I believe the duty cycle found on the T62 was exactly the reason why it was deemed fine as an APU, but not as a powerplant. An APU running at two or three fixed rpm settings i.e. Idle/Nill load/Max Load will never see a resonance point between any of those settings for any time at all. Not so if your using that engine as your helicopter powerplant, and thats where trouble occurs. I believe that more than one person has died from putting a Solar T62 into a homebuilt fixed wing, as it's just not designed for the duty cycle of flying through rain etc. Your taking effectively a single design point device, as most APU's are, and asking them to work as a broad band device without, as far as I'm aware, any re-engineering at all.
If I was looking for a turbine for a homebuilt, I'd rather fit an Isotov GTD-350, which is under 300 pounds dry weight and is an excellent, modern design and giving 400 shp. Then you will at least get factory support - if you try as a homebuilder to get factory support from Sundstrand, who now own the rights to the T62, you will get a legal letter telling you to stop what your doing and to never contact them again. They know what your looking to use that engine for, and don't like it at all.
Good luck if thats your thing though. Your IMHO a brave man indeed.
Last edited by Chukkablade; 24th Oct 2007 at 20:52.
Reason: spelling is dreadfull after a bottle of merlot!