Hi All,

Is there a way of calculating nicad drain times?

I am building a 2ch glider with 2 standard servos & a 1100 Mah nicad. I just want to know roughly how long would the nicad last before it needs to be recharged?

Many thanks.

Ian.

depends how much they are moved while flying as the drain goes up and down.I've flown gliders with 550 mah packs stayed up 45 minutes straight with out problem .stopped due to a stiff neck.

Two or three hours at a minimum.

Hi again,

Thanks for both of your replies.

I have just purchased an onboard battery monitor for my glider, but its helpful to have an estimate on how long these nicads hold a charge for.

Thanks again.

Ian.

Holding a charge and drain due to load are two different things.

I use a 1200 6 volt pack with 5 servos and typicaly will get 5 ten minute flights before I consider a re-charge. I have a voltwatch on board that allows me to keep an eye on the battery condition before and after each flight. When it begins to get out of the green and into the yellow while I move the sticks, it's time to recharge. That usually happens after my fifth flight.

Your setup is more ideal because you won't have an engine vibrating which causes the servos to gitter and consume more current. And, you only have two servos. You will definitely be able to get at least an hour, and as suggested, as much as two. And, again, as mentioned, your neck will hurt long before you have to land because of your battery.
CGr.

If you are talking about a typical rudder elevator thermal glider running std analogue servos you should get at least 3 hours with a pack that size.