Odd radio incident, Or not.

[Paul De Tourtoulon]

1 hour ago, Frank Day said:

Shame about the damage but tufty grass did well. Its a weird one.

 

Never buy a Futaba Tx, planes just fall from the sky!!!

Complete rubbish,,,

I have been flying and selling radios for years ( model shop) and Futaba for me were the best as far as quality and fiability.

[Cuban8]

My only observation is that it's quite a thing for both aileron servo outputs to twist on their splines by such a similar amount given the force needed to shift them as you tried.

Hopefully no repeat.

[Martin Harris - Moderator]

 

1 hour ago, Frank Day said:

Shame about the damage but tufty grass did well. Its a weird one.

 

Never buy a Futaba Tx, planes just fall from the sky!!!

 

9 minutes ago, Paul De Tourtoulon said:

Complete rubbish,,,

I have been flying and selling radios for years ( model shop) and Futaba for me were the best as far as quality and fiability.

 

Wasn’t Frank’s post intended as an ironic comment on those who quickly jump onto threads to condemn particular systems because of problems that may have been due to external influences?

[Rich Griff]

Thread drift !!!

 

🤓😁👍😠😭🥳🤣😎🤔😸

 

The culprit/reason for the unplanned arrival has been  identified, probably.

 

Radio failure was not the problem, probably...

 

"My" faith in futaba reinforced !!! It was never in doubt really 👍

 

Edited September 18 by Rich Griff

[Rich Griff]

However, lots of bells and whistles, more complexity, fiddle factor, buttonitice and " lack of old school mechanical set up" resulting in electronic trimming needed, by virtue of a complicated multi function, lots of switches computer tx, mmmmmmmmm.

 

Not sure what tx John used, but he did state I think, that he set up plane *old school * mechanically wise, the proper way ?

 

Will re read thread......later, burning sunshine on here.....

 

Have a great day.

[J D 8 - Moderator]

3 hours ago, Frank Day said:

Shame about the damage but tufty grass did well. Its a weird one.

 

Never buy a Futaba Tx, planes just fall from the sky!!!

Been using Futaba since late 70's, Only issue I have ever had that was an actual radio issue and not dumb programing or batt problem was with my first set an M series who's rudder pot gave up. Sorted by Ripmax and set still works today.

[J D 8 - Moderator]

1 hour ago, Cuban8 said:

My only observation is that it's quite a thing for both aileron servo outputs to twist on their splines by such a similar amount given the force needed to shift them as you tried.

Hopefully no repeat.

  It was the fact that both aileron arms had slipped the same amount that fooled me into thinking it was a radio issue, a real fluke.

  Found that servos are Ripmax items, will look through my collection of arms.

[Frank Day]

2 hours ago, Martin Harris - Moderator said:

 

 

 

Wasn’t Frank’s post intended as an ironic comment on those who quickly jump onto threads to condemn particular systems because of problems that may have been due to external influences?

100%, Whenever there is a supposed "Radio" incident the questions frequently start with was it Spektrum. Apparently Spektrum equipped models are falling from the sky like rain.  Once the TX Rx issue was raised it had to be done.  Personally I've not seen any models falling from the sky due to a Tx issue. Brown outs, todays odd double servo issue, is very strange. I might swap out that Rx as well in case it did something odd.

[Chris Walby]

I would not change too much or if it does it again you will not know the root root cause.

IMO put the root cause down to dumb thumbs, replace the elevator servos and go fly. I would not trust servos that have been loaded to a point that the arms have rotated on the servo splines (not for elevators) Use the servos for something else (steering, rudder or flaps.. or bin them)

If it does it again the re-open the investigation.

 

 Good job with the investigation though.

 

Spektrum user over 2,500 flights and one OEM incident and the RX was +15 years old, dumb thumbs...lost count

Edited September 18 by Chris Walby

[Andy Stephenson]

As a final thought, were you using a relatively old 3rd party receiver and an LBT transmitter, there is a known incompatibility between this combination that may have caused the flight problems.

[kc]

It's good to find the reason for the problem!    It didn't waste forum members time as we all went through all possible problems and ended up finding the least expected thing was the culprit!    Good example of crash investigation and another thing to check in future.

[J D 8 - Moderator]

 To answer the last 4 posts.

 Frank, Got it now the irone, the issue was servo arm slip due to impact in the end, previous owner fitted the wrong ones. Initial loss of control was me.

Chris, It was aileron Midi servos that have the issue.

Andy, RX and TX Futaba T8j.

kc, Whole thing had me a puzzle but sorted in the end.

[Frank Day]

I tip stalled something a while ago, on collection it had an aileron stuck on full up with the servo damaged, not the side expected so must have been the impact.

[David Davis]

A couple of years ago I was bringing my WOT 4 XL into land when it suddenly veered sharply to the left and smacked into the ground. I had no control whatsoever.  It transpired that I had replaced the rudder servo with one of another make but I'd used the original output arm. The splines were different so the arm slipped on the servo. As I was low and slow at the time no serious damage was done.

[Brian Cooper]

I am late to this party but I have seen "altered" control surfaces after clubmates' models have crashed. 

 

If they had threaded 2mm pushrods with metal clevices, the different centring was due to the threads being stripped (jumped) by the inertia of the flying surface in the crash. . . especially if there were no lock nuts being used on the clevices. 

 

[john stones 1 - Moderator]

To be fair to myself, I did diagnose the answer early in the thread. 🤩

[PatMc]

On 15/09/2024 at 17:30, john stones 1 - Moderator said:

Nose down impact tends towards somethings moved, can clevices be moved under pressure, are the splines on the servo horns o.k, are horns still at 90 degrees ?

Smart Arse !! 🤗🤣

[J D 8 - Moderator]

 Cowling cracks fixed and Ripmax output arms found and firmly on servos.

Tonight decided to open up the radio bay for a check and found that both antenna were in the same orientation with the bare bits almost touching each other, the forward/downward one having come free from its fixing and naturally wants to spring back along side its partner.

   Did mention in first post that model had "flicked out" into a spiral dive rather than dropped a wing. Could this have been the cause?

   I know it is not good for antenna to be positioned so.

[J D 8 - Moderator]

        Bump on above post. Having found  the antenna as can be seen in pic above I decided on an experiment to find possible effect.

         Nothing very complicate just a basic setup of rx on a board with some servos.

        Antenna of RX in position similar to ones in model and TX in low power mode nearby no issue, all operating as normal. light solid green

        TX moved just 6 yards away and RX light now flashes green on some orientations of TX and servos sometimes do uncommanded jerking movements.

   With RX antenna held close but not touching each other signal is lost and RX light red and failsafe activated.

   Antenna in correct positions as per radio instructions and all operates as normal with TX still in low power 30 yards away.