I have had my phantom 2 vision plus for about 4 weeks now, and have put in about 20 hours flying (and more in the simulator).
As I am awaiting a new ribbon cable for my camera/gimbal after an unfortunate drift-into-tree crash after losing GPS lock (I was concentrating on keeping my son's flying in frame, not flying the bird -- my mistake there), Ive had time to sit down and read about fly-aways. I didn't want to join any user forums until I had a chance to fly the thing, and enjoy it (which I have, immensely), as reading forums for products can be a scary and I didn't want to start off by reading about all the problems. Videos and manuals to learn the ropes, along with flying manual in the sim, development of preflight checklist, and patient practice with real flying.
As I got more familiar with things, I switched to NAS-M mode. All my skill building was so I would be able to fly a canyon after 2 weeks with the bird. All was a success - and other than almost running the thing outa juice while sitting gawking directly over a waterfall (got the warning, took control back and quickly landed), it was a great time, no damage, and nobody died ;-).
After that, it was on to distance testing. It was in the second distance test that I seemed to lose flight control at my outer limit (1600 ft !). The bird was out of sight, but the radar indication was that whenever I pushed forward on the stick, the radar would flop around. What the heck ? I threw it into home lock mode and dragged it more of the way back to me - I didn't trust RTH mode, as the bird needs to be able to point to fly home, and it wasn't doing that (at least my logic was that it needed to be able to point). Once I took control back, I descended and tested controls - all were fine. no further problem noted.
I had 2 batteries left, so I decided to wring the thing out with some aggressive maneuvering close-in, and 25 feet up. It started happening again - forward stick gives me left yaw only. Home-lock again, dragged it back (spinning), and landed it.
Took it home and hooked it up to the assistant, and immediately noticed something - the controls weren't calibrated. I had calibrated them, but only initially when the bird was in phantom mode. I switched back to phantom mode for initial testing, and the stick indicators were againe centered in the assistant software. I took it out and flew 3 batteries, with no issues, so now felt ok going back into NAS-M mode, and calibrated the controls. No similar issues since.
The moral of the story, and the reason Im posting is that ive never seen this mentioned in any flyaway prevention treatments.
When you switch to NAS-M, calibrate the controls fresh ! Might also do an IMU calibration for kicks, since ur there, and check everything else out.
I can imagine what may have happened if the calibration was further off, or if the throttle calibration was way off due to NAS-M switch without a recal.
Thanks for all the considered input on this thread. Flyaways scare the heck outa me. I really want to do FPV at a distance, and understand the risks and 'fail-safes'. The thought of losing my aircraft doesn't bother me as much as the possibility of where this thing could come down at a high rate of speed. Its not only enough to make me not fly FPV, but it has me considering not flying the thing at all around urban areas. My adrenalin certainly was pumping for all 4 of the distance tests I did, and the elevated risk factors accepted in going out of control range and re-acquiring were the nerve-wracking parts.
Speaking of which, on a couple of the flights I had FPV video freeze (home-lock and fail-safe got me home). I cleared the freeze by repowering the phone (?) - I don't think I powered off the bird before resetting the phone, although it was on the ground. It could be the phone perhaps, but Im more inclined to think that continued loss of sig, and reaquisition might introduce some issues on the fringes of signal integrity as seen by the receiver - if the control channel has any issue like that, then its a real scary thing (as if losing video while FPV isn't scary enough).
In any case, love flying the thing, but the novelty f flying around open fields, making the sun rise in the west and all that is wearing off - my original dream was FPV at distance - but in an urban setting, you could hurt someone. Sooner or later these things aren't new anymore, and will start to fail (motors perhaps). That leaves me with wilderness flying in FPV, more tame pursuits closer to home.
What these things need is an independently controlled chute pack. That would alleviate /most/ concerns of flying urban.
Sure there is always risk in flight - same as it ever was. As a few posters presented, all flying is mitigation of as much risk as possible.
Thanks again, and I hope my NAS-M tip helps someone out.
