Mini Talon crash investigation

Hi,
I crashed my beloved mini talon a few days ago.
I recently did an update to 4.0.9 and set the f.port
The flight was going without any problems when suddenly I lost control.
I don’t see anything in the logs, except a sudden noise on the RC inputs.
I need help with the investigation.
Was it a setup error? Bug in 4.0.9 or cosmic rays?

I have added the video and LOG of the crash.

Mini Talon Chrash Log

Video

Hi

your RSSI went to 0 before go down, seems like your radio get disconnected, the same way your camera did, you have lost your video just before start to fall. Did you have your failsafe configured? if your radio fails, the FC should set a RTL or something to recover the plane.

I dont see a short on the power, but in the red square you can see a small rise of voltage, this could mean some electronics have disconected, as your RC reciever and your video.

I think your RC and video went out in the air, and you didnt have your failsafe configured.

Hope this can help

That’s what I thought at first, too.

But see that the video connection is active until the end, and the image from the camera disappears because the channel that controls the video switch changes (in the plane there are two cameras installed, the switch is for three cameras, it switched to an empty - third - place). Failsafe was configured. In case of connection loss it switches to circle and then to RTL and not to manual. Failsafe was checked before the flight and after the fall.

What puzzles me is the “Decoding DSM” message right after the RSSI disappears. Is this related to the Spektrum radio?

I believe your failsafe was set up correctly. I think the problem was with the receiver.

The RC3, throttle values drop to min when everything else goes crazy. The FC doesn’t question the commands, it just does it what’s it’s told. Because the throttle value only drops for a moment to 918 (below the THR_FS_VALUE of 950) the throttle failsafe never get’s the chance to engage. Other wise the plane just does what the RC signal tells it to, and unfortunately that includes manual mode with full elevator and enough aileron for a good steep turn. Uncontrolled, well you know the outcome.

DSM typically refers to spektrum receivers. But you mentioned F-Port. What kind of receiver were you using?

I use R9 Slim+ with FLEX and F.PORT

The reason I’m talking about DSM is that on the recording right after the failure you can see the message DECODING DSM (0:07 in video)

Is it because FC suddenly thought that SPECTRUM receiver is connected?

image

I crashed my beloved mini talon a few days ago.

Sorry for your loss.

I recently did an update to 4.0.9 and set the f.port
The flight was going without any problems when suddenly I lost control.
I don¢t see anything in the logs, except a sudden noise on the RC inputs.
I need help with the investigation.
Was it a setup error? Bug in 4.0.9 or cosmic rays?

It looks like we decided that we weren’t receiving f.port input and
started decoding DSM - that didn’t work out for us.

Could you supply a log from immedaitely before you updated to 4.0.9,
please?

Hi Peterbarker

Last time I flew 4.1.0 DEV with R9 on SBUS

Log

It looks like we decided that we weren’t receiving f.port input and
started decoding DSM - that didn’t work out for us.

Looks like a bug. It is a serious issue if FC changes the protocol of the receiver during the flight. The worst thing is that this kind of errors are not caught by flailsafe.

What to do in this situation? I don’t know if I can trust Adruplane with F.Port.

It would be good if someone would look in the code what could go wrong.