The Pond Racer.....Rutan's Watergate

[speeddemon]

Re: The Pond Racer.....Rutan's Watergate

What I want to know is... how the hell did a severe engine failure become a fire in the (centrally located) cockpit?

The 'real' answer will probably never be known...however, speculation points at the shape of the wings, the negative sweep, and how fuel leaking from the boom could run along the leading edge of the 'inner' wing section, and lead....right to the cockpit.

[First time Juke]

Re: The Pond Racer.....Rutan's Watergate

The Falconer engines are the closest thing to a counterexample I can think of right off, and they're SO far removed from their automotive roots that they're not even a good counterexample.

Do they have a supercharger or a turbocharger of any kind ?

[jarrodeu]

Re: The Pond Racer.....Rutan's Watergate

Do they have a supercharger or a turbocharger of any kind ?

Yes, go down to the bottom of the page.

http://www.thundermustang.com/falconer.htm

Did the pond racer have dual ignition?

Jarrod
post 200

[440_Magnum]

Re: The Pond Racer.....Rutan's Watergate

Do they have a supercharger or a turbocharger of any kind ?

The basic engine has been both turbocharged and supercharged for other applications (automotive and boat). However, I don't *think* its ever flown with forced induction. The Thunder Mustangs that have raced at Reno are normally aspirated.

http://www.falconerengines.com

Even though I think the Falconer is the best effort at adapting automotive-based technology, I have to say that reading the spec sheet and seeing an automotive Fluidampr harmonic balancer on the parts list kinda gives me the willies for an aircraft application. There's certainly nothing wrong with a Fluidampr... but the idea of an aircraft engine that *needs* a harmonic balancer just doesn't feel right in my gut. And no, I really don't have any concrete engineering reason for saying that.

[MRussell]

Re: The Pond Racer.....Rutan's Watergate

The 'real' answer will probably never be known...however, speculation points at the shape of the wings, the negative sweep, and how fuel leaking from the boom could run along the leading edge of the 'inner' wing section, and lead....right to the cockpit.

Gosh, that would mean two separate, "independent" failures (engine seized + fuel lines / pump / tank began leaking and ignited within the cockpit) that occurred basically simultaneously!

[speeddemon]

Re: The Pond Racer.....Rutan's Watergate

Gosh, that would mean two separate, "independent" failures (engine seized + fuel lines / pump / tank began leaking and ignited within the cockpit) that occurred basically simultaneously!

I'm getting out of my range of direct knowledge here, but my thought is that the 'fire' didn't happen until after he impacted the ground. If I remember right, he reported fuel and fumes in the cockpit, but not an actual fire--one of the speculations as to why he didn't blow the canopy, which had explosive charges on it.

Again...not preaching gospel, just trying to remember all that has been said and discussed on the matter.

I miss Rick. A very classy guy.

[Wild Bill Kelso]

Re: The Pond Racer.....Rutan's Watergate

Being that it ran on Methynol I often wonder if he had a fire and didn't know it until it was too late. It has happened in Indy cars before.

[Unregistered]

Re: The Pond Racer.....Rutan's Watergate

but the idea of an aircraft engine that *needs* a harmonic balancer just doesn't feel right in my gut. And no, I really don't have any concrete engineering reason for saying that.

Many aircraft engines do have harmonic balancing schemes in the form of hanging/floating counterweights on the crank.

[MRussell]

Re: The Pond Racer.....Rutan's Watergate

Being that it ran on Methynol I often wonder if he had a fire and didn't know it until it was too late. It has happened in Indy cars before.

Someone earlier posted they had to run non-methanol autogas due to capacity constraints. The NTSB report states they were running "automotive blend A-10-P" in the accident flight. Does anyone know if that's methanol or not?
I also miss Rick... Dreadnought was never more fun to watch than when he raced her.

[spacegrrrl]

Re: The Pond Racer.....Rutan's Watergate

There was definitely a fire before the crash. The Pond was running on gasoline. By the way fuel leaks were extremely common on the pond. Rick told me just before he took off for that last flight that this was sort of a "last hurrah" for the racer before it was retired to museum. They had just replaced at least one of the engines before getting to the race. CFD analysis of the design showed definite flow inward towards the pod as a result of the foward swept wing so burning fuel would definitly flow in that direction.

As for the engine's suitability to being raced in a plane I don't think you can say anything other than it certainly wasn't sorted out yet in the Pond. Lots of the problems were not directly the fault of the engine but a result of the installation. For example I remember being told that a lot of the engine control and ignition issues the first year were a result of poor inital choices for the way wiring was run and that way ignition wires were installed. I don't think that says it couldn't have been make reliable. Just look at how long it took to get many of the engines that are common in warbirds today reliable. I've heard it said that you should never develop a new motor and a new airframe at the same time. I expect there is some wisdom in that thought.

I think the question you should really ask when you look at Rutan's take on how to build a better racer was "Did the Pond prove to be a better configuration than something more convential could have been?" When I ponder that I would say no. here are whay I think the Pond was a poor design.

1. Too much intersection drag. Chase down a copy of "Fluid Drag" and you discover that one of the biggest sources of airframe drag is where surfaces intersect. The pond has 6 wing intersections and 7 tail surface intersections. A convential airplane has 2 wing intersections and 3 tail surface intersections.

2. Forward swept wing cause a big high pressure flow into the center pod. Bad for drag, bad for trying to keep the pilot seperate of the dangers of the power systems.

