Just delivered Inspire a few days ago. It took a while to get some other things sorted (the correct tablet, firmware, old password, etc) and finally yesterday I was ready for maiden flight. Everything worked as it should and through the day I took maybe 5-6 short flights each time coming inside looking at video and learning another piece of what I need to learn about this awesome aircraft.

At one point in the day the motors wouldnt start. I wasnt sure why and re-booted, and re-calibrated, and checked the flight mode (p-mode always so far), checked gps status etc, and the craft eventually came to life (after something must have changed) and I made another short flight.

This morning I was at my office for a while which has a spacious warhouse type interior and I thought Id try and start up inside and see how the aircraft responds with just the sensor technology, but I could not get the Inspire to start up. I tried everything I could, changing modes, re-boots, etc, nothing worked and I gave up. Later I decided to go look for an exterior location to try to do some small shots with the camera and Im having the same problem now outside, cant get the motors to start. Ive gone through everything now a dozen times, modes, calibration, re-boots, etc. The transmiter says Steadigreen connection, the picture from camera is clear on tablet, the center top window in pilot app say "safe to fly, GPS" and the motors will NOT start. Ive tried the auto take off, and manual start.... nothing.

Calibration for the first 10 times today seems to have worked fine, but the last 2-3 times Ive tried I got a warning "IMU error, re-calibrate" ... then I try to re-calibrate as I have now done may times with no issues, and now it wont re-calibrate. I tried moving to a different spot further from metal etc, and still the same. But it was actually the same spot outside my home that ive successfuly recaliberated a few times yesterday.

Im stumped... need help, any ideas?

I gave it a break and went through the process a few more times and then randomly the motors started. I took the opportunity to fly around a bit till the batt ran down. Went inside checked the video put batts on charge. Loaded everything back up, went back out and went through start process and calibrate the same as I've done and again no motor start. Maybe its an intermitent bug, but I don't know. Guess Ill try firmware re-install.

Firmware reinstall on the tx fixed this issue for me. Hope it works for you.

I have noticed that with a different stick modes, the stick positions for starting the motors changes also...2 cents

Rutch, Ive tried many different stick positions also.
Clint, and tips on firmware re-install for tx?  TX not responding as manual says it should for install.

Often I will turn on the DJI Inspire and everything looks good and ready to fly. When I try to fly either with auto takeoff or with sticks down to center, I will get 5 rapid red LED flashes on the back of the inspire and it won't start the motors. If i turn the inspire off and back on a few times it seems to finally work. I have no idea why it won't take off.

Make sure you do not move the craft while booting. You should have the craft on a level surface as well.

Hi Blade, yes that what Ive done every time, still very intermittent leaning towards not working.
Still no response from DJI.

Not sure what other's are experiencing, but I intermittently have the same problem.  I simply unlock motors from the app, and then  ....  they start.

I had similar problem...which I "solved" by putting both sticks, not in the CLC position but in the lower opposite corners.

Sorry for my delay! We need the flight log where you unlock the motors but failed. First pls send a mail to autumn.a@dji.com with the post link. I'll send you methods to access the flight log.
Then pls try again >> power up your aircraft, put the sticks to unlock the motors, then power off the aircraft. Extract this log then send to me.
Thanks.

Wanna know the status. Is it fixed now?

May I ask what Pilot App you are using and if you've ever used the Flight Simulator Mode? Probably not your issue but its happened to me several times. I use flight simulator and then the next day try to fly and I suspect that the iOS app is a bit confused about what mode it is in. As a matter of fact I am positive that it is one cause of now several starting issues I deal with from time to time.

And now an update to this response.  I had a starting issue again but this time I had not used simulator at all recently. Something is going on with that iOS app.  It is not just the flight simulator but once again I can fix it by restarting things like the ipad itself.  I don't always get the 'you cannot take off in flight simulator mode', either.  So now I just have to wait and think about what is going on here. Suffice it to say I am confident it is the app.

Dan

DJI-Autumn Posted at 2015-1-30 18:19
Wanna know the status. Is it fixed now?

Hi, yes. I found another thread with talking about IMU caliberation and gave that I go, and my problem went away.  thanks for asking.

Dccam Posted at 2015-2-1 19:05
Hi, yes. I found another thread with talking about IMU caliberation and gave that I go, and my pro ...

Great

Could you elaborate on the IMU calibration?  I've seen it in the app but not sure what it's for or when to do it.  Thanks.

jkelly2900.att Posted at 2015-2-2 04:53
Could you elaborate on the IMU calibration?  I've seen it in the app but not sure what it's for or w ...

Jkelly,

To calibrate your IMU select Mode then Advanced Settings, then Sensors as you must have already done.  Then scroll to the bottom and you will see three choices under Calibrate.  'Check IMU' (useless, IMHO), 'Basic' and 'Advanced'.   Select Advanced and it will do the rest for you.  The advanced calibration will be followed by a Basic calibration. It may on occasion tell you its too hot to do and to turn off everything for a few minutes and then try again.   It is pretty easy to do.  I am doing it quite often now.  If you haven't flown much or maybe even if you have, you may want to do it before each flight.  IMO the thing that may govern your frequency of calibration will be your ability to detect subtle changes in stability and control.

The IMU calibration refines values for your Gyroscope, your Accelerometer and Magnetometer.  The IMU itself is what the aircraft's navigation system derives orientation and other data from so that it can compensate for changes in position.  This is a constant and dynamic process during flight. One problem with IMU/navigation system relationship is that it tends to lose its compensation ability and self awareness.  The navigation system begins to not know the truth about what is going on.  That's when you can have issues with drift.   Recalibrating the IMU can help prevent this.

daninperth Posted at 2015-2-2 15:36
Jkelly,

To calibrate your IMU select Mode then Advanced Settings, then Sensors as you must have al ...

Thanks for the explanation.  

clintbarton.ema Posted at 2015-1-25 07:02
Firmware reinstall on the tx fixed this issue for me. Hope it works for you.

How did you make Firmware reinstall????