Thats where the confusion is with this. I see some slight yaw at around the start of the video. Questions to be ansewered. 1. At what point in the video did the pilot get concerned with the Orientation? 2. When the copter started to yaw left was that commanded by the pilot prior to PH engagement? Origionally it was heading north then abruptly to the south 28 seconds later. 3. Was the pilot commanding pitch and roll prior to PH engagement?
I think Shaun painting a fairly acurate picture. The reason I lost orientation is because the copter started to rotate and come towards me (perhaps due to the wind??) I didn't command those movements. Maybe as I was descending it didn't have the power to correct what the wind was doing to it? The heavy roll (that you can see in the video) is what got me really nervous as I didn't command that. I didn't know if it was just my eyes that were getting tricked or if the copter was really flying at that angle (something I didn't like). I put on the GPS to try and stop the uncontrolled movement. I didn't put on Alt.Hold (perhaps should have) I guess we are never going to find out.. sigh.
1. at around 17 seconds 2. no 3. no, i was watching in awe as it was flying with a heavy roll and pitch .. wondering which direction was front was so that I could try and counter it.
Unfortunately it maybe impossible to figure out the precise cause of the mishap. Not sure if this is comfort or not, I can with reasonable certainty say it was not pilot induced. The uncommanded movements are coincidental with the data logger dropping off. That event suggest something malfunctioned in the NAV board. The fact that GPS was off during most of the incident suggests that was not a causal factor. Could the GPS being engaged last second contributed to a more exacerbated situation? Its hard to say with any certainty. I am fairly conifdent the crash would have happened regardless with it on or off. Now the question, was this a permanent failure of the system? Or was it in intermittent failure that occurred with the right conditions? If so, will it do it again? Whatever happened, there does not appear to be any warning signs prior to the chain of events. It looks like the system went abruptly off line. Those would be things to be considered when moving forward. If you plan on using the same avionincs it may be good to do a bunch of bench testing with several power cycles to see if it recreates itself on the ground. It could have been a onetime event or it could be a degrading component somewhere. As Gary mentioned there was some high solar activity, in fact we have been exposed to some solar activity from a very powerful Coronial Mass Ejection CME event. These events can actually screw with electronics in general not just GPS signals. So even without GPS in question could have caused a latchup error. Usually happens at high altitudes, but you are in Canada so you are a bit more exposed then someone like me living in the Southwest. Not saying at all that this was what happened. Most likely not. Big picture if you even think that the board could go bad again I would swap out those components. Remember if you will need to modify the FC to handle 5S batteries. Shaun
I am currently conducting a formal crash investigation involving a Cinestar8 with Flight Controller Hardware Version 2.2, Software 2.0a. There may be some similarities with your incident. We would need to discuss this off-line.
Thanks again for the thoughts Shaun. I'll let you all know what more I find out when I start piecing things back together.