lwatson

My Feedback: (2)

Just put together a Phat Larry from NorthEast Sailplanes. It is identical to the Acro Phat accept it has a flat airfoil. It comes with a Geared 480, but it seems really heavy compared to the construction. In fact it is so nose heavy, I am going to need to put the battery at the trailing edge of the wing to get this thing to balance.

I was wondering if there was a lighter motor that might power this thing. I am flying at a mile high so I really need the power, but I don't need true 3d performance. Brushless is OK, if it really has a better power to weight ratio.

Thanks for your help
Larry

Dr Kiwi

Hi Larry - you don't say what sort of g/box you have on your 480.
If its a black MPJ 4:1 nylon, your motor + g/box weight is probably around 134g, if you have an MPJ all-metal planetary, around 152g. I reckon your best bet is to go with an AXI 2808/20 which weighs in at just 96g, complete with Graupner mount and prop adaptor. My test bed figures suggest that on 8 KAN 950's with a 10x7 prop on it you'll get about 14oz thrust @ 10A , and over 20oz thrust @ 20A draw. Even allowing for your losses due to altitude, with an all-up weight of about 18oz, those sort of thrust figures should enable Phat Larry to go vertical, or even hang on the prop on full song!

Cheers, Phil

lwatson

My Feedback: (2)

Thanks Phil,
I knew there had to be a lighter way.