Airacobra, Kingcobra, and Airabonita Ideas and Inspirations

[elmayerle]

Hmm, I'd love to see the frontal view of that one.  The profile definitely looks interesting.

[dy031101]

I did try to keep the nose and cockpit to the same scale as the engine when I pasted together the sideview, but the result might still look rather like the Piaggio P.119 (3-view here) frontally.

Actually that's where the chin intake idea (as suggested by jcf) comes from.  The control surfaces of the XFL-1 were scaled up.

[elmayerle]

Ah, I see.  I wonder if a newer wing derived from that of the P-63 would help performance?  For more fun, the wings and tail surfaces of the L39-2 but with retracting gear.

[jcf]

Skip the R-2800 and use the 21-cylinder R-2300 Triple Wasp Jr.* 
It's 44" diameter would mean that the airframe would'nt be as porky.

Anyhow effectively cooling a buried radial is not any easier than cooling an air-cooled V-12,
and there is no reason that Lawrance type air-cooled cylinder design (the basis of all Wright and P&W
air-cooled radials) could not be successfully applied to the V-12 format. Wright built the air-cooled
V-1460 and V-1560 engines in the late-twenties and there is actually no technological reason that
development of high-powered air-cooled V engines couldn't have continued, if so desired.

 

* of course such an engine never existed in the 'real-world', but when did that ever stop us? 

[Weaver]

An X or H engine would be a good compact choice too. Sabre-Cobra anyone?

Some of the Fairey designs that eventually lead to the Gannet had two Merlins, one behind the cockpit and one under it, driving co-axial counter-rotating props. It struck me that the design might be compact enough for a fighter (as opposed to an attack aircraft) if the engines were smaller capacity flat-12s, i.e. total engine power is about 2 x 1000 hp as per a conventional late-war fighter but you have the advantages of two engines, smaller prop diameter etc....

[dy031101]

R-2800-powered FL-1 with P-63-derived wings and four-blade propeller.

[elmayerle]

Anyhow effectively cooling a buried radial is not any easier than cooling an air-cooled V-12,
and there is no reason that Lawrance type air-cooled cylinder design (the basis of all Wright and P&W
air-cooled radials) could not be successfully applied to the V-12 format. Wright built the air-cooled
V-1460 and V-1560 engines in the late-twenties and there is actually no technological reason that
development of high-powered air-cooled V engines couldn't have continued, if so desired.

Well, actually, cooling a long row of cylinders gets to be a bit more of a chore than cooling a radial, especially when you get to the cylinders farthest from where the cooling air enters (one reason Lycoming's IO720 isn't/wasn't as popular as it might have been, that fourth row of two cylinders needed extra cooling scoops since air coming in the front of the cowling really wasn't reaching them, even with good baffling directing the flow).  The same applies to multiple rows in a V or IV configuration.

[jcf]

Anyhow effectively cooling a buried radial is not any easier than cooling an air-cooled V-12,
and there is no reason that Lawrance type air-cooled cylinder design (the basis of all Wright and P&W
air-cooled radials) could not be successfully applied to the V-12 format. Wright built the air-cooled
V-1460 and V-1560 engines in the late-twenties and there is actually no technological reason that
development of high-powered air-cooled V engines couldn't have continued, if so desired.

Well, actually, cooling a long row of cylinders gets to be a bit more of a chore than cooling a radial, especially when you get to the cylinders farthest from where the cooling air enters (one reason Lycoming's IO720 isn't/wasn't as popular as it might have been, that fourth row of two cylinders needed extra cooling scoops since air coming in the front of the cowling really wasn't reaching them, even with good baffling directing the flow).  The same applies to multiple rows in a V or IV configuration.

Operative term is buried i.e. like the Piaggio P.119, and I'm quite familiar with the ins & outs of air-cooled
engines in their various permutations, in the real world. The Armstrong-Siddeley inline cylinder radials had
cooling problems, thus the big scoop arrangement on the Whitley testbed for the Deerhound. The air was
brought in behind the spinner and then ducted over the cylinder banks from the rear, exiting at the
forward end of the cowling.
The Gypsy-12 powered D.H. 91 and D.H.92 used a similar reverse-flow ram-air cooling system.

So as we are talking about fantasy aircraft, why not a buried air-cooled V-12 naval fighter with reverse-flow
ram-air cooling? No one has said it would have to be a successful design.
 

[elmayerle]

Actually, I'd probably use scoops feeding air in between the cylinders from both from and back, further pressuring that area and getting the cooling flow across the cylinder fins and out through exit louvers or flaps (I like louvers myself, but flaps might give you a smidgeon of thrust) on each side of the aircraft (at least that way you don't have hot air from both sides meeting in the middle, as reversing this concept would do, and going out, depending on V or IV configuration, louvers in the top or bottom of the fuselage).  I can certainly see where they'd try it to get a more streamlined air-cooled fighter; how successful it would be is another question indeed.

