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Word I heard was the new geared engine was giving them fits. They then swapped motors to the "old style" non geared/last years type, I suspect to probably to get the A/C qualified in time.
It broke. I was in the hangar tonight and they told me the new gearbox "lasted 20 seconds." They whole idea was to try to slow down the prop tips and add more prop area if possible (hence the 4-blader and gearbox). They are really bummed and I know the fans share their disappointment.
Granted, it's only Thursday night, but for now they told me they have no plans to rip the motor back out and try something different.
_________
-Matt
Red Bull has no earthly idea what "air racing" is.
Well, that's a bummer. I'm always interested to see what that team can come up with, given that they're now competing with significantly newer airframes (NXTs) and those with a lot more engine (Thunder Mustangs, sadly not this year though).
But this also goes to the point of why its not just a matter of coming up with a new reduction gear for a Griffon, as is often suggested. Reduction gears for piston aircraft are *not* a simple deal, not nearly as simple as turbine gearboxes because of the power pulses of a piston engine.
But this also goes to the point of why its not just a matter of coming up with a new reduction gear for a Griffon, as is often suggested. Reduction gears for piston aircraft are *not* a simple deal, not nearly as simple as turbine gearboxes because of the power pulses of a piston engine.
ditto. torsional excitation cannot be taken lightly
anyone get any pics - before or after the engine was pulled?
how are they getting the airplane home? I thought I read that it showed up on a trailer? Or was that another project?
Anyone ask about next year? Is 33 done racing?
As some of the engine guys pointed out, the engine / gearbox / prop system dynamics is not to be taken lightly. And that may have been the problem. Was the "4-bladder" prop one of those white, plastic covered light weight wood props from Europe? while that would help the CG problem from such a heavy engine, that gearbox was probably not designed for such a low inerta prop. So the engine power pulses would slam the gear teeth back and forth, and either the teeth broke, or the quill shaft sheared from all the excitation. I recall that TCM was having field problems with starter gear drives breaking, and traced the problem to light-weight, low inertia props. So now if you want warranty coverage on your starter drive, you have to meet a min inertia value for the prop, which means aluminum blades.
But I hope they continue to try the geared engine. It is the most efficient power package for Sport Class racers. A big, slow turning prop is always more efficient than a short, fast turning one. Notice how well BT did, even before she was boosted? And for Sport Class trivia, an aerobatic, fixed gear airplane went from the 230's (in 2003) to the 290's the next year just from switching to a geared, turbo Continental (with an aluminum prop). I was hoping that Claypool made it again this year to see what else they could get from the engine and a cleaned up airframe, but as no times were posted, I'm guessing he was a no show.
Maybe next year will bring out some other geared engines. They will be the one to beat.
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