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Old Dec 13, 2012, 01:06 AM
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ScratchCrasher
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Greece, Makedonia Thraki, Thessaloniki
Joined Jun 2008
584 Posts
Nice story jimbo24, and great closing line

This brings up a subject that I have been thinking about....

From the OSD manual:
"Minimum Ground Spd(0 disable): If the plane's ground speed (as reported by the GPS) is below this speed, and you are at or below the specified
cruise altitude window, the "climb" throttle setting will be used."

This was implemented in an attempt to make RTH operate at higher wind speeds. However, shouldn't there be a further improvement by using "cruise" throttle setting when the plane is above cruise altitude and its speed is lower than minimum ground speed, and manipulate the elevator to control (reduce) altitude? Bacause, if throttle is cut when above crouse altitude, then at high altitude and in a strong headwind the RTH is not effective, since it may read negative GPS speed (thinks its travelling the wrong way) and make a turn when it is not needed. With an airframe that floats well, and if RTH is triggered at high altitude (and a strong thrermal in the worst case scenario) it could take a long time for the plane to fall to cruise altitude even with motor off. In the meantime it could have travelled a significant distance further away from home...

Comments please?

Reards,
Stavros
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