  Installed a heat shield between the exhaust and the tail boom, will likely extend it further.  Original test fit of jet pipes- too far forward.



After some measurements, needed to move the pipes further aft. this was still in the forward postion, but shows the layout.






Moved the pipes aft a bit.  The Wellands are mounted very far far forward and gives enough room for the bfirucated jet pipes. Based on a SeaHawk cutaway, the pipes were a pretty compact unit, but a plumbers nightmare. 



Stern view, showing the twin exhaust.


Rough lay up.  





 
Dave "Sandiego89"
Chesapeake, Virginia, USA

NARSES2

Do not condemn the judgement of another because it differs from your own. You may both be wrong.

Tophe

[the word "realistic" hurts my heart...]

kerick

Might have to install a heat shield on the underside of the wing and cut out a portion of the flaps.
" Somewhere, between half true, and completely crazy, is a rainbow of nice colours "
Tophe the Wise

sandiego89

Quote from: kerick on March 17, 2014, 04:50:02 PM
Might have to install a heat shield on the underside of the wing and cut out a portion of the flaps.

Thanks.Yes I may. Wings may be ok, but flap is close. No work on this for a few days as I am in Atlanta for work for a few days.
Dave "Sandiego89"
Chesapeake, Virginia, USA

Sauragnmon

Alright, this is interesting... I have to say, the idea makes me intrigued to do my own version at some point... though I'd probably consider Yak-28 style exhausts on the concept, but still, looking very interesting.
Putty-fu, Scratch-jutsu and Bash-chi, the sacred martial arts of the What-If. Mastering them, is Ancient Chinese Secret.

Just your friendly neighbourhood Mad Scientist and Ship-whiffer.

Overkill? Nah, it's Insurance.  So are the 20" guns.