short flight time help

Me too

Gear mesh was suggested....I'm going for crap lipo.

Originally posted by Sooty Check if motor and ESC are hot at end of flight. Heat = power loss. You should be running a motor as efficiently as possible - not an aerial heater. I have extended my 450 flight times by using a lower KV motor, smaller pinion, and lower head speed. The motor runs at full throttle so that ESC is not bleeding off speed and producing heat in its place. The motor comes down with the outer can cold to touch and ESC is barely warm. Much more efficient than running a big motor and pinion throttled back. Same principles apply to 500 size. All the other suggestion above are relevant also. Everything should have a running-free feel about it.

That's absolute right, mine 500 with same 3000 20c battery, Turnigy 85A esc, H3126 1300kv motor and 12 pinion can hover 13 minutes to 3.4v per cell, motor is cool and esc slightly warm.

Edited by spilVentinjsh - 30/Jun/2011 at 5:02pm

I would stick with an 80amp Plush esc. I use these throughout the whole range and have never had any problems with them. 

+1 on what Sooty and Mattyc said about partial throttle. Some ESC's are worse than others at low throttle.

If you don't have a wattmeter, you can estimate your average amp draw if you time your flights and your charger tells you how many mah it puts back into the battery.

For example, lets say you used 80% of your battery capacity, so the charger put back 2400mah, for a 3 minute flight. That would imply an average current draw of 60/3 x 2400/1000 = 48 amps. That seems quite high to me - the average power is over 1000 watts, whereas I would expect a 500 to use about 300 watts in a hover at normal headspeeds.

You might have a combination of things, such as a bad pack and a setup that's asking too much of the pack.

Bear in mind that Align recommend a maximum headspeed of about 2650rpm for the 500. The main blade bolts are only 3mm, same as on a 450. With an 1800kv motor on 6s, you shouldn't use more than about an 11t pinion, unless you're using governor mode, in which case you might run to 12t.

As you increase headspeed, the power consumption goes up by about a cube factor - so doubling the headspeed results in almost 8 times the power. You therefore need to strike a balance between the responsiveness you're looking for and the flight duration. Remember that responsiveness at lower head speeds can be improved with larger control throws and lighter paddles.