Guys,

Had a weird problem at the field yesterday.  I was flying my Electric Yak and in the air whenever I give any two inputs at the same time to my Rudder / Elevator / Ailerons, then my motor drops power and ultimately cuts off!!

There is absolutely no mixing done in my Tx.  The motor has a separate 4s 3300 mAh Lipo fully charged connected to it through a very reliable 60A Dualsky ESC.  The 2.4Ghz Futaba 7 channel Rx has a 1300 mAh 3s Lipo connected to it through a Dualsky UBEC.

I would have lost my plane twice.  It tracked fine during takeoff and the intial run was smooth but when turning, I give elevator and aileron inputs and then the motor dropped power and cut off even though I was at half throttle, and the plane stalled.. Lucky to have recovered it and landed it off the tarmac on the grass!!  This happened twice and the second time, the plane toppled over after landing on the grass and the canopy had a crack!!

While testing on the ground after the two crashes, I followed the below procedure..

1. Connected everything as usual and throttled up.  Smooth power delivery and the motor was acting perfectly normal
2. Gave it elevator input, still fine.  Gave it aileron input (without elevator) and no prob.  Tried rudder input and was fine.
3. Now when I give both elevator and rudder together, the motor started slowing down and then I tried juggling the throttle and no response and the motor quit even when I was at half throttle.. All the other control surfaces were perfectly normal.
4. Tried changing the flight pack.  No use.
5. Tried changing the Rx pack with another Lipo.  No use.
6. Now comes another weird part.  Removed the Lipo/UBEC and connected a direct 6V NiCd pack to the Rx.  The motor did not even arm.  It just kept beeping continously.  Tried a 4.8V NiCd pack and still the same thing.
7.  Put in the Lipo / BEC and tried again now.  THe problem stated in the steps 1,2 and 3 repeated itself.  Got really fed up and packed up!!

I am really stumped because even if the servos are acting up the motor should not quit as it runs on a separate pack.

Someone please give me some suggestions!  The next thing I am about to try is changing the Rx and trying!


All information on my setup can be found at,

http://www.indiarc.com/forum/index.php?topic=2124.0


- Chan

does your ESC have an inbuilt BEC along with it? if so have you disconnect the positive wire that goes to the receiver ?

and at what voltage is your BEC set at 5 or 6 volts, please remove the positive wire from the connector plug which goes to

the receiver and tape it to the wire and then see if you still have problems and don't worry about power to the ESC as the

built in BEC will handle its needs 

this is the best i can think of 

sahil

some thing like this(see the picture to get an idea about positive wire disconnecting) i still think your problem has to do something with current or voltage

Hmm    Try resetting the ESC programming (or make sure the ESC programming is valid for your setup).  Especially the voltage cut off stuff. 

QuoteHmm    Try resetting the ESC programming (or make sure the ESC programming is valid for your setup).  Especially the voltage cut off stuff.

yes and also check whether your BEC is up to the task (handling power need of all the stuff together) !

sahil

Chan ,
I think the best way is elimination
I will  follow the following steps :
1) I think  Tx / receiver malfunction could be the most likely reason as the throttle is cutting off when other inputs are given , hence I feel there is  some problem with  channels mixing in the Tx/receiver .
2) If Tx/receiver is OK then the  next culprit could be the BEC powering the receiver
3) If both above are OK then the ESC  would be the next suspect . I doubt if the ESC will have a built in BEC as this modle has flown earlier without the problem

My view is 90 % this is a Tx/receiver problem.
I think the only option is to keep eliminating problems 1 by 1  starting with the Radio as that is where the confusion is.

BTW  did you try  the Glow prop by any chance ?



sai

Thanks guys.. Would try troubleshooting one by one and would post my findings.  Thanks.

I still have not tried the glow prop on it!! I have the electric 13x4 prop.

- Chan

I suspect the ESC. Replace the ESC and see if the problem is still.
--Rao

hi chan

were you able to solve the problem ?

sahil

Hi Sahil,

Thanks for asking!! I was not able to sit and debug it still.. Started work on the VPP and completed the maiden today.  Since I had sold my Spektrum, I had to pull out the FASST Rx from the Yak and put it onto my VPP Katana!!  Would be looking into it only next week sometime!

- Chan

how was katana flying

oh okay, yes how did the flight go .

would post the details in the katana thread! uploading the video now! give me about an hour. Overall it was good but not so great as I had grossly underestimated the weight of the plane!! Should go in for a model half its weight now!!  Anyways details would follow in the VPP thread!

- Chan