For those out there that are waiting for a real constant speed unit for
electric VP props, there is one in the pipeline for next year: I kicked off
a project with a friend of mine (an electronics engineer) and we have just
completed a "test" unit, to be flown in January.
Electric CSU's are not as simple as you might imagine - factors such
as relay response times and hub cycle times (ie. from fine to coarse) all
throw a spanner in the works, and to refine our design, we have been forced
to build a multi-variable unit that will fly for no more than an hour or two
as a data gatherer: after that, we shall build a "proper" ECSU -probably a
digital one as it won't drift out of calibration and hopefully have them for
sale late '99. It appears that they will be usable on most prop/engine
combinations with minor tweaks: the first probably being Rotax/NSI and
Rotax/Arplast. Cost has yet to be worked out, but the target is under =A3500.
The control format we are looking at currently is manual pitch
change -as they are now- with an "rpm capture button". After that we shall
be investigating something a bit more sophisticated -perhaps with automatic
mode selection linked to MAP -something along the lines of TO/Ldg and Cruise
settings....
All the best,
Miles
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