Feasible conversion or Not?
 

Hi Guy's,

I'm trying to determine if conversion of an 88" Extreme Flight Yak to Electric would be a feasible proposition. The motors and ESC seem to be a very feasible option but flight time is questionable.

I think the following would be appropriate:

Motor: AXI 5345/14 Gold Line
ESC: CC HV-85 (I have One not sure if it's up to task) or CC HV-110 or Jeti Spin 99 Opto
Battery: Zippy 5000mAh?[&:]

My concern is available run time on the 5000 mAh LiPo pack. Going by one of the online calculators @ 75A and 75% discharge I would have a flight time of 3 minutes. I feel that this figure is unrealistic as you're not at full throttle all the time.

Does anyone have any experience with such a set-up and what run time could realistically be achieved for 3D and aerobatic flight?

Regards
Jason.

RE: Feasible conversion or Not?
 

Jason,
sounds like a pretty good set-up. Zippy's aren't the best LiPos, but for the price they're pretty decent. Most calculators give a estimated cruise time as well as a WOT run time. Without going to my Calculator I would guess that you could expect flight times of around 8-10 minutes with good throttle management. That may sound short to you, but in the early days when lack of duration was a complaint by wet flyers I did a time check on eight or ten of them; average flight time - 9 minutes. Average "estimation" of flight time by the pilots -15 minutes!
Walt

RE: Feasible conversion or Not?
 

You might want to go for the lower Kv 5345/18. 12S1P 5000mAh, 22x10 prop at about 6100 RPM. The HV 85 is the best choice. Expect about 14lbs of thrust.

RE: Feasible conversion or Not?
 

Hi Walt and Dave,

Thanks for your help & responses guys.

If an 8 to 10 minute flight is possible then I'll be very happy. Battery technology will continue to improve over time so things could get better in the future.

I asked AXI directly what they thought and they said the same as you that the HV-85 would work but they couldn't guarantee it. I will use the HV-85 after all I already have it. AXI also recommended an APC 22 x 10E prop as the 24" prop would be too much for the motor. They also sent me the attached chart which is useful. AXI estimated 5 to 7.5 minutes flight time but it all depends on how you fly with your throttle management...

I'm not sure about 12S as I'll be flying an F3A electric ship later in the year and a 10S is perfect for that application. We shall see...

Some more things to think about but it looks to be very feasible.

Cheers
Jason.