Latest update on my issues, CS quickly got back to me and asked me to reset the ST16, then calibrate, bind and test fly the TH.
So I did a full reset (after copying all the files onto my computer first) and calibrated all the controls, then did the rebinding, and calibration of compass, accelerometer and gimbal in the usual way with no metal influences near and mobile phone turned off. When both of my batteries and the handset were fully charged, I went to the flying field (a local school sports field) and initially all seemed well.
After I switched on, I left the TH sitting on the ground for several minutes after the ST16 linked with it, because I have noticed on various blogs and sites that some people say that it takes several minutes for the satellite catalogues to download so it is safer not to lift straight off after doing updates, although I have noticed others do not subscribe to that view. But better to be safe than sorry, eh?
I then started motors and took off in a hover at about 4-5 feet for a minute or so and all seem to be ok, although the machine was a bit jumpier than I am used to. But it was controllable all the same and not really an issue. I then landed and let the motors tick over for a second or two before taking off again in order to do some lazy circuits and figure eights. About 150 feet horizontally from me, the TH suddenly shot up to 70-80 feet altitude from the 10-15 feet I was flying at, and started to shoot all over the sky although by that time I had let go of both sticks. Opposite stick seemed to do little at first so I put it into RTH to see what would happen as it was heading towards the school and road in a zig zag pattern. RTH had no effect that I could detect, and the throttle stick had no effect whatsoever so it stayed at about 70 feet altitude.
I put it back into angle mode, because by that time I thought it had probably lost GPS lock and shortly afterwards it suddenly went into a sort of hover but the motors were pulsing about once a second and the machine was shooting up 20-40 feet then dropping down again (I have not noticed anyone else reporting that sort of behaviour before). After what seemed like ages, but was probably only a few tens of seconds, I managed to position it over the centre of the field away from the road (while it was still pulsing up and down) and pulled the throttle stick back fully, but it took a long, long while to descend and finally land. Luckily, by the time it got down to about 20 feet, the pulsing had stopped, because I was worried it would smash into the ground on one of its downward pulses. It landed without falling over and I stopped the motors (and started breathing again!).
I decided there and then that I was not going to have another attempt because the likelihood was that I was going to have an accident, which at best would have resulted in damaging the aircraft and at worst injuring someone.
I am beginning to learn about the sorts of experiences that lots other people have described on the various forums including this one, and to be frank, they are scary! Other than one occasion in early October when the machine refused to land for several minutes, it has flown rock steady and I did not understand what other pilots were complaining about. Well I certainly know now….phew!
CS in the UK now want me to return the TH and ST16 to them because they want to get to the bottom of these issues. So it has been packaged up and will be on its way early next week. I have to say, CS has been very quick to respond to my problems, so here's hoping it can be sorted out relatively quickly.
Cheers everyone.
