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Innovative Thinking?

My head hurts just looking at that.....so many unknowns.
I'm just as interested as anyone to see if it will fly.
Wow.
 
I'd love some insight on the engineering that went into that thing. It may be as simple as "put a big enough engine on a brick and it'll fly". I'm guessing he'll get a 40 hour fly off.
 
Oh my

I saw this on Barnstormers the other day and one comment was stated:

Performance: The RP-4 is designed to be a high performance aircraft.
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Maybe that is a misprint, lol...... should have read: "is designed to be a ????????

If this thing actually flys, it will be amazing. Wonder what the stall speed is???? 180mph+++

The Piranha that my friend has reminds me of this RP-4 a little but because of the very thin wing with the pilot sitting near the tail and his stall speed is around the 125mph range.

This thing looks wild is all I can say. I guess anything will fly if you put a big enough engine in it... :eek:
 
jsherblon said:
Do you need a multi-engine rating to fly it?
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Yes, but you can go for the "Centerline Thrust" option. :)

Just looking at the photos, I can't help but think that they will be in the market for a 500 pound pilot to meet CG.

John Clark
RV8 N18U "Sunshine"
KSBA
 
As a designer and fabricator, I admire the thought and work that has gone into this aircraft. We think we have it so hard building a pre-punched, pre-designed kit!

I'll go out on a limb and say the surface conduction cooling system will be a total failure with maybe 2000hp on tap. The C of G would seem to be impossible here but I don't think they got this far without considering that. The DO335 had one engine in front and one amidships with a drive shaft- seemed like a better idea.

I think the Macchi MC72 seaplane that still holds that world speed record used two V12s in tandem and surface conduction cooling (with a lot more area and copper cladding) It worked to the tune of 440mph on floats so maybe we shouldn't be so skeptical. http://www.oldbeacon.com/gallery/gallery6/gal6-1.htm
The C of G would seem somewhat forward on this one too but it obviously worked.

Totally impressive in 1934!
 
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Ummmm, yeah, innovative.

In the "incredibly naive and dangerously self-confident" sense of the word.
 
Wow

It's hard to tell from the photos, but I think the main gear is further forward than we're used to seeing, so the CG is too. But assuming that's just an optical illusion, given that there isn't a good side view:

Some of that cooling equipment in the tail must be heavy enough to bring the CG somewhere close to a reasonable location. Also, that "thick-walled steel tubing" and 0.060" skin will help!

2" 4130 tubing, 0.095" wall thickness is about 2 lbs/ft
0.060" aluminum sheet is about 0.9 lbs/sq ft.

Adds up in a hurry to weight behind the CG.

I'm guessing, though, that the test pilot will not be an atheist!
 
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rv6ejguy said:
As a designer and fabricator, I admire the thought and work that has gone into this aircraft. We think we have it so hard building a pre-punched, pre-designed kit!

I'll go out on a limb and say the surface conduction cooling system will be a total failure with maybe 2000hp on tap. The C of G would seem to be impossible here but I don't think they got this far without considering that. The DO335 had one engine in front and one amidships with a drive shaft- seemed like a better idea.

I think the Macchi MC72 seaplane that still holds that world speed record used two V12s in tandem and surface conduction cooling (with a lot more area and copper cladding) It worked to the tune of 440mph on floats so maybe we shouldn't be so skeptical. http://www.oldbeacon.com/gallery/gallery6/gal6-1.htm
The C of G would seem somewhat forward on this one too but it obviously worked.

Totally impressive in 1934!
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Ross, I'm with you in thinking that the surface cooling system won't work. I don't think the super thin wing will have enough surface area. I don't think they will run anywhere near 2000 HP though. Also, boundry layer is much more signifigant on a wing with lamilar flow. Aside from having to use super strong materials the thinness of the wing isn't that bothersome. Have you ever figured the thinness ratio of a modern MD-80, excuse me a BD-80. Cg is a bigger concern. This plane would have been a perfect candidate for two 20B rotary engines too. The prop looks weird, but borrows from all that UDF work done years ago. I think that will work fine. The design is truly different, I hope it works for them. Good to see a different take on things once and a while.
Bill Jepson
 
The props are a big effect on this

A buddy of mine who *really* understand airplane design suggests that the props might be very destabilizing. That might explain why the CG is farther forward than you'd think it ought to be.
 
