Re: The Pond Racer.....Rutan's Watergate
My 10 mph reduction idea is based on this.
They are like two fists pointing up.
My 10 mph reduction idea is based on this.
They are like two fists pointing up.
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Re: The Pond Racer.....Rutan's Watergate
I'd never expect to see the actual techniques of optimizing stack thrust out in the open. What I'm curious about is not so much how you'd optimize, but how you'd even measure or estimate/predict the results. That's got to be a difficult thing to quantify, because changing anything affects both thrust and drag. Of course once someone comes up with a good method, THAT knowldedge would probably be guarded with big dogs tooOriginally posted by speeddemon
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Re: The Pond Racer.....Rutan's Watergate
The comparison is between just what you just described, the top speed of a spit with straight stacks directed 90 degrees to the airflow and one with longer stacks projecting out in the airstream and directed rewards to add exhaust thrust to prop thrust.You have to be careful now. That 2 mph has been gained in a comparison to nothing...original Spit ( 5054 ) had only holes as exhaust in the fuse and gasses came in at 90 degree angle from the fuse.
The augmented rear-facing exhaust pipes were called "ejector" exhaust stacks. The Hurricane also benefited from ejector exhausts.Comment
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Re: The Pond Racer.....Rutan's Watergate
I stand corrected that the engines were NOT "what they used in F1 racing"... but if you check the specifics on this racer and what has been put in print - as well as talk to a few that probably know more then what was printed (like Kerchenfaunt) - the original design called for a custom alcohol fuel mix to be used as fuel, not gasoline. In fact, there was a lot of concern about the pond racer ever making it to Reno in 91... since ferrying the aircarft from Mojave require much more time then the "less then 20 minutes" full power duration the aircarft had buring "methanol". Luckily, all they had to do was change the computer chip to allow the aircarft to fly on gasoline... but then again, just because it could fly on gas doesn't mean it was designed for race speeds using this fuel.Originally posted by HiredBitSlinger
Reguardless... My appologies for using an inacurate comparison. My main poiint was the wet wings were not designed large enough to hold the required amount of design race fuel, with adaquate provisions for enough safty reserves. Therefore they had to burn race gas, which caused the engines to operate at a much higher temperature then they were intended to, and there was not sufficent leeway in the design to allow for this contingency... in my humble opinion
Again, sorry for the confusion.Mark K....
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Re: The Pond Racer.....Rutan's Watergate
Thanks for the clarification. It is a good and significant point.Originally posted by CobraMy main poiint was the wet wings were not designed large enough to hold the required amount of design race fuel, with adaquate provisions for enough safty reserves. Therefore they had to burn race gas, which caused the engines to operate at a much higher temperature then they were intended to, and there was not sufficent leeway in the design to allow for this contingency... in my humble opinion
Again, sorry for the confusion.
Dan PlunkettComment
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Re: The Pond Racer.....Rutan's Watergate
So wouldn't designing a racer with insufficient fuel to actually finish a race be considered poor design? Yet another thing Rutan screwed up on the Pond.
MicheleComment
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Re: The Pond Racer.....Rutan's Watergate
As I recall the original purpuse that the PR was designed for was an attempt on the speed record. The exact specs were to be able to do the 3 passes through a speed trap. The radiator cooling inlets were to be removed and sealed. The radiator compartment was to be flooded with freon to boil off for cooling. The fact it ran on meth would help reduce engine temps to allow this to potentially work. Burt was vacation on a sailing boat and was watching the dolphins ride the bow wave and that was some of the inspiration for the design.Originally posted by spacegrrrl
The air racing was secondary as a use for the aircraft. That is why it had some shortcomings that seem so large to our eyes.
These were some of the things I was told when I worked on it.
Rich PComment
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Re: The Pond Racer.....Rutan's Watergate
Michele no personal offense, but I am dying to know what credentials you have that qualify you to make such unlimited, repeated, biting criticisms of every decision you think Burt made in the design and setup of the PR??? Furthermore, how do your credentials qualify you to make high-level criticisms of his earlier designs like the EZs?
It appears you've had these feelings about Burt and his designs since long before Space Ship One flew, and I would think your common sense would have you pipe down a bit after that single demonstration of genious... I mean, is the guy well-qualified to design aircraft, or not? It must be tough for you to have the audacity to thumb your nose at someone who's accomplished what he has. You realize many people are comparing Burt's abilities to those of C.L. Johnson, right? That's pretty much the ultimate compliment and public endorsement for someone in his field.
