Dangair Posted at 2015-3-23 12:17
He had no GPS so setting home point would be impossible. He essentially took off without a home po ...

Hi dangair, so are there published procedures not to take off without GPS?

Tahoe_Ed Posted at 2015-3-23 11:01
Personally, I would not have taken off if I was not able to get a GPS lock in the outdoors.  That is ...

Thanks for your reply Tahoe. I will get this info to you tomorrow. The case has been opened in China via my place of purchase. They also have the flight logs. I am yet to hear anything though

As for your comments, can you assist in clearing these things up:

Yes, maybe I should not have taken off without GPS BUT the craft is designed to do this as per indoor flights.

IMU calibration performed approx 4 days prior.

I presumed that without GPS, manually setting home point would do nothing. SO when I lost RC signal, where would the aircraft have been going to?
What is the fail safe procedure for the aircraft in these specific circumstances, I would have thought it would go in to a hover then land

If it was in RTH mode, can you confirm that the aircraft is supposed to climb vertically to its pre set RTH altitude then proceed. Mine took of rapidly at 30 to 45 degrees whilst climbing.

Dangair Posted at 2015-3-23 12:22
But, it is a model aircraft and he didn't intend to harm anything. So we should find a solution to t ...

Points taken dangair but are there any procedures for the inspire that specify not to take off without GPS??  If there are, I will add them to my checklist. And yes, this is not a real helicopter!

Wolfman Posted at 2015-3-23 18:14
Thanks for your reply Tahoe. I will get this info to you tomorrow. The case has been opened in Chi ...

If I am flying indoors, there is no chance of acquiring GPS lock.  However, unless you were in straight ATTI mode, not P-GPS the GPS signal could have been acquired and potentially the home point set somewhere in space.  RTH is what ever you set in the App.  In your circumstance I would have either been in ATTI only or set the RTH to hover.  If you touch the sticks in v.16 or v.17 while the craft is ascending you can interrupt the ascent and cause the Inspire to head directly to the Home Point.  

Again this is all speculation and until the Flight Log is reviewed it is meaningless.  I look forward to your information.

Wolfman, the point I'm trying to get out there is this... the gps function is a redundant safety in the event of signal loss. It is presumed that indoor flight will be not furthe than 100 yards ie a stadium with the roof closed. So signal loss would be unlikely though not impossible. For outdoor flight gps is there primarily as a safety for long range flight and to stabilize in less than ideal conditions. By electing to fly sans GPS you effectively remove the safety. To answer your question about where it would have been going? that's a mystery. It may have headed in a straight line in the attitude it was left in, or as Ed suggested it may have set it's home point in flight, but there is no safety procedure beyond yelling LOOK OUT or HEADS UP! if you have lost both. She is a runaway train OZZY style.  

Dangair Posted at 2015-3-24 01:03
Wolfman, the point I'm trying to get out there is this... the gps function is a redundant safety in  ...

Too many strange things here Dangair to speculate until the information on the logs are revealed.

When it performed the "I am out of here in a hurry " manoeuvre, it was virtually stationery 3m in front of me so no chance of it continuing with any of its momentum in ATTI.  It powered up and made the decision to go "somewhere" after losing rc signal.
Totally agree with you points on the safety feature of the GPS but it is still designed to fly in manual without GPS.

RC Signal loss also occurred with the aircraft right in front of me which is strange in itself and hard to understand.

Tahoe_Ed Posted at 2015-3-24 00:49
If I am flying indoors, there is no chance of acquiring GPS lock.  However, unless you were in str ...

Thanks Tahoe ed, will pick up the file from the store and post.

When the rc signal was lost, it immediately speared off at around 30-45 degrees whilst climbing. I did try stick inputs but this was after it flew away, they were useless any way due to no rc signal.

Hopefully the answers are in the logs

Tahoe_Ed Posted at 2015-3-24 00:49
If I am flying indoors, there is no chance of acquiring GPS lock.  However, unless you were in str ...

Hi Tahoe Ed,

I have finally had a reply from DJI China:

"Your flight log is still under analyzing. Our engineer has analyzed it, while it seems a little bit abnormal.
We are forwarded your case to our R&D senior engineer"

Cannot seem to find a case number in any of the emails received. I did receive a request number "55139" for the upload of the flight data from the app.  Happy to send you the name of the person looking after the case at DJI China but not sure if you would like me to post it here, please advise. Thanks.

You know, I've stewed on this problem for a while. Obviously I don't have access to log files or the aircraft so it's only speculation. I wonder if the transmitter is defective? It almost sounds like one of the sticks may have a contact problem or the the mother board could be corrupt. Any hoo I know they will figure it out and you will be flying again soon. But my original comments still stand with regards to a pre flight and decision processes. As a pilot I know that a pre flight must be a full success or no go abort and re sort.

Dangair Posted at 2015-3-24 11:46
You know, I've stewed on this problem for a while. Obviously I don't have access to log files or the ...

Hopefully the results from the logs will not be far off dangair.  

With NO GPS, aircraft status was "SAFE TO FLY ATTI NO GPS" If the Inspire is not designed to fly without GPS then surely we should be advised as such. Whilst GPS is the best case scenario, it is still designed to fly without it dangair.
I followed my pre flight procedures and advised observers accordingly. Having GPS is certainly not a no go scenario, especially if you are experienced in flying manually. With the number of GPS drop outs noted in the forums since the last update, then there would not be much flying performed with the Inspire if you take this approach.

I agree to a point. I have not experienced a lack of GPS ever at the start of my flight, it always seems to happen a minute or so in. So my spidey senses would be tingling if I had a no gps warning at take off. But yeah what you describe is not a normal function, I'm totally with you on that.