Whiffing an Me509

[Librarian]

OK, so whiffing an Me509 is almost an oxymoron but I'd really like to stick a radial engine where the inline goes. Has anyone attempted this or seen it happen?

Can a radial engine have the extended shaft as do inlines eg P-39s?

Would a couple of large scoops on the side of the fuselage be enough to air cool the engine? There's a huge radiator scoop under the fuselage that could be altered to look somewhat like the F-16's air intake.

Any advice gratefully appreciated.

[Chap]

Librarian,

Yes, in fact there is a precedent. The Piaggio P.119 was setup as you describe (in a tailwheel configuration). http://en.wikipedia.org/wiki/Piaggio_P.119



Looking forward to the results,
Steve

[TallEng]

You could use an Annular radiator to cool it, like on the Fw190D and various other designs.
It seems the Germans were very fond of them.
and why have scoops? why not an inlet all the way round the fuselage? that way the engine would
be cooled evenly. (might not need the Annular radiator then) of course it would also help
if the fuselage were round in cross section were the engine was fitted.

Regards
Keith

[rickshaw]

Cooling is the biggest problem with such designs.  The Japanese also found problems with the use of extended drive shafts when they attempted to use on on the Raiden to improve the cowling shape.  They would more than likely also found similar problems and cooling ones on the Kyūshū J7W1 Shinden, as well.   The thing is, radials need loads of air to cool them, however, if you used say a Jumo 222 or BMW 803 which were effectively liquid cooled radials, then you'd just end up with a portly fighter, with a clean aerodynamic nose...

[Librarian]

Thank you very much. I do like the Piaggio, reminds me of a P-47 version with a big scoop. I was just having a walk and thought about the air intakes on an A-4 Skyhawk, with the ducts and fan blades. Switch them for the German design (like on the earlier 190s) and it could be a winner. It's difficult to whiff sometimes and remain in the realms of reality. I just like the look of the 509 but trying to avoid inlines.

[Dizzyfugu]

Cooling is the biggest problem with such designs.  The Japanese also found problems with the use of extended drive shafts when they attempted to use on on the Raiden to improve the cowling shape.  They would more than likely also found similar problems and cooling ones on the Kyūshū J7W1 Shinden, as well.   The thing is, radials need loads of air to cool them, however, if you used say a Jumo 222 or BMW 803 which were effectively liquid cooled radials, then you'd just end up with a portly fighter, with a clean aerodynamic nose...

They did, and that's why they added tose extra air scoops on the flanks of the original intakes.

Engine diameter might also be an issue. A BMW 803 is pretty compact, though, but I think that it is certainly bigger than a Me 109/309 fuselage. A belly scoop/tunnel sounds most practical to me, too - you not only have to get cool air in, but also the hot air out, so a P-47H-like arrangement would be most practical. On the other side, "pouches" on both flanks would also look cool, and they'd widen the fuselage for the radial behind the cockpit without having a barrel-shaped body AND the extra belly thing?

[jcf]

The BMW 803 was big, 63" diameter, 9,100 lbs.

Even the BMW 801 is larger than folks realize, 51" diameter, 2,226 lbs, 41.8 litre displacement.

Also a radial doesn't have to be air-cooled, and, as stated,  another option is radially arranged
multi-bank engines like the Jumo 222 or Wright Tornado, both of which have smaller diameter than
similar displacement 'normal' radials.

http://en.wikipedia.org/wiki/Junkers_Jumo_222#General_characteristics

http://en.wikipedia.org/wiki/Wright_R-2160_Tornado

Extended driveshafts on radials are just as 'easy' to do as with an inline, in that the problems
are the same. 

[Librarian]

Aarrgghhhh! The lazy monster is pointing me in the direction of the Wright Tornado. I can still have the bumps on the side to accomodate it and the nice big air scoop underneath would be perfect. It'd look a liitle like the XP-69. Oh yeah .

[wuzak]

Curtiss used an extansion shaft on their front mounted R-1830 to try to reduce air cooled engine drag in the XP-42:



The Deerhound was a compact radial - 44" diameter. Also used ducted air for cooling (flowed from rear to front in the case of the Mk II).



Alternatively, there were air-cooled in-lines. Admittedly most lacked power, but there was the Exe of 1150hp and Pennine of 2800hp.

[Librarian]

Been doing a bit of fiddling. With a few precision cuts in the fuselage its possible to fit the fan-can from an A-10 into the fuselage. Then using a large long range Luftwaffe fuel-tank strategically cut and sanded on the fuselage sides everything blends in nicely. I'll investigate further when I've finished my current projects.