Is this just a bunch of hot air...

I am referring to the air that is going around the wing. :rolleyes:
Would this effect lift? IE the air being heated as it goes by.

Kent
 
Is it me or...

Does the VS look a bit small?

Good luck to this guy! I sure hope it hauls butt!
 
Rotary10-RV said:
Ross, I'm with you in thinking that the surface cooling system won't work. I don't think the super thin wing will have enough surface area. I don't think they will run anywhere near 2000 HP though. Also, boundry layer is much more signifigant on a wing with lamilar flow. Aside from having to use super strong materials the thinness of the wing isn't that bothersome. Have you ever figured the thinness ratio of a modern MD-80, excuse me a BD-80. Cg is a bigger concern. This plane would have been a perfect candidate for two 20B rotary engines too. The prop looks weird, but borrows from all that UDF work done years ago. I think that will work fine. The design is truly different, I hope it works for them. Good to see a different take on things once and a while.
Bill Jepson
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I'm just making a rough plate plate area and Cd guess here. Even with no cooling drag, they'll need 2000+ hp to beat the short course records stated here. They'd have to do 539 mph to take that one. Not sure supercharged V8s will last at this power level for the 100km record. I'm sure you've seen the push/pull twin Wankel powered design on Lamar's site which has never flown?

Cool project. Will it fly? Don't know but I bet it will sound awesome!
 
rv6ejguy said:
I'm just making a rough plate plate area and Cd guess here. Even with no cooling drag, they'll need 2000+ hp to beat the short course records stated here. They'd have to do 539 mph to take that one. Not sure supercharged V8s will last at this power level for the 100km record. I'm sure you've seen the push/pull twin Wankel powered design on Lamar's site which has never flown?

Cool project. Will it fly? Don't know but I bet it will sound awesome!
Click to expand...

The project reminds me of the Sommers Brothers "Goldenrod" land speed record car. The holder of the wheel driven LSR which they held for 20 years. Powered by 4 Chrysler hemis, stuffed into an impossibly small body.
I agree that getting 2 V8s to last for 100 Km at 1000 HP each seems unlikely. lots of things going on there. They sort of tried all of the borderline technologies trying to go fast. Absolute agreement on the "sound awesome" part. Hope it does fly and well. Good luck to them.

Interestingly I believe that Dave Garbers push-pull plane has flown, on one engine. (front) Nothing beyond a short hop though. Terrible cooling problems even with 1 engine. One of my old articles said the Rutan had originally wanted to run 2 3-rotor Mazda wankels in what became the Pond Racer. But Pond brought Nissan money to the party and the V6s were chosen. All of these were innovative airframes, trying to get by on low drag and low HP solutions. I woud love to see one become competitive. Right now Reno has become a P&W radial engine drag race. Hard to argue with an engine displacement that can be measured in cubic YARDS! Wonderful and awesome sounding engines in their own right. I'd just like to see a slightly different shape up there.
Bill Jepson
 
The Merlins of late have had a lot of rod bearing problems attributed to new things being tried. Ever since Dwight Thorn retired, the Merlins have had not so good luck at Reno. It has not been that the round engines are any faster relatively speaking. Be nice to see another V12 victory again in the unlimited class. Maybe Dago's year this year or Voodoo or Strega.

A few years back, they basically outlawed new technology airframes in Unlimited by establishing a minimum weight limit.

The Pond Racer in my opinion would not have been any faster or more reliable with turbocharged Wankels as they just have not exhibited any sort of reliability in turbocharged high output form in road or endurance racing. Full race atmo 26Bs might put out 650-700hp each but this would be far short of what would be required in the Pond to be competitive in unlimited- it would make a formidable Sport Class entry like this however.

The flat plate area vs hp and lower Reynolds numbers that smaller scale aircraft operate at make it a big challenge to get 500+mph. Really what is needed is a narrower NXT type airframe with a Toyota turbo IndyCar engine in it. Proven hp and reliability with low weight and frontal area.
 
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