I'm having some serious problems with my Geolink. Yesterday, I ran into a very dangerous problem. I took off and climbed with Stabi and Geolink features disabled. Once I got to a safe altitude, I engaged both Stabi and Geolink altitude limit. I flew a few laps around the field and everything appeared to be working. So I decided to try RTH. Before I took off, I had set a new RTH position. I watched the lights on the Geolink and the Spirit and they behaved correctly. When I engaged the RTH feature the heli began flying away from where it should have. So I disengaged the RTH feature and got the heli back to where I had good line of sight. That's when things got interesting. The heli seemed to freeze and it acted like I had position hold activated. The only feature I had enabled at the time was altitude limit. No amount of stick deflection moved the heli. This went on for about 30-60 seconds. All this time I was trying desperately to get the heli to move. Then, without warning, while I had the cyclic pressed fully forward, the heli responded. This flipped the heli over. I'm no where near being able to fly 3D so this scared the hell out of me. Luckily, altitude limit kicked in and kept the heli from crashing. I still had my throttle and pitch curves set at Normal. I've never even tried using Idleup 1 or 2. At this point the heli began moving up and down rather rapidly. As the altitude limit engaged, the heli would gain some altitude, but then fall rather rapidly until the cycle started over. At this point, I had Stabi disengaged. The only feature on was altitude limit which was keeping the heli from crashing. I tried desperately to get the heli to flip over so I could land, but no matter what I tried, I couldn't save it. This went on for 1-2 minutes, but it seemed like an eternity. At this point, I knew the battery was getting low so I went to Idelup 1 to try and flip it over, but it wouldn't budge. My last act of desperation was to disable altitude limit, but not being a 3D pilot, before I could respond, the heli crashed hard upside down.

The first time this happened, the heli locked up after disengaging RTH, but I was able to land safely. Needless to say, I'm scared as hell to keep using the Geolinks. Unfortunately, I went all in and bought 4 of these things.

My setup (before the heli exploded after hitting the ground at light speed while upside down ) was pretty straightforward. I had the Geolink mounted on the boom (Goblin 380). It was a minimum of 15cm from any servo or other electronics. I had magnetic canopy locks, but I removed them after the first RTH lockup incident so they were not on during this flight. Both the canopy button and stud were replaced with 3D printed alternatives. I was using the included 20cm cable that came with the unit. It was a straight run from the Geolink to the Spirit.

Sorry for the lengthy post. I wanted to provide as much detail as possible. Unfortunately, I was caught up in trying to save my precious heli, so some of the details are a bit fuzzy. I'm not sure where to go from here. I've attached the logs I was able to download from the units. Hopefully someone can tell me what's going on.

Sorry to hear this. Did you have any previous flights where the Geolink functions worked properly? In other words, did the loss of control and other issues suddenly start or were these your test flights?

These were the first test flights. I've had about 3 flights with it. All of them acted erratic.

Wow, that was scary! That is very scary not being in total control of the heli. If that were to happen to me, I would have switched to the lowest throttle speed I could. I would switch to normal mode and land the helicopter gently on the rotor head. That would have broke the least amount of parts. Maybe you wouldn't have broke any at all. That is very unfortunate this happened to you. I am having my own problems with the GEO link. I really hope Spirit fixes this and makes it awesome and reliable.

looking at the logfile I see a lot of receiver lost signals. that would scary me ? if there is no signal then of course I would expect that the heli is not under control. I would check the TX,RX and connections to make sure that all that is working

Erik

Yeah, I saw the receiver lost signals as well. Not sure why that would be. Like I mentioned, I flew around without any issues for the first minute or two. The heli was never more than 300m from me and when those receiver lost signals appeared, it was less than 100m away.

Not much to check at this point as the heli is torn apart. I wish the Spirit and Geolink provided more detailed logs. The logs appear to be very rudimentary. I work in IT and I'm used to seeing very detailed error logging. Maybe something they can work on in the future.

Hello,

thank you for the details. Sad to see you are having troubles.

I am afraid but on this particular model there are at least two different problems.
One is definitively issue with receiver signal transmission and other could be Compass calibration.

Was the model flying previously correctly? I mean if the model was flying reliably without usage of any special features.

Did you performed the Compass calibration procedure prior flying?

More dangerous is receiver signal loss. As you can see in the log the signal was lost for several seconds. At this moment the model can't be controlled at all because unit is not receiving any data from your radio.
This was very likely point when you lost control of the model. This event (Receiver signal lost) should never occur when flying. When this occur then Failsafe is triggered. So what you have programmed will be triggered at this time.

So you could theoretically activate also Position Hold if it is enabled in your settings.

There are two possibilities:

• Cable between radio and Spirit unit is very loose.
• Your model is equipped with belt and static discharges are hitting the electronics.

It is very important to find what is wrong otherwise the event will occur again. I would check all the cables carefully and possibly also antennas.

If you have more models and they are flying well, then you can at least exclude antenna issue in your radio.
Even if model is 10 meters near it could lost the signal. For example due to receiver antenna cut by a carbon frame. Or loose connector in the receiver (less likely).

Unfortunately there is no way how Spirit can figure out more details for logging. There are only few possibilities that are described in the manual for each event.

_________________
Spirit System developer

Compass was calibrated and verified working so that's not the issue. And the cable between the units was solid. Nothing was loose. What else would cause the RTH to perform poorly? I'll look into the receiver issues once it's reassembled.