Twin 720 Racer ?

[First time Juke]

Re: Twin 720 Racer ?

CG problem there then ? It cannot be one or the other of them.

Will I show you my older 2 x V-8 design ?

[bflynt]

Re: Twin 720 Racer ?

Somewhere in that same thread they state it would race in the unlimited class by getting a weight waiver or adding water ballast into the wings.

While the linked thread is old he posted just a couple weeks ago, in an unrelated thread, that the project was moving forward.

Bryan

[wallstreet]

Re: Twin 720 Racer ?

I have heard of a Southern California project in which a shortwing, normally aspirated Aerostar is being equipped with IO-720s in place of the stock IO-540s as an experimental-registered aircraft.

[AirDOGGe]

Re: Twin 720 Racer ?

Note in the front view the right side shows a pusher while the left side shows a tractor. I'm pretty sure this indicates that the design would be either a twin pusher or a twin tractor but not a four engine push-pull!


Surely the designer does not have it set up as a twin with a pusher on one side and a "puller" on the other, right?

It's a pusher-puller on both wings...4 propellers...



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From what I've read, this one really is intended to be a 4-engine aircraft. The "layman" aircraft designer can certainly come up with about anything cool-looking, being unrestricted by all those aerodynamic, powertrain, vibration, flutter and structural issues (heh-heh).

I know, because I was there once. One can see so clearly, yet be so blind...

HIS words:

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Since you need to add more weight to race in the unlimited category here's a racer that will fit the bill using four supercharged big block V8s in a push pull manner with two on each wing. Each one will put out 800hp with moderate reliability and could be pushed to 1200 to 1500hp or so for short bursts without breaking. So you would have 3200 to 5000hp to play with. The old warbirds wouldn't stand a chance.

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Of course the tandem-engines-in-a-single-nacelle layout is nothing new. Many vintage aircraft from the days of the early biplanes and beyond used tandem engine arrangements to compensate for low engine power.

Some seaplanes used tandems too, and there were still more who were designed to have tandems but never got the chance to fly or even get built, like this prototype Dornier:





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[First time Juke]

Re: Twin 720 Racer ?

French tried it too; http://www.youtube.com/watch?v=6grevNQCpno

Planes were converted to bombers...one bombed Berlin in 1940.


How about putting 2 more engines on this one ?

http://www.youtube.com/watch?v=KQuGNWYAknI&feature=related

[First time Juke]

Re: Twin 720 Racer ?

The tail volume coefficient should be 0,07 in a twin..0,04 in a homebuilt single engine and 0,02 in a glider.

I have been counting these a lot since I am designing a plane of my own.