# Making an "obsolete" fighter into an unlimited racer !

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#### Speedboat100

##### Well-Known Member
It has been done before..in 1989.

It may be possible to do like this too:

Corsair designers had to turn to use wood in ailerons:

Having too many new aspects can be disastrous:

Having 2 car engines does not necessarily have to end in tragedy.

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#### BJC

##### Well-Known Member
HBA Supporter
The Pond Racer’s speed would make it reasonably competitive in today’s Sport Class.

BJC

#### TarDevil

##### Well-Known Member
Such as ...

(I have a fondness for a particular airframe... a sharp eye might note!)
If you don't like round engines...

Looks like Tsunami. Goes to show there's only a few ways to stick a Merlin on an airframe.

#### Speedboat100

##### Well-Known Member
The diameter on an R-2800 is the same as in R-1800.

Anyway..would this LG be too narrow for R-2800 as such ?

#### BJC

##### Well-Known Member
HBA Supporter
How many people are there who are willing and able to invest millions of dollars and a long, tedious, developmental program to go racing once a year with the hopes of winning a nice plaque to hang on the wall? It seems to me that Unlimited Class at Reno has devolved into a WW II nostalgia class.

BJC

#### TarDevil

##### Well-Known Member
How many people are there who are willing and able to invest millions of dollars and a long, tedious, developmental program to go racing once a year with the hopes of winning a nice plaque to hang on the wall? It seems to me that Unlimited Class at Reno has devolved into a WW II nostalgia class.

BJC
Precisely. Until RARA either removes the weight restriction (which is dangerous with 400 mph Sea Fury's rounding pylons) or creates a new "unlimited," the current one will be nothing more than as you described.

Reality is, the current sport class has significant growth potential, speed-wise. Question is, will it draw the requisite crowds and funding?

#### BJC

##### Well-Known Member
HBA Supporter
Reality is, the current sport class has significant growth potential, speed-wise. Question is, will it draw the requisite crowds and funding?
Does anyone know the “back story” on the ending of Red Bull air racing? At least they had a series of races.

BJC

#### Speedboat100

##### Well-Known Member
How many people are there who are willing and able to invest millions of dollars and a long, tedious, developmental program to go racing once a year with the hopes of winning a nice plaque to hang on the wall? It seems to me that Unlimited Class at Reno has devolved into a WW II nostalgia class.

BJC

I don't think that can be the only goal...the 3 kilometre course record comes first.

#### Speedboat100

##### Well-Known Member
I have done shed loads of these racer designs..already 20 years ago.

I think this was TIGER SHARK II.

#### mcrae0104

##### Armchair Mafia Conspirator
HBA Supporter
Log Member
If you don't like round engines...

Looks like Tsunami. Goes to show there's only a few ways to stick a Merlin on an airframe.
Unfortunately there is a tiny scale difference between the P85 and a Mustang's FWF...

#### TarDevil

##### Well-Known Member
Unfortunately there is a tiny scale difference between the P85 and a Mustang's FWF...
View attachment 92920
I'm quite aware of that... It's why I said a "P85 on steroids."

Scale the plane up, scale the engine down... you may choose.

I'm just having fun... hope you are.

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#### mcrae0104

##### Armchair Mafia Conspirator
HBA Supporter
Log Member
I'm quite aware of that... It's why I said a "P85 on steroids."

Scale the plane up, scale the engine down... you may choose.

I'm just having fun... hope you are.
Indeed.

And I hope you'll keep the mashups coming.

HBA Supporter

#### Speedboat100

##### Well-Known Member
Unfortunately there is a tiny scale difference between the P85 and a Mustang's FWF...
View attachment 92920

In my Tigershark above the engine is being buried into the sept wing..all away up into the spar.

#### Voidhawk9

##### Well-Known Member
HBA Supporter
In my Tigershark above the engine is being buried into the sept wing..all away up into the spar.
No point in carrying around empty space on race day.

#### Speedboat100

##### Well-Known Member
No point in carrying around empty space on race day.

Right, but it means that you have to carry the fuel in the wings...unlike in Tsunami.

#### cvairwerks

##### Well-Known Member
Does anyone know the “back story” on the ending of Red Bull air racing? At least they had a series of races.

BJC
Publicly, what I saw was a lack of viable locations and a lack of patrons.

#### Swampyankee

##### Well-Known Member
2020-Feb 4th

Ahoy, HomeBuiltAirplanes,

Dark-of-the-night thoughts ::::

Reno Racers: Very high level development, but innovation ????

Sheeessh !!! And youse-guys want to build just another almost-the-same ‘critter’ as everyone else is flying ???? !!!!

It comes to my mind that the only significant innovative ‘things’ which I have seen there are vapor phase cooling, and (years ago), the clean-sheet Pond Racer.

At Reno, I was talking with an Aerothermodynamicist, (my thesis field) whose name, I no longer recall, but his was on more than half of the landing gear doors present.

My question was about vapor phase cooling endurance, and he noted that at low power, it was pretty good, with the P51 – so rigged -- having flown from Portland to Van Nuys.

The Pond Racer sounded like an immense window fan. He remarked that they were going to need to automate a lot more things, because the pilot workload with cooling doors and spray nozzles and all else was overwhelming. Unfortunately, no longer needed.

Sports Racers:

The Reno Go-Fast Sports Racer Rules: … ‘Aircraft are to be powered by an internal combustion engine or engines totaling no more than 1000 cu in.’

I’ve neither seen, nor heard any talk about a pair of 495 cu/in seriously hot engines installed in an appropriate --- say a tandem engine / tilt-wing / extension shaft airplane.

Of course, the extension shaft is no casual thing. A comprehensive dynamic analysis is in order, along with appropriately measured results. The development of such may well be made easier by using a clutch to de-couple the shaft during start, and up to some certain rpm.

BTW, a seriously dangerous soul is one with a shop full of high tech tools who can craft a PSRU, but is ‘unlettered’ in his ability to technically analyze the dynamics of his ‘creation’, nor is he capable of measuring the result.

Tandem engines were figured out by Bugatti 80 years ago. Too bad that the beautiful replica airplane did not have a proper dynamic shaft analysis / measurement. What I read about the loss was ‘clutch failure’. I’ll bet that a lot of unplanned for torsional dynamics were very involved with that clutch failure.

The wetted surface of such an airplane could be about the same as a single engine critter, and with twice the HP, I suggest that a well-done airplane like that would absolutely rule the Sport Racers, and scare the crap out of the unlimited guys.

WHY is such an airplane not seen??? I cannot be the only guy to have had such ideas.

I believe that there is plenty of \$ in the hands of the Reno Racers to do such. ??????

Enjoy /s/ Bob
They may have a lot of money, but the teams interested in a completely new Unlimited airframe don’t have enough. For one thing, there are few high-powered piston aircraft engines except the big radials and the ex-military Allisons, Merlins, and Griffons. Adapting one of the high-powered auto or outboard engines would be non-trivial.

#### TarDevil

##### Well-Known Member
Adapting one of the high-powered auto or outboard engines would be non-trivial.
True, but at least we are seeing efforts. It's aviation's only real hope for 400+ hp piston power.
As others stated previously, one race a year will not accelerate that trend.

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