Working on a hexa build and can't seem to get it off the ground...literally. Here are the build specs.
ST800 Bumblebee hexa frame
Hobby Mate 40-amp ESCs
APM 2.6 running most recent AC 3.1 f/w version
3DR power dist board
Tarot 320 KV motors
15x5.5 CF props
2x 5S 5000mAh Turnigy LiPo
Total takeoff weight approx 3500g
Radios calibrated, good GPS, etc...
I have attached a couple of LOG files to this post if someone would help review them. I have found a couple of parameters that seem suspect to me. APM is getting a 1963ms signal from CH3, but only feeding 1200-1400ms to the ESCs. The THR_MAX parameter is set at 80 and the TRIM_THROTTLE parameter is set at 60. I have not messed with either of these settings; they are the default settings from several F/W uploads. Are these settings defaulting with a zero omitted? The THR_MAX parameter on the AC page says it should range from 800 to 1000.
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UPDATE:
Well, the change in the THR_MAX parameter (from 80 to 1000) definitely helped, but there's still a problem. Either the two front (3 and 5) motors are weak, the 3/5 ESCs are bad, or there is something else going on. It REALLY tries to get off the ground, but the rear comes up first and the thing tips front and right. I checked the CG along the pitch axis and it seemed fine. I tried adding a little pitch up trim into the radio and that had no effect at all. I re-calibrated the 3/5 ESCs with no effect. Total AUW is well under 3500g without the camera and gimbal. It REALLY wants to get flying.
I do have a new set of motors on the way just in case. I ordered a set of T-Motor 400kv Navigator MT4014-400 series motors. If these Tarot 320kv motors don't do the trick, maybe those will.
I'll download logs in the morning after I sleep off the several beers I have had. Time permitting, I'll post up a video of the flawed takeoff too for your viewing pleasure.
Seriously, any help here would be greatly appreciated.