Beyond The Sprues

Current and Finished Projects => Physical Models => Aero-space => Topic started by: Scotaidh on October 16, 2016, 10:12:08 PM

Title: XP-76 Pacific Lightning
Post by: Scotaidh on October 16, 2016, 10:12:08 PM
XP-76 Pacific Lightning
In early 1942, the USAF was worried about having unescorted bombers operating over Japan.  The heavy losses incurred by the RAF in daylight bombing missions over Europe seemed to indicate that unescorted bombers were easy pray for modern fighter aircraft.  At a time when the Japanese seemed unbeatable, un-escorted bombing missions over the Japanese home islands seemed certain suicide. 
The Doolittle raid did nothing to allay these fears.  Of the 16 aircraft employed, none returned, and even though that had been expected, no-one liked it.  The crews did mostly return to service, but only after significant delays.  The Air Force was not happy with the idea of “single-use” aircraft, and experienced air crews were simply not expendable.
The island hopping campaign was still in planning stages at this time, and no-one knew if it would be a success or a disaster.  No existing fighter aircraft had anything like the range required to escort bombers from Peal Harbor.  Naval aircraft required vulnerable carriers, which were expensive and had long build times.
Accordingly, Lockheed was asked if there were something they could do, using an off-the-shelf solution to avoid unnecessary costs.  Hibbard and Johnson, being busy with the P-38 development, handed the project off to Virgil Upton. He decided on a ‘double-Lightning’ – basically a P-38 with pilot’s nacelle lengthened and an extended wing-and-engine set-up added outboard the original engines.  The design team was confident that this configuration would yield the required range, and that the aircraft would do well using the “boom-and-zoom” tactics beginning to work out against the Japanese air force and naval aircraft. The project was designated ‘‘XP-76’’. 
Work on the ‘‘Pacific Lightning’’, as the XP-76 was officially named, progressed well, if slowly.  Wind tunnel tests had revealed a number of serious problems that needed to be resolved before the aircraft could be safely test-flown. 
Before all the problems were resolved, it became evident that the island-hopping campaign was working, and the XP-76 program was cancelled.



Title: Re: XP-76 Pacific Lightning
Post by: Tophe on October 16, 2016, 11:42:49 PM
Wonderful! I knew this great model of yours but not the 3-view with it, genius! :-* :-* :-* :-*
Title: Re: XP-76 Pacific Lightning
Post by: GTX_Admin on October 17, 2016, 03:03:42 AM
Nice entry.
Title: Re: XP-76 Pacific Lightning
Post by: apophenia on October 17, 2016, 03:31:25 AM
Great stuff. I'd love to see some in-progress shots of this beauty  :-*
Title: Re: XP-76 Pacific Lightning
Post by: The Big Gimper on October 17, 2016, 06:29:27 AM
Yowzers!!! As noted above, how did you build this beauty?  :)
Title: Re: XP-76 Pacific Lightning
Post by: finsrin on October 17, 2016, 08:52:31 AM
Another "Yowzers",,,,   Have in-progress shots as mentioned above?
Extended nose is proper to keep XP-76 in balance - good touch. :)
Title: Re: XP-76 Pacific Lightning
Post by: Camthalion on October 17, 2016, 11:57:32 AM
Very cool.  Great work.
Title: Re: XP-76 Pacific Lightning
Post by: elmayerle on October 17, 2016, 12:15:13 PM
Beautiful piece of work, I love the small little touches that abound.   I have to wonder if this is where the longer center pod of the "Lightning Swordfish" came from.
Title: Re: XP-76 Pacific Lightning
Post by: Brian da Basher on October 19, 2016, 01:41:03 AM
Now that's a powerful introduction, in more ways than one!

I have to tip my hat to your creativity! This configuration looks like it almost could've been!

Most excellent!

Brian da Basher
Title: Re: XP-76 Pacific Lightning
Post by: taiidantomcat on October 19, 2016, 01:55:00 AM
 :-*

just too beautiful!

Title: Re: XP-76 Pacific Lightning
Post by: FAAMAN on October 19, 2016, 12:40:46 PM
 :-* :-* :-* seriously cool work!!!  8) 8) 8)
Title: Re: XP-76 Pacific Lightning
Post by: CiTrus90 on October 19, 2016, 08:11:54 PM
Awsome work!
Title: Re: XP-76 Pacific Lightning
Post by: Scotaidh on October 20, 2016, 04:22:23 AM
Sorry for the delay in getting back to you about the build-photos.  I had to locate the files.  :)

You've seen the Concept Drawing. (http://s45.photobucket.com/user/Scotaidh/media/Models/P-76%20Pacific%20Lightning/001%20Lockheed%20P-76%20Pacific%20Lightning%20Prototy_zpsa4rrmph5.png.html?sort=3&o=0)

I generally do one of those for my builds, to sort of see what it should look like.

