Frustration

[macspite]

I had a day over at our vehicle compound, surrounded by trees so it felt calm though the tree limbs themselves were moving. I had sensibly? decided to not be tempted so left the 550 at home. Came back at 17:00, seemed calm in the sheltered area by the house so checked Chimet on the net - Chichester Bar Beacon, about 400 yds from me in the sea. 6 knots gusting 8.

Seemed ok flying conditions. I now know battery times and have set up telemetry and alarms for voltage plus a countdown timer on my Tx. Waited till 17:50 then drove to the beach car park a mile away where there is a big wide expanse of grass - no charge for parking after 18:00. Unloaded, put battery in 550, switched on transmitter, connected 550 battery. Got good GPS within 30 seconds.

So - wind quiet, charged battery, good GPS, no-one around. What could go wrong?  ::)

Nice clean take off and then - rotating like a disco glitter ball about once every second and a half. Put it down gently and killed the motors. Restarted and noticed the left rear (it';s set up as an I6) was reluctant to start. Tried to start again and it hesitated then spun up with the rest, no load. Tried a take off and same glitter ball rotation so put it back down. I';m quite pleased with my landings in the circumstances, both times gentle touch downs. 

Last time I had used the 550 was about a week ago due to winds since being stronger than my self imposed newbie limit preventing me from flying. What I had done was run it indoors, weighted down in order to get an idea of battery run time - in that instance everything seemed to run ok, all motors starting and stopping together and no odd noises.

I have had a quick look and nothing odd seems to have occurred - motor turs by hand ok, cabling from ESC to motor, ESC to controller and ESC to distribution board all seem fine.

I will take it apart tomorrow and use my spare motor and ESC unless someone has any bright ideas that might save me the hassle. Stock DJI motors and ESCs, Wookong controller.

But, on the other hand we got the engine of our 155mm howitzer running so today wasn';t all bad 

[SimonS]

Swap the motor with another one on that\s already on the multi.  If the problem moves with the motor then it';s the motor at fault.  If the problem stays on the same arm it';s the ESC.

[macspite]

Thank you!  Obvious when you think about it  :embarrassed- thanks for pointing that out for me, will save a bit of time tomorrow morning 

[macspite]

Further to the above ...

Motors swapped over, weighted down the hex and did an indoor run taking the battery down low - took 5400ma into a 5000maH lipo. Everything performed happily.
Today has been the first day where winds were calm enough for my liking. Took the machine over to our vehicle compound and after working most of the day there pondered whether to go do to the other end of the runway where it is clear or do a quick test in the concrete, vehicles, trees and swamp surroundings of the compound.

Common sense lost and I did a quick (!:40) flight up and around. Rock steady and controllable, beautiful landing even though I say it myself. Then went down to the far end of the runway and the model flyers down there pointed me at a piece of waste ground well away from them. Used the remainder of the battery on a second flight, all good. Especially when hovering at 3 feet above the perimeter track held up a queue of aero modellers cars.

Changed batteries, another flight. Toward the end of it set RTH and it came back then the suspect motor almost stopped, recovered, almost stopped ...
Changed back to atti and brought it down. Checked all the motors and the naughty one seemed to be running rather hotter than the others - they were warm, the susoect one was hot. So now changed for a spare and will see what happens tomorrow - though I have an exam at 13:00 so depending on how that goes depends on whether I will be flying 

[SimonS]

Well, at least it looks like it is the motor rather than the ESC.  Nice to nail it down.