Futaba 12Z Problem

[rcalbuquerque]

I have been flying Futaba for 25 years with never a problem until now.
I recently lost my new 100cc Aeroworks YAC with a BME 110 motor and All Hitec 5955TG servos. During the first flight of the day I began practicing the Basic IMAC sequence when I lost all control of the plane and calmly watched as it went in full throttle. It never went into fail safe. I sent in the radio to Futaba service and after a few weeks it came back with the following repairs:New parts installed
4 (1) 71-CRCW04023301FT 3.3K OHM RES
4 (10 2M41A05802 ST-52 STICK ENCODER
service notes:We changed the Stick pots and checked radio thoroughly

I called Futaba Service to check what caused the crash and was told the Stick pots were bad and that could most likly was the cause.
I am out $1300 for the Plane
$675 to BME to have the motor repaired
$160 for damaged batteries and switches
$200 for a 28/10 carbon prop and spinner.
I'm not one to complain or bash a product but I am out alot of money and am looking for some advice on how to proceed.
I have had everything repaired and aquired a new plane but franly I'm scared to use this radio now.
Lou S.

[Dantley]

Is your radio new? Was this the first plane you've used it in? I've been using a 14mz for over a year and I have lost a 50cc GP Ultimate because of lock-out due to the sensitivity of the receiver.

For my 100cc plane, I put in a Power Expander and I have zero problems in the air.

[loop an roll]

when was the last time you sent the radio in to have it ckecked out.

[paffy]

That explanation doesn't make much sense.

After the crash, were you able to confirm/deny that the Transmitter sticks were actually not moving any control surfaces ?

Each pot and the associated electronics is independent inside the transmitter all the way to the ADC multiplexer. You can estimate the likelyhood of four of them crapping out exactly at the same time yourself.....

Did you have electronic ignition kill switch installed ? If you did, the motor should have quit in case your receiver loses power.

P.

[madmax]

Hi Louis, welcome to FG! In an effort to not insight a riot, and discuss possible scenarios more, the name of this thread has been changed. Thanks for understanding.

[Judge]

Some observations:

1 - You "calmly" watched your plane go in??

2 - It took weeks to get repaired??

3 - It went in at full throttle? Did it glitch first (did you command the full throttle setting), or did it just stop responding?

4 - Did it work after the crash? What battery system were you using? What was the post crash voltage? Did anything work after the crash??

And have you taken this up with anyone at Hobbico except the un-named person you spoke with on the phone?? If not, why not and why post here before you have tried to talk with Hobbico further??

Just curious.

And BTW - it is a "YAK" not a "YAC".

[Mithrandir]

Defective pots I would think to cause glitching on that channel...not a full "System Lights Out" like you describe.

Did you program FS to low throttle... I think it defaults to last command unless you set it to low throttle....

Sounds like a battery power failure to me... (I am not a Elec Tech... just a 30 year RC Dork)....

Sorry for the loss of your plane... good idea to have a sacrificial model just for testing new radio gear....

[Judge]

Just as an FYI- Folks at the service center tell me that whenever they get a radio in and they find, or suspect, a bad pot in the 12Z of 14MZ, that they simply replace ALL the pots. It does NOT mean that the pots were all bad. Making this complete loss of control even more interesting.

[rcalbuquerque]

Radio was about 8 months old with about 75 to 100 flights between a funtana 90 and the aeroworks yac.
Batteries were two fresh 5 cell 1950 nmh sub c sanyo packs and two new Electrodynamics heavy duty switches .Both packs had over 6.3 volts after crash.
Basicly the plane started rolling and would not respond to any comands after about 1 minute into the flight. There were several top IMAC pilots who were present during the crash. I am just as stunned as anyone I have never had any problems with Futaba. I thought at first I had Radio Interferance but the plane did not go into failsafe so I couldn't tell untill I sent the radio in. One of my friends at the field said don't bother sending the radio in cause it will just come back ok butI sent it in just to be sure. I am not trying to start something here just trying to get some help or advice.I have been flying for over 25 years and know how to fly a plane.

[Mithrandir]

I really would suggest a more thorough investigation... as assuming the problem fixed via Defective Pots... could lead to another mishap should the pots NOT be the first cause.

Really sounds more like an electrical power failure...

Give the remains more scrutiny if you can.....

[rcalbuquerque]

Mithrandir
When the pots go bad the radio doesen't go into failsafe cause the signal is still good just mixed up . When I got the radio back from service last week I installed everything in my new plane...powered up then turned the transmitter off ...throttle whent to low...Failsafe working ok .My Yac never went into failsafe.
Please this has never happened to me before nor have I heard of it happening to anyone else. Should I just shut up and take the loss. Should I call Hobbico. I have been silent up to today cause I just wanted to be sure what happened.I Have the service receipts to back up my story. I just called Futaba service today cause this has been eating at me for a few weeks and feel like something should be done.

[Darklighter]

I always hate hearing about this kind of misfortune. I also use a Futaba 12z and have a lot of money invested in my Comp Arf Yak. (The most expensive plane I have had in 30 years of flying) I have been using the 12z for about a year at about 5-10 flights a week and no problems yet.

Sorry to hear about your loss.