Signal loss.
Set-up on TREX-470
HW 60A V4
Spirit Pro B-surface
2 Lemon sats
4 Kst DS215 servos
Stock motor
Two nice flights. Now the issue. On the 3rd flight I spooled up and saw a tiny tail twitch then signal loss. No control at all, no fail safe. Just sitting there at full spool.Was able to see red lights on both sats. Seemed stable on the ground so we just let it sit until the battery died. At about 13 minutes I was able to grab it and pull the battery out. Took it back to bench and checked all settings, I re bound and set failsafe again, pulled the pinion and blades and spooled it up trying to get it to do the same thing again but everything seemed to work fine. So we put it back together and went to the flight line. I turned throttle hold on and off a few times and it worked as it should. I then spooled it up and right before take off a tiny tail twitch and no control. This time it didnt go so well, after about 4 minutes the wind got it and it chicken danced till death. I am not sure of all the damage, but the kicker is both tail twitches would have been at the instant or just before i touched pitch stick. Any ideas what could of caused it, we think its a load issue of some sort. Just dont know if its a spirit issue and maybe the esc is browning out. Also a side note. went with spirit after getting the update bug ffrom Brain/Ikon. ANY IDEAS

Hi,

that is very sad you are having such troubles.

Could you let me know if this helicopter was flying previously? (with no previous troubles)
Is the belt tight enough? This is the only thing (big static discharges) that could normally cause such troubles. At the time of spoolup, lift off and landing they are usually the strongest.
Aren't the satellites placed near the tail boom?

If any odd behavior happen, I highly recommend to never try it again in the air until the problem is found and resolved. Any issue that occur once, will occur again sooner or later.

I am sure we will find the issue and all will be good.

If you are able to repair the model, it would be good just to spin the helicopter with no blades. In this way no damage will happen. You could be able to observe a servo glitches, satellite flashing and similar issues.

_________________
Spirit System developer

It has flown fine before the Brain update issue. Yes it flew 2 times that morning before the issues. . Once by me and once by my buddy Trey who is a Hobbywing and Spirit guy. He checked all settings before the 1st flight. Then again after the 1st issue. It is a TORQUE TUBE 470. Now i had problems with the lastest Brain updates thats why i changed to Spirit. Im sure he will chime in soon. I will try to rebuild it and try a spool up without blades , but maybe try to weight blade grips with some fender washers. i just dont know where to start on the promblem.

Thomas,

I helped walk Skip through the setup and then check his setting in the morning of his Spirit maiden. I have now setup several Spirits and this is the second person I have helped convert after having such a positive experience myself.

Skip is running a torque tube tail so I am not sure that the static issue would be there. Also, the first 2 flights after setup were flawless.

After the issue the first time, we rebound and then did a successful range check with his DX6G3 and spun up with the pinion removed, no issues.

The only thing I can think of is the Spirit browning out due to lack of BEC power. Would it exhibit this behavior of loosing all control and just sitting there at last known control (including throttle curve) if it browned out?

I was in fact one of the weirdest things I have seen. We even tried to invoke the failsafe (which included throttle to the hold position) by turning the TX off, nothing worked.

Thank you for the details.

If it is torque tube driven, then we can exclude a static issue.

HobbyWing ESC has quite good BEC. Did you performed BEC test just to make sure it is all ok?

Could you describe your wiring, please? Is RPM lead connected?
The unit could freeze only in some major hardware issue or if BEC voltage is under 1.8V which could trigger uncertain condition or reboot the unit.
Satellites are using the same power supply as unit, so it is important they are OK too. If you have a spare satellite cables it could add some confidence as they are very fragile.
In a rare cases the cables could short +/- randomly (during vibrations) and then it could cause such troubles.
Lastly we can't unfortunately exclude issue in the unit, which would be very sad (we can send you other for comparison so it is with you on friday).

What I recommend is to:
1. Not to change anything on the model, but try to run helicopter with blades off until the problem appear - it is important to replicate it.
2. Then try to change/replace just one thing and try point 1 again, until it will disappear.

I guess that a certain level of vibrations are required in order to replicate the problem.

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Spirit System developer

Have tried 2 full batteries and no luck getting it to lose signal. have wiggled sats wires and other wires. Did notice that plugs going into Spirit are very loose. Noticed it on the build. then again today. Not sure if its machined larger then other units but lots of play in plug area. Rpm wire is not connected. Im really thinking it doesnt have enough load with out blades to replicate it. Also did try turning off radio well it was spooled up. Fail safe kicked in perfectly which it didnt the other 2 times. Im at a lose was what to do next. I dont have blades ordered yet so no way to test with any type of load.

Our units are compatible also with Futaba plugs that are of little bit different shape (wider), so normal connectors might feel loose. For this reason it is good to use a hot glue or double sided tape to secure every connector.

Tommorow we can ship you other unit so you can swap it (today we have holiday in our country).

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Spirit System developer

Ok, Thanks.

Got it changed out, reset everything. Had a couple buddies check it and it flew fine. thank for your help.