Thread: Mini-HowTo How to choose a power system
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Old Sep 11, 2007, 01:39 AM
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Melbourne Australia
Joined Jun 2006
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Hi Dave,

What you say would seem correct to me. I say seem because I'm not an expert and someone is sure to correct me. Having flown some of my models with various pitch props of the same diameter I notice the following with a higher pitch:

It takes longer for the model to accelerate to take off speed.

Top speed of the model is higher.

The prop creates a higher load and the power system runs at a higher amperage.

The model takes a lot longer to decelerate for landing. I expect because the higher pitch prop creates a lot less drag when spinning freely when the throttle is closed.

I am envious! I wish I could afford to go solar too. Is this your first RC plane?

As far as stall speed goes, even if you can calculate the stall speed you don't have an airspeed indicator like in a real aeroplane so you have to judge it. The stall will of course be at a lower ground speed when flying into the wind too, so it is common to practice stalling any new model nice and high up to get a feel of the stall characteristics and speed so you have plenty of altitude to recover if something nasty happens. Some aeroplanes have nasty tip stalling tendencies at low speed, which means a wing will drop suddenly and the model will go into a spin. Most trainers won't have this problem if the centre of gravity is in the right place.

Are you in Perth? If so you should go and fly with Smokin Beaver!
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