What If ...

[GregP]

-I am a fan of competition aerobatics. One of the most inpressive aircraft today os the Sukhoi Su-26 type of aircraft. These are mid-wing, radial powered aerobats that closely resemble WWII fighters.

The Su-26 is powered by a 360 - 400 HP Vedeneyev radial that is a wonderful engine, if not enough for a fighter. I think a scaled-up version with a BMW-801, armament, and all the fighter trappings would be a kind of "Super FW-190". It would solve the problem of lack of turning-circle maneuverability very nicely. The gear is easily made retractible.

Any comments?

http://www.tamu.edu/easterwoodairport/images/gaimages/su_26_sm.jpg

[Mark J]

I can't help but notice the faint profile shape similarity to the Curtiss Wright CW-21 Demon. I know they are worlds apart but the likeness is there.

That aside, a very neat looking plane with a reputation that preceeds it.

cheers

[Red Admiral]

I'm not so sure its possible.

The Su-26 weighs 720kg. The BMW 801 weighs 1000-1250kg. Yes, the engine weighs more than the entire aircraft.

Maximum speed is about 450kph already. Low drag canopy and rectractable landing gear. More aerodynamic cowling, possibly a small inline engine and 500kph is probably possible.

[Lightning]

Hi Greg,

I have seen this airplane perform at several airshows, and I agree with you that it was very impressive in its aerobatic display. (By the way, it's this type of aircraft that I prefer to see doing aerobatics rather than warbirds, but that's another discussion.)

As to its being upscaled to the size and weight of typical WWII fighters, I think that the weight increase caused by the addition of guns, ammunition, larger internal fuel supply, antennas, bomb/drop-tank racks, radio equipment, oxygen system, armor, gear-retraction mechanism, etc. would offset the wonderful maneuverability the plane has in its present, purpose-designed form. Also remember that weight increases as the cube of size increase.

In addition to the cited weight penalties, there would also be the issue of drag penalties. Any and all externally added components and protrusions would add materially to drag. And, just as weight increases as the cube of size increase, so does drag increase as its square.

From the above, my conclusion is that modifying a world-class aerobatic performer to be a fighter would have results similar to those produced by modifying a fighter to be an aerobatic competition aircraft: It would go from being at the top of its class to being no better, and probably worse, than average in its new catagory.

Regards,
Lightning

[Dogwalker]

In WWII fighters, was pratically impossible to reduce weight without loosing somewhat important. Pratically every kg more load (not counting the engine) means up to 4-5 kg more weight in the structure to carry it.
Given an 80 Kg pilot, a decent armament, a 700-1000 Kg engine, about 400 kg of gasoline, the radio equipement, the oxigen, the armour and some other little thing, the weight of the aircraft was given, with a little variance from a model to another. Even the so-called "lightweight fighters",like the Ambrosini 207, were surely aerodinamically refined, but not so "lightweight".
So, in my opinion, upgrading the Su-26 to a WWII scale to fit a WWII engine, armament and equipement, hardly means to obtain something different from a La-7
http://www.svetskirat.net/sliken/lavockin/la7.jpg

[GregP]

The La-7 was and is a wonderful fighter. I think it ranks among the best of the war.

[Dogwalker]

Surely it was, and a beautiful plane too.