Most of what you contribute to this forum is well-researched and high quality stuff. I am absolutely stumped about why you would continue slash at Burt's efforts as you have. It seems downright personal and hateful. You're entitled to your opinions, but what gives?_________
-Matt
Red Bull has no earthly idea what "air racing" is.Comment
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Re: The Pond Racer.....Rutan's Watergate
This does seem to make more sence... that air racing was a secondary use for the plane. Don't get me wrong - I really loved the Pond Racer as a Reno Unlimited Aircarft, and maybe that (as well as the name) biased me into thinking it was a purpose built "racer" and not a record speed run aircarft design. Thanks for sheding some light into this discussion Rich. It does explain a great many things, including why it never really showed it's true potential at Reno.Originally posted by 51fixer
I would add that much of the press on this aircarft was also biased towards air racing. If I recall correctly, Bob Pond stated that his love for vintage WWII aircraft and his dissatifaction (for the lack of a better word) with seeing them hacked up, modified, ect. to be flogged at Reno was the main reason why he decided to finance this project. Then again, this was only what was in print.
Thanks again for the post Rich
Mark K....Comment
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Re: The Pond Racer.....Rutan's Watergate
Originally posted by MRussell
I had become casual friends with Rick and he told me quite a bit about the Pond, in fact he gave me Red Knight hat pin just before he got in the plane for that last flight. I still remember watching him go down and thinking to myself it was for nothing. At that point everyone knew it could never be competitive and after that Reno Rick said the Pond was going to be retired. I had watched the Pond closely every every appearance it made in Reno and saw what a train wreck the program was in the beginning. I still remember the Pond on the flight line dumping huge amounts of fuel on the tarmac the first year from the fuel leaks that seemed to plague it from the beginning. Was there ever a Pond race flight that didn't end in a mayday? I have also talked to people I really respect about the realities of the pond in terms of its aerodynamics and have also studied aerodynamics extensively myself and clearly see issues with the decisions made regarding the layout chosen. Rutan has done some great things but the Pond was not one of them and in a lot of ways I believe set back the chances of really creating an "out of the box/non-warbird parts" racer. If the money spent with Rutan had gone to some other program with a better designer we might see a much healthier unlimited class full of really new and innovative aircraft. Just look at the argument you see in these forums about how "car engines can't be used in airplanes" that ignore the hundreds of automotive conversions being flown every day in homebuilts across America.
As to the EZ, I think the way you tell a really great aircraft design is how well it performs overall. The EZ does one thing well and not much else.
Finally, do you consider Space Ship One an unqualified success? Every full power flight it experienced periods of loss of control during ascent that were never resolved. More a testament to the "right stuff" of the pilot rather than the perfection of the design. Great accomplishment for sure but one that seemed to also involve a great deal of luck.
So summary about my feelings.
1. The Rutan's choice as the designer of the Pond racer contributed to the loss of someone I considered a friend and probably kept us from seeing a real viable racer that met Pond's vision of a racer that did not deplete the limited warbird resources and that could be built in volume.
2. The EZ is an interesting design that makes a lot of sacrifices for a small single advantage and I would argue if a similar focus had been made to a more conventional design you would not only have the efficiency, you would have increased versatility. Just look at the Smith AJ-2 CAFE racer or the Arnold AR-5 if you want to understand what I mean.
3. The fact that every Space Ship One ascent encountered uncontrolled stabilities issues leaves a bit of a blemish on the design as well. To be fair that program pushed so many boundaries that these were the only obvious issues is pretty amazing.
To compare Rutan to Johnson is simply absurd! Let's see, Kelly is attributed with designing:
P-80 (in 143 days!)
X-90
X-7
T-33
F-94
F-104
F-12/SR-71
U-2
C-140
and contributing to:
Orion 9D
Model 10 and Model 12 Electra
Model 14 Super Electra
P-38
Lodestar
B-37
PV-1 Ventura
p2V Neptune
Constellation series
C-130
Not to mention all of the aviation awards Kelly was awarded! Kelly is an aviation legend. Rutan is a very interesting historical figure at best. An interesting historical figure that has contributing nothing of widespread application in aviation of any form and who has actually set unlimited air racing back by virtue of his oddball design tendencies. He had a rare chance to really do something amazing for air racing and he blew it.
You asked "is the guy well qualified to design aircraft or not?" That depends on your criteria. He has had some interesting successes developing aircraft with very specific single missions. Has he created a single aircraft with wide spread application and commercial success? Not at all. Has any aspect of his aircraft designs found any widespread application or success? No. Is he able to build a successful air racer. Seems not.
What he has done is create a very successful company to do one off prototype work for a variety of mostly military and goverment organizations. That is the most amazing result of the EZ homebuilts. That him building a VW powered foam and fiberglass homebuilt leading him to create Scaled Composites is something I have to say is worthy of praise.
MicheleComment
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Re: The Pond Racer.....Rutan's Watergate
Sadly I have not been able to unpack my old EAA magazines so I can't find the early articles but I don't remember anything about the Pond being for a speed record. I always remember it being something that Pond funded to try and develop a racer that wouldn't continue to deplete the remaining warbirds. I believe when we were hearing the crazy speed preditions before it flew there was talk of trying to set a record but I don't buy it was built for that. It was built to be a racer that could be sold as a kit and not use warbird parts.
