Hi guys, working on trying to power a R/C plane with solor panels. I need to know how many MA the motor takes, the battery is a 500mah and it will fly for around 20 minutes. Thanks.

 

Here is the plane,

http://www.ebay.com/itm/Original-Wl...e=STRK:MEBIDX:IT&_trksid=p2055119.m1438.l2649

 

Here is the plane...

http://www.ebay.com/itm/Original-Wl...e=STRK:MEBIDX:IT&_trksid=p2055119.m1438.l2649

 

Sorry I posted that twice

 

Are you expecting to power the plane without a battery?

 

No I am going to have the solor panels charge the battery, but I want them to charge the battery as fast as the motor is draining it.

 

What is the solar panel spec?

 

I need to know how many MA the motor takes, the battery is a 500mah and it will fly for around 20 minutes.

From that the motor apparently takes about 1.5A.

 

The airplane is a cheap very lightweight low powered one. It weighs only 58 grams with its battery and a review shows that it is so underpowered that it can barely fly. 20 minutes is 1/3rd of an hour so it draws about 1500mA! Its battery weighs about 12 grams but a 3.5V solar panel that delivers 1500mA will weigh way too much.

A review shows replacing its motor. It has 3 tiny motors joined together and have a gearbox. Like most cheap small RC airplanes the motors have brushes that soon wear out.

My RC airplanes weigh 80 grams and use a powerful brushless, gearless motor that lasts forever. They fly maneuvers for 6 minutes with a 280mAh/7.4V battery therefore they draw about 2.8A but not at full power continuously.

 

What is the solar panel spec?

Here is the specs on the panels I was gonna use, but if you know of any better ones let me know, thanks...

http://www.ebay.com/itm/2pcs-1-5W-1...d=221080821565&_trksid=p2141725.c100338.m3726

 

The airplane is a cheap very lightweight low powered one. It weighs only 58 grams with its battery and a review shows that it is so underpowered that it can barely fly. 20 minutes is 1/3rd of an hour so it draws about 1500mA! Its battery weighs about 12 grams but a 3.5V solar panel that delivers 1500mA will weigh way too much.

A review shows replacing its motor. It has 3 tiny motors joined together and have a gearbox. Like most cheap small RC airplanes the motors have brushes that soon wear out.

My RC airplanes weigh 80 grams and use a powerful brushless, gearless motor that lasts forever. They fly maneuvers for 6 minutes with a 280mAh/7.4V battery therefore they draw about 2.8A but not at full power continuously.

How much can your planes carry?

 

The airplane uses a Li-PO battery that is 3.7V and its motor uses 1.5A. That is 3.7V x 1.5A= 5.55W.
The 1.5W solar panel is 12V which is much too high and a current of only 1.5W/12V= 0.125A which is much too low.
Since the power from the solar panel is much too low then 4 of them are needed (paralleled) and a buck converter can reduce the voltage and increase the current.

But 4 solar panels weigh 4 x 64 grams which is 256 grams and the airplane can barely lift its 12 grams battery. It will not fly trying to carry that much weight (plus the weight of its battery plus the weight of a buck converter).

If the solar panel charges the battery with the same amount of current that the motor uses then the battery does nothing.

 

Not to mention the fact that you can only put panels on fuselage. Unless you have a film solar panel. If you alter the shape of the wing...she won't fly.

You will also have to pay attention to weight distribution and center of gravity.

And even with panels.....you still need a battery.

 

I am sorry to say this is most likely not possible. If the solar cell had enough power to charge the battery while the plane flies, then there would be no need for a battery at all. The fact the flying time is 25 minutes (which hardly ever is) and the charging time is 40 to 60 minutes clearly states there is no way to charge the battery fast enough.

Solar cells are super inefficient. When they can somehow truly extract most of the light energy, then something like this may be approachable. I don't think we are there yet...