I posted once disagreeing with something in his "How to Cool your Wankel book" and he never posted it just sent me a private email telling me I was wrong. I think he's a little overly proud of that book and thinks it's the only way to cool an engine. And of course he believes that the Wankel is the embodiment of mechanical perfection, and nothing can be said against it. There was one guy from a car magazine I think that had done a head to head test of an RX8 against a BMW and was citing all the figures about fuel efficiency he had from the test and Paul didn't have anything real to say against it he just kept telling the guy he was wrong. I had the mental picture of a little kid plugging his ears and shaking his head, yelling "nope, nope, nope".I must also say I have been unceremoniously kicked-off Paul's site, but for the life of me I'm not sure why. Needless to say there are many who have suffered the same fate who wear it as a badge of honour - personally it doesn't worry me one way or another, but I still have many good friends from that period, some still on there for any possible developments/revelations.
I can say however as far as Aviation developments of the engine (for general Aviation use), my contacts seem to be well ahead of Paul attempts - but I wish him well for the record attempt.
Paul has been gushing about how effective the radiator is (it's 2 dodge truck rads combined in a cross counter flow arrangement) to the point that they might not need the spraybar water. Although I give him credit for the fact that it's doing well I've never seen one of his renderings of a rotary engine setup that allows any air to actually circulate around the engine, and if there were some, then that air had been preheated by a trip through a heat exchanger before it got to the engine block itself, and wouldn't be able to carry much heat away. His drawings usually show a duct running from the intake to the exchanger and the exchanger being vented directly out the side of the cowl.Here is Peter Garrisons comments cut and pasted from his site:
The oddest thing about the airplane is that it has no cowling. The engine, with all of its plumbing, air and oil radiators and general clutter is left out in the breeze. The reasoning is that at 90 kias parasite drag will be a minor factor. Actually, this is not quite true; at best rate of climb speed, which is bound to be close to the best L/D speed, parasite drag is half the total drag. At any rate, I did some calculations, making various unfounded assumptions about the drag contribution of the engine, and found an impact of several hundred feet a minute. I did take into account the fact that a cowling would add weight at the same time as it reduced drag. The cooling drag, of course, would still be there.
I don't have the emails any more but I'm pretty sure Paul said something about doing 120 kts straight up.The way I see it, if the anticipated climb rate is 12,000 fpm, then he should calculate the parasitic drag at a speed higher than 90 kts because 12,000 fpm nearly 120 kts by itself. If the climb is anything less than vertical, the total airspeed will be even higher.
Paul said something to that effect since I've been aware of the project and repeated it in the latest set of emails after the crow hops.With 650 HP, a decent propeller, and 1,200 lbs. gross weight, it should be capable of vertical flight at lower altitudes.
I've tried a few internet searches to find radiator areas on either the spitfire or the mustang since they both had the Merlin, could you supply a link to that info? I'm kinda interested in putting that in the discussion about the radiator since the topic keeps coming up and would like hard data before i do.With more rad volume than a 1600hp Spitfire, he's doing nothing impressive with cooling 650hp here either. It's another inefficient, high drag solution but in this application, that may not matter.
That's something to think about. Imagine if you'd built a little 3 HP 4-stroke water-cooled engine. You'd taken steps to assure very little air cooling occurred at the cylinder head and block, but you had only a tiny water radiator of less than 3 cu inch volume (about 2/3 the volume of a deck of cards), and an even smaller radiator for the engine oil. It's amazing that there's enough surface area in there to provide the needed heat exchange for a 3HP engine running at full capacity. It would seem more plausible if the heat exchanger was 1mm thick and the LxW of a sheet of paper, but that's not the packing ratio used by the "big boys."Doing a little math here the Merlin 66 put out 1720 hp so that's .81 cu in of radiator capacity/ hp (assuming your 1400 cu in estimation is correct) and .72 cu in rad/ hp on the TTC project.
Ross has a really good point. Gearboxes are designed around torque and speed. I doubt the capable folks at Bell came up with a box grossly overbuilt for their engine just in case someone would want to do something hugely different 70 years later.I'm not sure why a Bell 47 gearbox (280hp) would be so overbuilt to be able to handle 1000hp but it might handle 650hp for the few minutes needed here.
Glad they are still in one piece.Well they nearly burned the plane up along with the pilot. I guess a mechanic didn't reinstall a piece of safety wire on one of the injectors and it came loose and sprayed fuel on the engine. Given the lack of talk about damage I'm guessing they caught it pretty quick and damage is minimal. But Paul is talking about what a crappy job racing beat did of setting up the system and it sounds like maybe he'll be building a new fuel rail for it.