Hot, High and Heavy? [Archive]

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Hognose

11-18-2003, 03:36 PM

Anyone have any suggestion for a gyro that would work in a hot, high and heavy environment? Say -- 7-9000 ft MSL launch and recovery sites, need to pass over 14,000 ft rocks, need to lift ~450 lb while doing it (counting fuel). cheers -=K=-

mceagle

11-18-2003, 09:04 PM

Hog-nose, The gyro would have to be kept very light, have a very efficient rotor and would probably need to be powered by a 914 or one of the larger two strokes. It should be quite possible though. I cannot recommend any particular brand though because I am not familiar with all the different Gyros available in the USA.

donshoebridge

11-18-2003, 10:06 PM

Hogmose, I'm not sure how many seats you need, but that is going to make a big difference.  Typically, the higher, heavier, and hotter you go, the more rotor diameter and engine power you need.  In this case, I would suggest that you look at something like a SparrowHawk, a 2-place Dominator, or a 2-place AirCommand.  To get the extra lifting capacity, a longer hub bar can be used on any of these to increase the rotor diameter.  As for power, the SparrowHawk would have the most of these three, with the AirCommand and the Dominator being about equal. The Dominator and AirCommand have a wider selection of powerplants that can be utilized, where the SparrowHawk requires something quite a bit larger, usually an automotive conversion. I'm sure someone else will provide some additional input very soon.  Hope this helps.

r.coplen

11-19-2003, 02:21 AM

Hognose, Where can you find good landing and takeoff sites at those altitudes.   You will need oxygen when you are going much above 10,000 feet.  I would expect you would be in some severe wind conditions.  I don't think if this is a good idea in a light gyroplane. Randy Coplen

Udi

11-19-2003, 03:42 AM

The Hawk 4 would be a good candidate.  As soon as it becomes certified, I mean. Other than that, you may want to consider a turbocharged modified RAF.  But, as Randy mentioned, you would need a fairly long runway at this altitude (not for the Hawk 4, as it can make jump-take-offs). It sounds to me that what you really need is a helicopter. Udi

gyromike

11-19-2003, 05:02 AM

How about *a Little Wing? http://www.littlewingautogyro.com/specs.html 20,000+ feet with a 914 Turbo. Real cross-country capability. Enclosed cabin. http://www.littlewingautogyro.com/transcon.html Oh yeah, welcome aboard Kevin! I've read most of your excellent posts on R.A.H. Hope to read more.

rehler

11-20-2003, 03:00 AM

Hot, High and Heavy. What is needed is a lot of dependable horsepower and light weight (not heavy).  The Rotax 914 may be the answer.  And add lightness!

Hognose

11-23-2003, 05:15 PM

Thanks for the replies. Aeromedical concerns are covered. I'm looking for something with better performance that what's currently projected for use (PPC with a reeealy large canopy). Motor's not that big an issue. The Soobs used in RAFs and AAI's Sparrowhawk can be adapted to this altitude no problem, even normally aspirated (as long as they're the EFI ones). You can drive a Subaru you bought in LA to Pike's Peak and it works. The Little Wing is probably not in the running simply because time is an issue. I watched Ron fly it at Mentone (the rotec powered one) and it is simply beautiful, at rest or aloft. I had been thinking a 2-place machine already (operated one-up at altitude). The nice thing about the PPC is I can teach anyone to fly it in about ten minutes. All you can teach in a gyro in ten minutes is "Darwin 101," and I'm not sufficiently skilled yet to solo it, let alone instruct. In the end the training thing might send me to the PPG/PPC. I do think a gyro designed for the task would be the perfect solution, but time and budget are real concerns. As far as increasing rotor diameter is concerned, yeah one can do that, but diminishing returns lurk there. I agree with Ken that weight reduction is key. Duane Hunn operates an RAF at normal altitudes and has instructed, I'm told, a 350lb student. That indicates significant surplus lift. Duane has a larger than standard motor in his RAF. Any books on gyro aero that have reasonably credible models/numbers? I can't afford to hire the University of Glasgow, but I'm hoping they wrote stuff down.... cheers -=K=-