Is there a way to slow an electric plane down without doing damage. I know you can just stay off the throttle but what about cutting the motor speed in half and maybe picking up some longer flights. Would rather put something on the motor to make it run slower. Would like to hit trees at a slower speed!

don't know what you are flying, but if it has any kind of throttle control, just back off the throttle. it should run from nothing to full throttle, so you can set it where ever you like.

A smaller prop will de-power an electric plane. So will using a battery with one less cell.

change the prop and look for smaller trees.

Bigger diameter, less pitch prop.

The prop being smaller or bigger sounds good.I don't know how to buy a prop thats smaller.Is it pitch or diameter?Another problem is the plane has only one prop available so again back to voltage or mAh of battery.Maybe a resistor inline with motor? As for trees! It doesn't matter the size I'm on them FORGETABOUTIT! If I slow it down at least I could see the impact!

If you are flying one of those ready to fly pod and boom planes, slowing down the motor is not going to make the plane fly slower. The only way to achieve what you want is to make the plane lighter or increase the wing area.
These planes respond to an increase of airspeed by automatically pitching up resulting in a higher rate of climb which in turn keeps the airspeed down. Turn the motor off and the resulting loss of speed causes these planes to automatically dive which causes the airspeed to stay about the same. This is a natural charactoristic of trainers in general.

Best way to avoid hitting trees is to go somewhere that doesn't have trees. It's called a flying club and NOT a public park.

Still tooo many trees!

learn controlled flight.

Planes are not cars, you can't just fly at any speed you want. There is a minimum speed below which the plane will not stay in the air. Cut the power and the plane automatically goes into a shallow dive in order to keep that minimum airspeed. Depowering the motor is only going to turn that plane into a dog that won't climb.

If you want a real slow flyer, get a Slow Stik.

Maybe that Slow Stik is a good idea.Now I have to find where they are available.That just might be the ticket.Thanks Ron

What kind of plane are you currently flying?

Untill we know that we don't know what advice should be given.

A resistor in line with the engine will just burn more power in the form of heat causing less flying time only.