[Weaver]

You could perhaps see an arrangment almost like a cetrifugal-jet-engined type, with a fan behind the prop forcing air through ducts around the cockpit to the engine, and then venting it through a long tube to the rear. Alternatively, the fan could sit on the front of the engine (as opposed to the gearbox), which would have the advantage of it running faster, sucking air in through wing-root intakes and blowing it out through wing-root exhausts, a bit like a Seahawk.

[Empty Handed]

I have a P-63 in bits in storage that I will complete someday as a R-2800 engined variant. It will have semi-annular air inlets on either side of the fuselage, putting the increased frontal area from the engine's bulge to good use. I had given thought to venting the now hot air at the aft end of the bulge, making it all something of a mid-mounted Townend Ring/NACA cowling!

[GTX_Admin]

 Random idea:  thermojet P-39/P-63

[GTX_Admin]

The more I think about it, the more I like the idea of a turboprop P-63.  Engine still behind pilot and still driving prop via shaft.  Could prove an interesting platform in the late '40s/early '50s.

[Daryl J.]

Greg, that would work very very well methinks.

With all the Lend-lease P-39s sent over and the general Soviet approval of the airframe, they continue to develop the aircraft a bit and export it, along with the MiG-15/17 to African and West Asian nations.  Serves well into the 1980s with a few even arriving in South America.   Never quite becomes a P-63.

[elmayerle]

One of my coworkers at Bell is a modeller and looks to combine a P-63D with the wings of the L-39-2.  That should look quite striking.

[GTX_Admin]

With all the Lend-lease P-39s sent over and the general Soviet approval of the airframe, they continue to develop the aircraft a bit and export it, along with the MiG-15/17 to African and West Asian nations.  Serves well into the 1980s with a few even arriving in South America.   Never quite becomes a P-63.

I like the thinking. I would use the P-63 as the basis though.

[kitnut617]

One of my coworkers at Bell is a modeller and looks to combine a P-63D with the wings of the L-39-2.  That should look quite striking.

I've got two L-39-2's in the stash and was thinking something similar with the second kit Evan.  Mind you the Fireball with Sabre wings will get done first ---- 

[apophenia]

The more I think about it, the more I like the idea of a turboprop P-63.  Engine still behind pilot and still driving prop via shaft.  Could prove an interesting platform in the late '40s/early '50s.

How about a ASM.3 Mamba? It's in the right timeframe and roughly the same dimensions as the V-1710. Of course, it only weights about half as much as the Allison. Good chance to push the powerplant rearward and sneak in a c/g fuselage fuel tank.

[kitnut617]

How about a ASM.3 Mamba? It's in the right timeframe and roughly the same dimensions as the V-1710. Of course, it only weights about half as much as the Allison. Good chance to push the powerplant rearward and sneak in a c/g fuselage fuel tank.

You wouldn't be able to move it very much ap', mid-engined aircraft have the engine almost right on the cg point.  It's the reason Rolls Royce started their 'Private Venture' fighter with a mid-engine, they reasoned that if they wanted to install another bigger, heavier, more powerful engine, they wouldn't have to do much changes to the airframe because the cg would still be in the same position.

[apophenia]

Good point kit'. Don't want to turn her into a tail-sitter!

[Weaver]

The more I think about it, the more I like the idea of a turboprop P-63.  Engine still behind pilot and still driving prop via shaft.  Could prove an interesting platform in the late '40s/early '50s.

Or there's this variation I thought of:

2. Twin turboprop Aircobra. Co-axial, counter-rotating props, one small turbine in the nose bay, the other in the engine bay. Front engine has intake and exhaust on the same side, rear engine has them both on the opposite side: this is the only way to stop the rear intake from breathing the front engine's exhaust AND keep the exhaust thrust symetrical. Needless to say, the side doors are abandoned!

[GTX_Admin]

Turboprop P-63:



Maybe even as a counterpart to the Turboprop Mustang?

Note that I envisage this as having a reverse flow turbine akin to the PT6.

[finsrin]

P-51 is fine and gets much attention.  Like seeing P-39/63 getting attention as a turboprop  :)
Worthy of doing in plastic.

[kitnut617]

Turboprop P-63:
Note that I envisage this as having a reverse flow turbine akin to the PT6.

Great idea, there's even a resin Wyvern exhaust  replacement set available in 1/72 to do just that:
 
http://www.hannants.co.uk/product/QB72015

[abtex]

http://alternathistory.org.ua/nesostoyavshiisya-naslednik-aerkobry-ili-alternativnyi-palubnyi-bombardirovshchik-torpedonosets-bell
Is this one of Aircobra kin? Or could have been.



Just wondering.