I got two Revell 1/48 Lightning kits, and set to combine them.  I cut off the outer wing just outboard of the engine.  That didn't give me enough clearance between the props, so I had to add in sections (http://s45.photobucket.com/user/Scotaidh/media/Models/P-76%20Pacific%20Lightning/006P-76Construction.jpg.html?sort=3&o=10) of what I had just removed!  :(  I reinforced the joints by adding wing-spars.  :)  As you can see, I had to extend the inner wing chord to have a straight trailing edge to my wing.  I used a lot of putty - both Squadron Green and White in alternating layers - to make it look believable. 

I then had wing thickness issues (http://s45.photobucket.com/user/Scotaidh/media/Models/P-76%20Pacific%20Lightning/ConstructionP-76008.jpg.html?sort=3&o=13) .... grrr.  Another issue that benched the project for a year was gathering the courage to cut the inner two empennages to extend them back - because of the leading edge wing sweep, of course the outer booms were 'longer' than the inner two!  :(

Achieving the proper wing dihedral was also a project. (http://s45.photobucket.com/user/Scotaidh/media/Models/P-76%20Pacific%20Lightning/ConstructionP-76007.jpg.html?sort=3&o=15)

This build was plagued with issues that seemed to always surprize me - just goes to show I'm not the planner I thought I was!  :)  I see I've used my four pictures for this post, so I will take a break and post more later.

Thanks for your interest!  :)
Title: Re: XP-76 Pacific Lightning
Post by: Scotaidh on October 21, 2016, 05:08:58 AM
Build Part II
The extended nose (http://s45.photobucket.com/user/Scotaidh/media/Models/P-76%20Pacific%20Lightning/XP-76%20Construction%20014_zpsciulvcar.jpg.html?sort=3&o=10) was for two reasons - it didn't look right as the original length, and I needed room for weights.  I ended up filling the engine nacelles with weights also, just to keep this from tail-sitting.

The double main undercarriage was no problem - I just used the extra legs from the other kit.  I did have to trip the pivot pins, and add some strengthening, which, fortunately, is hard to see.  I then had to open up the gear doors.  I used a razor saw to extend the doors up to the wings, and made them double doors. (http://s45.photobucket.com/user/Scotaidh/media/Models/P-76%20Pacific%20Lightning/XP-76%20Construction%20051_zpsehsgqxtu.jpg.html?sort=3&o=3)

Because the radiator housings were simply empty shapes, I filled them black sponge-foam.  Because the USAAF had no real policy on prototype markings, I kinda invented my own (http://s45.photobucket.com/user/Scotaidh/media/Models/P-76%20Pacific%20Lightning/XP-76%20Construction%20038_zpsujq7q4be.jpg.html?sort=3&o=10) - a white P on the vertical stabilizers, two facing each side.

I also built a landing light (http://s45.photobucket.com/user/Scotaidh/media/Models/P-76%20Pacific%20Lightning/XP-76%20Construction%20043_zpsu4ra5reg.jpg.html?sort=3&o=9) to fill the otherwise
empty hole in the wing.  'Course, then I couldn't use the clear plastic insert, so I just filled in the hole with clear cement.

And that's my four pictures for this installment.  :)  Not much more to tell - just some matte varnish over-all to finish, and this project which had taken the best part of 5 years to complete ... was.  :)

Title: Re: XP-76 Pacific Lightning
Post by: Tophe on October 23, 2016, 05:17:50 PM
The double main undercarriage
Thanks for pointing out this detail! (I am ashamed I had not noticed the main undercarriage was double... ??? ).
To apologize, I clap my hands again (double!) and I add a version with fixed landing gear, together with a floatplane one, thanks again!
Title: Re: XP-76 Pacific Lightning
Post by: Brian da Basher on October 23, 2016, 05:35:12 PM
My, what lovely spats you have there, mon ami!

So sleek, so streamlined...

 :-* :-* :-*

Brian da Basher
Title: Re: XP-76 Pacific Lightning
Post by: Tophe on October 23, 2016, 09:37:57 PM
Brian, did you ever see an airplane with 5 spats? ??? ;) Thanks Scotaidh! :D