MicheleComment
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Re: The Pond Racer.....Rutan's Watergate
Michele,Originally posted by spacegrrrl
I would have to mostly agree with you but will offer these comments. I too was there when Rick left the course, had an engine seize and disappeared into Griffon Gulch. I had strapped him in and put the canopy on for him. I drove the Pond van off into the desert to the crash site. I also worked to examine the crash site and pick up the pieces of the aircraft and his found things such as soles of his shoes. I know that Rick would probably left flying the PR. That is a personal feeling I have. They had brought in several people new to the program. They were running dyno tests with good results using these new guys. We had overcome a few long standing issues that poor engineering had created. Rick said to us that the PR was running smoother than his T-33. Several long term costly items were agreed to prior to Reno. One of which was a total tear down of the airframe. My feeling is that it wasn't going to be retired, at least not yet.
If one wanted to build the fastest dragster in the world, (I didn't say in a 1/4 mile) one would use a set of priorities to design it. If you also wanted to race it at sanctioned drag races then at some point some compromises would have to be used. There was at some point a desire to have a speed record with the PR. That was what I was told was a priority in the design. It was also supposed to race. All this designed by people who hadn't built a racer using engines that had never flown. It became a multi-million $ program that couldn't perform safely, so it was given to Steve Hinton to prove that it was worth continuing. His crew made many advances in it's operation over 2 years and it seemed to have alittle more that it could give.
What is printed in magazines I would say is not always the whole story.
I walked the crash site with Burt and the engine guy along with the FAA. That was the one time I ever met him. It was also the hardest thing I have ever had to do.
Sorry to ramble but it is late.
Rich PComment
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Re: The Pond Racer.....Rutan's Watergate
FYIOriginally posted by 440_MagnumThe 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.
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.
Some of us in the homebuilt community are using them on good ole aircraft engines. in my case a lycoming 0320. My engine has 10:1 pistons and a very light 8-10lb high tech carbon fiber prop. The firing pulses with such a light prop make the engine run rough, especially at medium and low power settings .
Addition of a 12 lb harmonic balancer smooths out the impulses and makes life quite bearable, both on engine and pilot.
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Re: The Pond Racer.....Rutan's Watergate
Yes, the EZEs were built for one reason...To create a spin-resistant general aviation aircraft (due to all the pilots being lost back then and still lost today in spin accidents). He did that quite nicely. The Rutan canards were never designed to be the fastest in their class nor the most comfortable nor the best load carriers.As to the EZ, I think the way you tell a really great aircraft design is how well it performs overall. The EZ does one thing well and not much else.
It did what it was designed to do, did it not? (win the X-prize) I haven't seen any other non-government funded vehicle even come close to acomplish what it has done fro the amount of money involved. Only the US and Russian space shuttles have done anything similar (a manned vehicll fly up into space and land like a plane) , and those projects had billions of dollars and many, many years to work with.Finally, do you consider Space Ship One an unqualified success?
Even the aforementioned space shuttles were just cargo for the most part, strapped to huge rockets...SpaceShipOne was a self-powered stand alone aircraft/spacecraft.
Complaining about the stability of SpaceShipOne is like complaining about the stability of the Wright brother's first powered aircraft. Both were/are private civilian projects at the forefront of a new era in flight, and have little or nothing to compare too. If you want more then we will have to wait for the Rutan-designed passenger-carrying sub-orbital vehicles that are in the works right now. Those no doubt will take passenger confort and smoothness of flight in consideration when designed.
To compare Rutan to Johnson is simply absurd! Let's see, Kelly is attributed with designing:
Kelly also had the benefit of an army of Lockheed engineers, designers and manufacturing resources in producing his aircraft ideas, plus the budget to develop and produce them.
I sincerely believe that if Burt had been placed in the same role in the same situation during that same time period we'd be just as impressed at what came off the Lockheed factory floor.
I mean, if you want to speak of aircraft that "do one thing well and not much else" then let's speak of the F-104 (designed to go fast, but is tricky to fly, lands too fast and requires huge amounts of airspace just to turn around), the U-2 (Designed to fly at very high altitudes but is VERY tricky to fly in this enviroment, is very fragile, requires the pilot wear the equivalent of a NASA spacesuit and demands much greater respect and awareness when landing compared to other aircraft) or the SR-71 (costs a small forture to keep flying, leaks large amounts of fuel on the ground, cannot even take-off with full tanks and requires HUGE investments in maintanance and upkeep).
Aircraft engines suffer from greater longitudinal and rotational vibrations and damaging harmonics than most (if not all) cars do. Many dedicated aircraft engines benefit from larger bearings, more bearing races and a beefier crankshaft.....That's something a converted car engine does not enjoy. They need all the help they can get.but the idea of an aircraft engine that *needs* a harmonic balancer just doesn't feel right in my gut.
.Last edited by AirDOGGe; 12-04-2005, 12:28 AM.Comment
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Re: The Pond Racer.....Rutan's Watergate
Michele:
Thanks for promptly answering and not taking my post personally. I respectfully disagree with almost every single thing you wrote, but I appreciate that you had the guts to write it._________
-Matt
Red Bull has no earthly idea what "air racing" is.Comment
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