3. Standard issues surrounding assymetrical thrust that most twin engine aircraft face. To be fair Rick said the Pond was very well behaved one one engine and overall he enjoyed flying the Pond.

So how would the same effort spent on a inline thrust design like the DO-335 have done? Or perhaps something that geared the two engines together? More potential I expect.

One thing that would have improved the chances would have been to develop the powerplant seperately before trying it in a new airframe so that the issues that were related to the engine installation could be more easily identifed since the powerplant itself would have been previously characterized. Also, methanol is so tempting but to date no one has overcome the issues alternative fuels have presented. That should have been the last thing brought into the program once everything else was sorted out.

I do hope someday we see another ground up new race design. The silly weight limit seems to make that less likely but who knows. I guess is it has to be 4500 pounds then maybe a nice V-24 from 3 large block American V8s makes sense. Invert them, use three chain drives to a a common drive shaft above them, you'd have a reliable reduction, you could use some sort of clutch to allow one engine or more engines to fail and be brought off line. If the plane has to be big, might as well make as much of it engine as possible!

Michele

[First time Juke]

Re: The Pond Racer.....Rutan's Watergate

So how would the same effort spent on a inline thrust design like the DO-335 have done? Or perhaps something that geared the two engines together? More potential I expect.
Michele

Michele,

How about powertransmission of the Gallaudet Chummy1 ? This princible based layout appered on one of my scetches in 2001 - 2002 here in AAFO.com also. It does not have to be chains and spockets.

http://img398.imageshack.us/img398/9519/gallaudetchummy15zd.jpg

rgds,

Juke

[GeeBeeZ1931]

Re: The Pond Racer.....Rutan's Watergate

Whenever Burt accomplishes something really neat....as he has done so twice in the last year with Fosset's Global Flyer and the spacecraft...I always think..about how screwed up the Pond Racer was...designed by Burt. It's kind of spoiled anything else Rutan has done since then for me....no matter how great it is. I just can't get over it....And don't get me wrong I still like Burt....but I always have a sagging feeling about him ever since that whole debacle. I'm sure there's some people who might feel the same about Greenamyer after his B-29 fiasco.

John

Even a fool is considered wise when he remains silent.........as you should have.

[First time Juke]

Re: The Pond Racer.....Rutan's Watergate

I answer my question myself...the air intake of Pond Racer can be seen here:



My humble opinion would be that this cooling did not create ( as much ) positive ram air effect as it does in the Mustang ( 700 kp ).

I have found this thread very learning and worth while, despite opposite comments.

There are several 1000 + hp aeroplanes in aviation history where the airplane did not fly many yards after the take off. In this respect Pond Racer went much further and still is the fastest plane equipped with a car engine derivative as far as I know ( 440 mph ? ).

It is an achievement of nobody else than a master in aviation. Whether the fire in the plane is due to Burt's design ...I find it somewhat doubtful. The fact that Pond did not achieve 528 mph is certainly partially caused by the engines...the other part remains unclear.


best regards,

Juke T

[John H]

Re: The Pond Racer.....Rutan's Watergate

Even a fool is considered wise when he remains silent.........as you should have.

No I'm not going to shut up about something that gave me nightmares and emotional turmoil.

John

[spacegrrrl]

Re: The Pond Racer.....Rutan's Watergate

I answer my question myself...the air intake of Pond Racer can be seen here:



My humble opinion would be that this cooling did not create ( as much ) positive ram air effect as it does in the Mustang ( 700 kp ).

I have found this thread very learning and worth while, despite opposite comments.

There are several 1000 + hp aeroplanes in aviation history where the airplane did not fly many yards after the take off. In this respect Pond Racer went much further and still is the fastest plane equipped with a car engine derivative as far as I know ( 440 mph ? ).

It is an achievement of nobody else than a master in aviation. Whether the fire in the plane is due to Burt's design ...I find it somewhat doubtful. The fact that Pond did not achieve 528 mph is certainly partially caused by the engines...the other part remains unclear.


best regards,

Juke T

A very well know drag reduction specialist did a very comprehensive analysis of the Pond racer and his conclusion was there was no way you could ever get it go much faster because of the poor airframe configuration choices. As I mentioned in another thread there is a point where you can't expect HP to increase your speed significantly. Also the Pond didn't catch fire because of the "design". It caught fire because of the issues surrounding trying to debug the powerplant and supporting systems. Planes can catch fire. Sadly my favorite racer did just that in front of my own eyes in Phoenix and met its doom and I'd like to point out that the Super Corsair had an aircraft engine so to blame the "auto" engines is just bad thinking.

Don't forget some of the other bizzare Rutan designs that when nowhere. Like the Grizzly bush plane and the Ares jet fighter thing. What I don't understand about Rutan is that he seems to go out of his way to pick non-standard configurations when there is no immediate advantage to the selection. Again, compare a Longeze and and RV-4 head to head and the RV wins hands down. Or a LongeEze and a Lancair Legacy or a Glassair. The LongEze looks different and some people seem to like that but in terms of performance and handling (or even practical things like having to go through the gyrations you have to with a LongEze to keep it from falling over backwards on the ground) the LongEze doesn't match its convential configuration competitors.

I understand how you can become focused on non-conventional aircraft configurations. Right now I think a flying wing is the way to go in sport class and F-1 and that someone needs to revive the Arup or some other low aspect ratio design as an SLA homebuilt. But I'd be the first to admit I could be wrong. In a very real way Darwinian forces are why almost every aiplane you see today has the same basic configuration.

Michele