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Old May 19, 2002, 09:58 AM
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in persuit of low wing loading
Gordon Johnson's Avatar
Boston, Mass
Joined May 2001
6,463 Posts
Jochen,
I'm still doing tests, which I should have complete details on my site early next week. But, from the M20-LV 6:1 and 5x2.7 prop it pulls about 0.77amp near the beginning of a motor run. So far I'm finding very little more thrust for the HV version of the M20 on LiPoly compared to NiMH, probably because it's more efficient and doesn't pull as many amps. For the LV E-Charger version, I'm seeing between 4% and 20% more thrust (4% occuring at 1/2 minute and 20% occuring at 7 minutes) with the LiPoly compared to NiMH, presumably because these cells can deliver somewhat more amps. This may be the real win combination -- more power and less weight.

I'm also discovering that when letting the charger take the time to get a full charge, that the volts right before putting a load on are peaking at about 4.30v. A motor run from this very "full" charge puts out slightly more thrust. However, the quicker not quite full charge of about 66 minutes charge obtains about 4.15v and almost as much thrust. So, for flying the one hour charge is probably sufficient to be able to get back out there and fly.

So far the charging time is the only downside I can see to these cells.

Graham, I found out Matt had used one of these cells after I had mine on order and was dreaming of loops. When I heard he had used these cells and done a loop, I contacted Matt and verified they were the same cells. Then I began thinking thinking the loop wasn't a dream after all, but a definite possibility with the right plane.
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Last edited by Gordon Johnson; May 19, 2002 at 03:52 PM.
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