Hi Paul & group

I'm now on the search of +350 HP spark-ignited engine concept for
record-breaker aircraft design study...
Preferably ~1000 hp on takeoff (with W-injection), and +500 on cruise at
FL300.

And yes, 4-rotor can provide 350 HP with ease, but how to make more
without taking excessive risks? The idea is to design a high-speed twin
that can challenge current FAI speed records on "Speed over Recognized
Course".

Here's some points that i haven't been able to figure out:

- Can we realistically use more than 4 rotors on high-power rotary? Like
5 or 6 ?

- How much sustained cruise power can we expect from each rotor? 80?
Can we exceed that safely? On which condition?

- When pushing the limits, what's likely to fail first on sustained
a-tad-too-high-power cruise conditions? Seals crack?

- And finally, can we get a substantially better altitude performance
with two turbos in series - instead of just a single big one,
dimensioned right to cruise alt and pwr?

Thanks in advance,

Petri Flander

Forget more than four rotors on one e-shaft.

Turbo the four rotor. 1000 HP is a piece of cake with water injection
and inter cooling. The big challenge is cooling the beast. That and a PSRU.
Seals crack only when you let the intake temperature get above 140 to 150
degrees F and detonation occurs. Use a computer to monitor
the intake temperature. It should cruise fine at 500 HP FL 300 as long
as you can keep it cool. The Lemans engine was hardly worn after
24 hours running almost 700 max HP NA. Four small turbo's might be the
way to go for turbo durability reasons. Contact Racing Beat.
They built a 3 rotor with 3 turbo's for a 268 MPH land speed record
in class.

Turbo 3 rotors are making 1400 HP in drag racing as we speak.

Also hook up with Mistral in Geneva. It would be excellent PR for
them. Send email to François Badoux <f.badoux@mistral-engines.com>