Dear Sir,
I will try to describe you the problem I have with my unit, so as you may help me.
I have a spirit 2 on a trex 450 and a spirit pro on a trex 600 esp converted to fbl with belt driven tail and a futaba 10.
Two weeks ago, I took the 600esp to fly three sets of batteries. It flew great except for some tail kicks and minor delayed tail corrections that I noticed in some occasions.
After I finished checked the heli if there was anything wrong with that.
I found out that the tail belt was very loose, although the weekend before, I tightened properly when I went to fly.
I supposed that it happened because the quite big temperature difference between the two weekends.
When I returned home I wrote a notice what should I repair before the next flight.
That was the belt that needed tightening and the pirouette optimization that I decided to reduce it from 180 to 170 (because some head oscillations when hovering before landing).
So next weekend before I go to fly the heli I made these changes (I tightened the belt by extending the boom by about 0.5 to 1mm).
When I went to take off, I altered the pitch but the pitch was moving from the lower position to about half of it range.
I tried to check the movements and the elevator did not correspond at all.
Anyway I left to go home.
The next weekend (it was last weekend) I connected the gyro to the software to see if I can find something.
I saw at the servos bar that the pitch bar was moving from -138% at lower stick to -38% at maximum stick and the elevator tab was steady at -138% and did not move at all, whatever input I made at the transmitter (forgive me for any mistakes, I am from Greece).
As I did not find any mistakes I decided to just upgrade the firmware to the latest edition (I had the previous I think or the pre-previous one).
I did so, after installing the latest software as needed and after the installation, everything worked properly.
I just had to make some corrections (changed pitch end points in my tx and pitch range and tail limits in software).
So I went to fly.
Before fly I checked the movements of the servos, the reactions of the tail and the swash and the corrections of the gyro, both cyclic and tail and everything worked as they should.
When I spooled up, and the heli become light on the skids, it started to act strangely and give itself cyclic input so I had to immediately turn it off, just before it crash (and I think it did not correspond to my inputs but I am not really sure about that).
I checked again the connections, the inputs, the corrections and when on ground everything corresponded as it should.
I tried one more time to take off and once again the heli after being light, tried to crash, so again I returned home.
I fly the spirit pro since 2014 and the spirit 2 almost since it came out and have never faced something like that, so I do not know what may be wrong.
I am sorry for the big, tiring post, I just want to show the situation in details.
If anyone has any suggestion is very welcomed.
Thank you.
Spyridon

I had trex 600esp and for me Have you had any mechanical problems and I'm sure the vibrations they have reached high levels
check the gear in the tail box the teeth detach from the axis and it runs in circles.
so the tail no longer worked.
especially the white and gray gears

Thank you for the reply.
I did not have mechanical problems, however i will make a check on the parts you mentioned.

anyway, since you crashed, send the spirit to zexx86 and he'll see if it needs fixing or not.
mechanical problem or not, send the spirit and have it checked. some advice buy spirit gt or spirit gtr.
but do the math if you spend 20 dollars and 20 dollars for two shipments, go to the spirit shop and buy a spirit gt or gtr, I did it and it works great, the spirit gt or gtr is really good. It has automatic recovery and saves the helicopter on its own without you pushing anything
200 dollar about

Hello,

first from all I would like to ask what Receiver connection you are using?
The first problem you are talking about looks like a buffer pack incompatibility issue. Possibly if you are using buffer pack battery then it was discharged too much if your model was unused for long time.
Do you use any?

Kicks that are visible at the tail are in 99% result of electrostatic discharges caused by a wrong belt tension/bad grounding. It is quite common problem when model is unused for a longer time as the remaining belt powder inside the boom becomes dry and ackquire some more dust. If you are using standard receiver connection (PWM) then you can be almost certain it is caused by this.
These kicks are happening also at basically all other channels and can result in a crash sooner or later. PWM wiring is the most prone for this, but you can quickly find that this problem is happening and can resolve it before it will evolve in more serious problem.

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Spirit System developer

Why is there a mode to dump on the ground electrostatic discharges?
because if there is a method I use it on my helicopter

I dont understand your question unfortunately. There is no special mode, because similar problems could happen if for example there is gasser model with a spark from ignition being transfered to the rest of the electronics. Or just by loose cables.

Any random jittering or kicks are usually distinct phenomenon that are caused by electrostatic discharges coming from belt (if it is belt driven model) or HV ignition (if it is gasser). If using a digital protocol then with the most of them you can see receiver signal was lost or corrupted.

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Spirit System developer

Thank you for the advices.
Because of my work I did not have the time to make the repairs needed.
However, I disassembled the tail with the boom and cleaned it thoroughly, as there had been developed in the inside of it, a thick protective film of silicon grease, silicon oil and a lot of dust, all mixed together.
I also cleaned the belt from the same mix of dirt, applied silicon oil and changed the bearings from the tail box that, although they were not shot, they had developed some play (in the near future I will replace them with new ones, with tighter tolerances).
So there had been both vibrations because of the tail shaft play and a lot of dirt in the boom and the belt.
Something that I cannot understand: At the trex 450, I had 3 or 4 times cases of static discharge in the past, so I have it grounded.
At the 600 (I have it since 2008 heavily modified) most of the years I have it belted and I never had even once, a case of static discharge (so, I have not dealt with grounding it).
At the weekend I will finish the service and the setup, I will try it and I will let you know the result.
Thank you very much for the contribution.
Have a nice evening.
Spyridon

Unfortunately it cannot fly.
Although I set it up again from the beginning and extinguished any vibrations, when I went to fly, on the ground everything was as it should be.
I took of and flew for about a minute at 1 to 2 meters hight, observing the heli behaviour and it seemed that everything was fine.
Some seconds later the heli slowly made a perfect piro flip on its own. I tried to gain control but it slowly kept flying away and started making piro flips.
I did another two slow perfect piroflips without losing or gaining height, but as it was still flying away, I switched the throttle hold resulting in panic auto and a quite heavy landing.
Anyway, it seems that at the first time, when the belt was very loose, it resulted in a static discharge that maybe caused some malfunction to the unit.
So, I have decided to take the spirit 2 from the trex 450 and install it at the 600esp, as it is more fun to fly and send the spirit pro to Mr Thomas to make a diagnosis and if possible, repair it.
I would like to ask one more question. Can I make backup files with the settings of the two different spirit units and load at the spirit 2 the file from the pro,
so I make the setup easier (and if and when receive the repaired spirit pro, load the old settings from the file and be almost ready to fly)?
Finally, I would like to thank you for the suggestions, because the all helped me to find mechanical issues (vibrations and not good bearings that I would still used them and static issues and be more careful with the tightness of the belt).
Have a nice night to all.
Spyridon

the backup of a unit and restore to another is working flawlessly - i've done it many time when migrating from Spirit II > RS > GT/GTR! just check the result anyhow to be sure on the new unit... like directions/swash level/0°/6°/limits etc. especially as there is a suspicion of a problem with the pro unit, you cannot be 100% sure the backup does not contain any bad data (even it should not . but better safe than sorry)

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cheers
Michael