Just going over this loss again. Looking over google earth/maps to try and figure out where to begin a search. Distances out here are still deceiving to me and I'm doubting my observations as I look at the overheads again.
Here's an overhead view:
The green blob is the area I had planned to be flying in. I really didn't plan on going very far at all today, just some playing around far enough for safety but close enough to recover the crashes easily since I was half expecting something to go wrong mechanically with the new motors. The lighter green dot is where we were standing when I took off.
The blue trace is what I remember seeing the flight do. There's a section missing to the north over the river where I lost visual with it. And it ends a bit before the area where I think I lost visual with it as it got less and less clear what it was doing as it got that far away.
The yellow line is from where I was standing when I lost visual and where I thought it looked like it was at the time I lost it. Though I keep questioning if it may have been further south now that I see things on the map. The red circle is the area my initial first guess puts it coming down in.
But seeing this on the map and measuring distances I'm now wondering if it really was as far west as I thought it was when I lost it. It may have actually been further north and not as far west. In which case there's a VERY good chance it went for a swim.
The corner in the park will be easy to search so I'll start there in the morning. The area on the north side of the river would be easy to search but is harder to get to so I'll save it for last, I also consider it the least likely area for it to have come down. I'll contact the RV Park to make sure it didn't land there. The area to the west of the RV Park will be hardest to access but is the area I most suspect it would have gone down in. That field is some kind of fieldgrass about waist high...if it landed there it probably didn't even break a prop....but would probably get "harvested" rather than rescued. But it should also be obvious where it is if it is in that field as I've crashed into similar fields before and they leave a big enough depression that you can spot them fairly easily.
One thought I had was maybe when the RX failsafe killed signal it dropped and AUX low and that triggered a condition. I know I had thought about setting up a potential failsafe that way - but looking at my last saved config (and I haven't messed with this setup in awhile) it appears AUX going low should result in everything going off leaving it in just basic acro mode. If it had locked in MID then it would be in angle mode. If it had locked high then it would be in GPS hold, alt hold, head lock, and GPS home all at the same time...which would probably not be good. But none of the failsafes were setup to fail high. The screen shot from here still reflects the settings I was using:
http://forum.flitetest.com/showthread.php?8795-DW-tricopter-V-2-5&p=98635&viewfull=1#post98635
I was in horizon at the time of the crash, AUX1 was high all the others were mid. I had tested AUX2 high for alt/pos hold since I had been tuning that lately and wondered how it worked on the new motors. But I wasn't using it at the time of the flyaway.
I'm thinking more and more it was a failure of my openLRS rx. It was on top so when the quad landed upside down from the prop coming off it landed right on the openLRS which is just held in place with a rubber band (still haven't figured out a better way) and a bit of 1/8" foam between it and the arduino for padding. Then another 1/8" of foam under the arduino. I gave the openLRS a once over but most of the bits worth checking aren't visible and nothing jumped out at me and it still responded to radio tests so I figured it was good...but maybe something had been damaged in the crash and came loose.
There had been a little bit of frame damage in the first crash which I had forgotten about in the "excitement" of the flyaway. The rear right top knuckle plate had cracked and the portion of the rear arm on that side was bent in slightly. The wood hadn't cracked yet...but it was no longer straight. It still seemed together enough I felt ok flying on it, I've flown this frame in much worse shape. But maybe it contributed some extra vibrations that threw something off...
I really hadn't expected this to become such a long distance flight. I really thought I had my bases covered and my failsafes configured so I couldn't have a flyaway. I had done everything I could think of to test it except a full TX off test which just seemed reckless.
Only thing that's making sense to me is the RX locking and sending the same inputs but even that seems highly unlikely.
