Thread: FES - Take 2
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Old November 2nd 14, 04:45 PM posted to rec.aviation.soaring
jfitch
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Default FES - Take 2

On Sunday, November 2, 2014 7:22:41 AM UTC-8, kirk.stant wrote:
On Sunday, November 2, 2014 1:21:54 AM UTC-5, Paul B wrote:

Agreed, my response was an explanation why the SZD-55 driver had lower break off points than the motor / sustainers gliders, which I think Kirk was questioning.

Paul


And again, why would an FES (or jet, or even a classic "turbo") sustainer have a higher break off point than a pure glider? You would still look for lift until it became obvious that the day was over, then while setting up a pattern, fire up the sustainer and either fly away, or land - and the drag of an extended sustainer (and the workload of starting it) is nowhere near that of an SLS.

So what penalty, other than the drag of the FES system (not present in classic "turbos" or jets) does a sustainer suffer over a pure glider? Weight? Does that mean that skinny pilots should be penalized over fat (ahem, "mature") pilots? Especially in "no-ballast" contests, the difference in wingloading is more affected by the "beer ballast" that the presence or lack of a sustainer!

Kirk
LS6 "66"
Happy at my 8psf dry wingloading!
I'll have another Stag, please...


To understand why an auxiliary powered glider has a higher break off point you would need to fly one for awhile. The pilot workload when low is significantly increased by the decisions and mechanics of the power plant. Perhaps less so for the FES system, but still there. Off field landings at a strange site are not normally accompanied by a feeling that you have all the time and can afford all the distraction in the world.