vbar crash, case and rescue

Hi there,

I mistakenly resourced to my Vbar rescue to get out of a bad situation in flight, and I regret it. Rescue didn't work at all. It acted as if it wasn't there. Consequently, I crashed hard and expensively. That is one of those occasions you regret not having tried to solve your problem on your own.

Every flight, before take off, I bother to flip the switch to see if rescue works, and it did, but not in flight.

Also, as a consequence of the crash, I found the case of the unit broken and the unit circuit board partially exposed.

At home, I taped the case, tested the unit and all servos seem to be working right, including rescue. In the log I couldn't see any unusual entry that explained why rescue did not work in flight.

Questions:
- do you guys think this unit is reliable to fly again?
- is there a way to make sure rescue is working perfectly?
- what could have caused rescue not to work in flight?
- I taped the unit case and it looks and feels solid again. Should I replace the case for a new one?

Thanks



3 mal bearbeitet. Zuletzt am 21.02.2019 18:39 von ReadyToFly.

Hi RTF,

- hard to tell from a distance
- you can only do extensive tests on the ground, with the mechanics running, no blades, wiggle the wires etc. If there was an obvious defect, the VBar would warn (like sensor elements not initializing properly). If there was mechanical damage, broken soldering joints etc., the VBar would not work or not properly work, e.g. servos stopping/resuming if you wiggle the wires/connectors.
- please attach the log file from the VBar itself, read it from the unit with the setup software

What radio are you using, and what type of input (button/switch), and which states does the switch show when you actuate Rescue on the ground, in Setup, on the Receiver panel?

Kind regards

Eddi

Born to fly ...
forced to work.

hi,
Thanks.
Here you go the log file.
It is hard to say which one is the flight of interest because I have initialized the unit quite a few times after the crash.
The radio is a Vcontrol and the rescue switch is the buddy one.
I have just tested the unit on the bench and everything seems to work fine, rescue included. Wiggling the wires will not cause any undesired effect. Everything looks normal, however I could not see any bar changing on the pc screen when I flip the rescue switch.
On Vcontrol, flipping rescue causes something to change on the rescue section screen, though.
On the bench, independently of what happens on the pc/Vcontrol when I flip rescue, the swash plate always jumps as expected when I do it.
I still did not have the opportunity to spool the heli up. I am waiting for parts. The tests I did on the bench targeted the servos only.
Thanks again.



1 mal bearbeitet. Zuletzt am 21.02.2019 22:22 von ReadyToFly.

Hi,

from the Log, I would say the fourth-last section is the one with the crash (marker: Sensor out of Range, when the sensors detect a shock impact).
This would mean, the model hit the ground at 1:50 after power on, would that compute?

What strikes me as odd, you say you are using VBar Control. In the beginning, there are the tell tale log file entries from a properly set up VBar NEO, motor status changes. In the end, no more.

So I would change my interpretation and say that the section on pg. 4/5 is the one, which ends at 3:50 with "Rescue has been activated".
But this would mean, that at this time, the power supply was instantly lost, because the VBar would log until the end, even if e.g. the radio link was lost or whatever else could happen, and it would log "Rescue has been completed" no matter what, either if the process has actually been completed, or after a four second timeout, if the system was not/no longer able to do it, for example if a link would pop off or if the model would hit the ground in between, and come to rest not at an upright position.

With this interpretation, the fourth-last section could also show effects of handling the VBar on the ground, a quick motion can also raise the sensor out of range entry.

Can you explain in more detail how the incident evolved, what you did notice during the last couple of seconds?
Did you find anything out of the ordinary after the crash? I guess the model was at least no longer powered when you came to pick it up.
More info about the model and the components used could also help shedding light on the situation.

As being said, it looks like the last input logged was the actuation of Rescue, the command did definitely reach the VBar. After that, nothing, like lost power.

Born to fly ...
forced to work.



1 mal bearbeitet. Zuletzt am 22.02.2019 09:01 von Eddi E. aus G..

hello Eddi,

Thanks.

Quote:

So I would change my interpretation and say that the section on pg. 4/5 is the one, which ends at 3:50 with "Rescue has been activated".

yes, I think the section of the crash is this one you have just mentioned:

OK 0:00 Reset Reason: Power On
Info 0:05 Calibration Finished
OK 0:15 Good Health Message (10sec)
Info 0:22 Rescue has been activated
Info 0:23 Rescue has been completed
OK 0:33 Good Health Message (10sec)
OK 0:43 Good Health Message (10sec)
Info 0:49 Bank 2 Loaded
Info 0:50 Governor Mode Pitch
Info 0:50 Motor Switch operated to ON
Warn 1:00 High Vibration Level
OK 1:10 Good Health Message (10sec)
Warn 1:18 High Vibration Level
Info 1:28 Raised Vibration Level
Warn 1:37 High Vibration Level
Warn 1:46 High Vibration Level
Info 1:55 Raised Vibration Level
Info 2:04 Raised Vibration Level
Info 2:13 Raised Vibration Level
OK 2:23 Good Health Message (10sec)
Info 2:32 Raised Vibration Level
Info 2:41 Raised Vibration Level
Info 2:50 Raised Vibration Level
Info 2:59 Raised Vibration Level
Info 3:09 Raised Vibration Level
Info 3:18 Raised Vibration Level
Warn 3:27 High Vibration Level
Info 3:36 Raised Vibration Level
Info 3:45 Raised Vibration Level
Info 3:50 Rescue has been activated

I say that because this is the flight in which I had governor activated but not deactivated.

Quote:

With this interpretation, the fourth-last section could also show effects of handling the VBar on the ground, a quick motion can also raise the sensor out of range entry.

The subsequent sections are me on the bench testing the unit.

As far as I can remember I found the batteries disconnected on the crash site. So, yes, the unit lost power when the heli hit the ground because the batt connectors separated. It probably explains why rescued did not complete.

The heli was a Logo 600SE with ds615 servos, CC 120hv, and CC 20a BEC.

What I am sure is that I have hit rescue 1-2 seconds before the crash and absolutely nothing happened. Heli was very low, but high enough for rescue to save the situation, especially because it pitches the heli up before inverting it to the upright position (the heli was inverted at the moment of the crash).

I am currently flying with a Vcontrol, but in the past I was using a Futaba. So, some sections may suggest I have a Vcontrol and, others, that I have a different radio.

The unit seems to work perfectly on the bench. There are no bad connections as far as I can see. I put the case halves together with some tape, what I will always be doing from now on on any unit, just is case the unit case considers the possibility of breaking or separating.

I was wondering if there is some test I can do to verify if the rescue sensor is good.

Thanks again.

Hi again,

well, if the battery disconnects in a crash, you usually still have a vibration, cyclic ring or sensor out of range entry after Rescue was actuated, unless the model goes in at full speed, and the time to the forced disconnection of the battery is really brief.

I just can not imagine why the power should cease instantly at the time you actuate Rescue, unless, at that time, connectors already on edge slipped.

You basically get the same entries with a VBar Control and with a third party radio _if_ the VBar is set up properly. But if you e.g. bypass the throttle logic and connect the ESC to AUX3, using throttle curves from your radio, you would possibly get no motor switch entries unless you assign a separate channel to set the motor status accordingly.

Anyway, all you can do is thoroughly test, wiggle the wires and connectors, make sure the main board is fixed securely inside the case, and check the event log for tell tale entries. Also check the Rescue Status of course.

Kind regards

Eddi

Born to fly ...
forced to work.