Looking for some feedback on a electric conversion

I was given a few kits from some local guys here after a really bad crash testing my AP over the weekend. What I am looking for is help in determining if the motors and batteries I already have would work for either or both of the new kits I have. I have been trying to read and find electric conversions that are the same or similar and seems that everyone has their own ideas on what works so would love to get some ideas flowing before I just jump in and ruin something.

Kit 1: Sig Kadet Senior kit, not the ARF with ailerons

Kit 2: Great Planes PT-60 Trainer

What I have linked to below I already have sitting around collecting dust but would rather buy something new if it would be better suited than just making these work if they are not what I am after.

So here is what I was going to use for my engine:
http://www.hobbycity.com/hobbycity/s...idProduct=4914 this was my first choice but I also have another motor laying around thats bigger

choice 2:
http://www.hobbycity.com/hobbycity/s..._580Kv_/_1580w

Battery:
3s 20c 2200 mah x 2
was going to run 2 of these together to give me a 6s2p2200-20c setup, Imay need a different battery config to give me the in air time Idesire. Though I do not think this will be a strong enough battery setup for giving me my desired flight time.

ESC:
http://www.hobbycity.com/hobbycity/s...idProduct=4315
its a hextronik 80a

I am not to sure what size props to try running, I would like to get asclose to or over 30 minutes if possible as my flying time. Also it willbe taking up roughly 3-4lbs in extra gear, probably closer to the 4eventually. Thanks for any help or incite into this, as I do not wantto just try the motors and end up with the plane crashing. I welcomeany and all suggestions for this so I can have my best chance at doingit right the first time. I am not set on which one to use, both are not built kits as they sit right now, so ideally I would like to just pick the one that would be the easiest for my first kit build and can carry the payload amount I want and also get the flying time I seek.

Thanks again

That first motor you list will be just fine, along with the 6s voltage. You may need to reduce the prop size a little to keep the amps to a safe level for those cells but so long as you don't fly around at full throttle the entire time they will be fine. With that pack you have about 900w available, more than enough to fly either of those aircraft but its unlikely you will get 30 minutes flight times, you may get close, say 15 to 20. You may find it very convenient to learn to fly around some with that pack, and get some larger ones on the way at the same time. Don't bother buying 40C cells, its pointless if your going for duration. For that motor any pack capacity in amps x the "C" rating of the cells equal a number over 60 is a waste in terms of "C" rating.

As a direct example 2.2 x 20 = 44, so you want to keep the amps below 44 with that pack. But lets say you get some 3300mAh 20C cells, they are good for 3.3 x 20 = 66 amps, the motor is only good for 60A for 60 seconds so they are a good match. Lets say you get some 40C instead = 3.3 x 40 = 120A, well all that means is your carrying around a battery that is heavier than it needs to be, 40C cells are heavier for the same capacity than 20C, cost more and do exactly nothing for you.

My fully 3D 72" Giles uses 14c cells, 7800mAh x 10S and pulls over 100A on freshly charged warms cells - you don't need 40C cells for 3D, much less for a trainer going for duration. Get your full load amps rating out of capacity, not "C" rating. Please link the actual packs used so I can check their real ratings.

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Paul G. November 14, 2010 at 10:04pm

That first motor you list will be just fine, along with the 6s voltage. You may need to reduce the prop size a little to keep the amps to a safe level for those cells but so long as you don't fly around at full throttle the entire time they will be fine. With that pack you have about 900w available, more than enough to fly either of those aircraft but its unlikely you will get 30 minutes flight times, you may get close, say 15 to 20. You may find it very convenient to learn to fly around some with that pack, and get some larger ones on the way at the same time. Don't bother buying 40C cells, its pointless if your going for duration. For that motor any pack capacity in amps x the "C" rating of the cells equal a number over 60 is a waste in terms of "C" rating.

As a direct example 2.2 x 20 = 44, so you want to keep the amps below 44 with that pack. But lets say you get some 3300mAh 20C cells, they are good for 3.3 x 20 = 66 amps, the motor is only good for 60A for 60 seconds so they are a good match. Lets say you get some 40C instead = 3.3 x 40 = 120A, well all that means is your carrying around a battery that is heavier than it needs to be, 40C cells are heavier for the same capacity than 20C, cost more and do exactly nothing for you.

My fully 3D 72" Giles uses 14c cells, 7800mAh x 10S and pulls over 100A on freshly charged warms cells - you don't need 40C cells for 3D, much less for a trainer going for duration. Get your full load amps rating out of capacity, not "C" rating. Please link the actual packs used so I can check their real ratings.
Stephen Wuest November 14, 2010 at 6:37pm

I have flown the next size down Kadet - the SIG Seniorita. I used a Monster Power 15 and 3S or 4S LiPos. I think that I used an 11x8" prop. Less than 400 watts to the prop.

It was underpowered, but flew nicely. However, the wing was very heavy, and it turned poorly with the ailerons.
The tricycle gear also caused me trouble on grass fields. I have come to prefer tail draggers on grass.

You'll need 80-100 watts to the prop for each pound of plane, for sport flying. If your plane is 6lb, you only need about 480 watts to the prop. The 1580 watt motor is way too big. A HOT motor for a 5lb plane would be about 900 watts. Even with a 900 watt motor, you will probably be stretched to get 10 minutes of flying time. (I had a 900 watt headsuprc motor, running 2 parallel 4S 2200mAh batteries. It put 850 watts to the prop, and pulled 58A at full speed. It put out close to 7lbs of thrust with a 15" prop.)

The speed controller sounds big enough.

As far as batteries go, you may need 40C batteries to hook them in series. 20C is a bit low, and you may find them really heating up, in series.

I hope that this information may help a bit.

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Looking for some feedback on a electric conversion

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