Crash after numerous flights without problems

[DUKE40]

Hi,

my AQ has already 117 flights without any issue or big crash, and today suddenly it flipped in about 20 meters above ground, most probably due to wind gust.
Nothing broken apart from some nylon screws, among them the one holding the AQ to the frame.
When powering the AQ, nothing happens, no LED, everything remains dark.
Attached the log of the last flight with the crash.
I have no idea what is wrong with the AQ, and even more no idea how to get this corrected.
It is very sad, as this was the final test and setup flight for the gimbal before going into holiday where I had planned to take a lot of videos.
Looking at the AQ, I cannot see anything which looks broken or any loose soldering.
Here the log of the HoTT telemetry:
Motors init
Control init
Control task started
Gimbal init
Gimbal PITCH stabilization port initialized.
Radio task started
GPS task task started
Gimbal ROLL stabilization port initialized.
Gimbal TILT control port initialized.
HoTT Telemetry init
AQ S/N: 36373532-33314719-00220025
Mavlink SYS ID: 11
SYS Clock: 168 MHz
8274/8274 heap used/high water
30536 of 38912 CCM heap used
Run task started
HoTT Telemetry task started
AQ FW ver: 7.0 - EXPR rev38912 b1673, HW ver: 6 rev1
Disarmed
Initialization complete, READY.
Armed
GPS: trying new baud rate
RTC set: 2014-05-15 12:37:33 UTC
Altitude Hold engaged
Home position set
Position Hold engaged
Home position set

So there is nothing looking strange.
I wanted to attached the log, but it is too big even zipped it is more than 7MB which is above the limit here.
I would be very thankfull if I could get any help to get it flying again.

[joebar.rc]

Everything dark?, are the recoms outputting 5V?, the recom near the ublox GPS receiver is the one that powers the main AQ circuit.

Menno

[DUKE40]

Yes everything dark. How do I check the recoms?

[joebar.rc]

With a multimeter . The recoms have 3 pins, depending on which AQ side your testing;
the pins are main input, gnd, 5v so measuring over gnd and 5v pin would need to output... the 5v

[DUKE40]

The recom near the Ublox does not show any voltage between eny outside pin (Vin or Vout) and the middle pin (GND), thus it seems it does not even get any voltage at the input, no wonder nothing at the output.
What should I check now?

[DUKE40]

I hoped to get some more feedback to y problem and waht could be done to get my AQ airborne again.
But obviously no one has an idea what could be wrong and what could be done to get it back to life.
Thus it makes no sens to further investigate what might have caused the crash, as it will remain grounded perhaps for ever.
Very sad. As I do not have the possibility financially to replace such an expensive part. My AQ will remain grounded for a long time.
I will go back to my old NanoWii quad which is still flying.

[kinderkram]

Sorry for the crash, Duke.

Please upload your logfile anywhere or send it via email. Did you look at it? You might find a hint whether the electrical failure was the cause or the result of the crash.

And then you need to find out which part fails - but I´m no big help as I would need help myself in such a case...

Sorry,

Norbert

[JussiH]

As Norbert says, we need to see the log file. Put it in dropbox or similar and link it here - it could contain vital clues to what failed. Lots of events could lead to the described behavior, the most likely beeing ESC failure or power distribution short circuit.

But without the log we´d be guessing.

The fact that the recom is dead makes it likely that the board was subjected to a short circuit or reverse voltage on Vin. Check all ESC´s and the whole power distribution for shorts. A wire rubbing on a CF part edge can cause a short in no time.

Pls try something:

Check if there is continuity from Vin pin to Recom input pins?

Connect the board to a limited power supply - 500 mA/12v max. Check if the main MCU and the small 8-pin IC next to the serial pins on the top side is heating up?

When was the board bought and where? (need to know which batch it came from)

In any case, I want to help you get back in the air, so if you send the board back here I will repair it or replace it with another from the repair pool.

[DUKE40]

Hi Norbert,

the log is too big, to be uploaded in the forum, but I could send it to you via eMail.
Zipped it is still 8Mb.
But attached the last part of the log, which in this case most probably the interesting part.

005-AQL.LOG

(3.12 MiB) Downloaded 716 times

I have already had a look at it, but could not recognize for sure if the failure is a result of the crash, or the crash a result of the failure. I have the feeling that the failure occured after the crash.
Would be of great help if somebody else could have a look at the log file.

[DUKE40]