Q450 4.0.3 Crash


I finally got my quad tuned nicely, so I added some landing skids to it and tried to run autotune again.
All was going well until it was almost finished, at which point it slid sideways out of the sky and crashed.

I noticed that the battery was not secured properly when I recovered the quad after the crash. For this reason, my working theory is that the battery came loose during tuning, putting the quad off-balance.

When I do look at the logs I see this:

This kind of indicates to me that the GPS had a catastrophic failure, and decided the altitude was 250m under the earth’s surface. Am I reading this correctly?

Unfortunately my log analysis skills are not good enough to confirm either theory.

The specs are as follows:
Frame: Q450
Motors: Emax 2216 (810Kv)
Battery: 5000MaH 4S
Controller: Pixhawk (clone)
Firmware: Arducopter 4.0.3

Here is the auto-analysis of the last flight:

Log File C:\Users\shane\AppData\Local\Temp\tmp6074.tmp.log
Size (kb) 51404.7509765625
No of lines 594293
Duration 0:18:22
Vehicletype ArduCopter
Firmware Version V4.0.3
Firmware Hash ffd08628
Hardware Type
Free Mem 0
Skipped Lines 0
Test: Autotune = UNKNOWN - [?] Autotune 20084-578976

Test: Brownout = GOOD -
Test: Compass = FAIL - Large change in mag_field (47.00%)
Max mag field length (708.79) > recommended (550.00)

Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = FAIL - ERRs found: FLT_MODE CRASH GPS_GLITCH
Test: GPS = UNKNOWN - join() takes exactly one argument (2 given)
Test: IMU Mismatch = FAIL - Check vibration or accelerometer calibration. (Mismatch: 2.00, WARN: 0.75, FAIL: 1.50)
Test: Motor Balance = WARN - Motor channel averages = [1404, 1430, 1469, 1482]
Average motor output = 1446
Difference between min and max motor averages = 78
Test: NaNs = FAIL - Found NaN in CTUN.DSAlt

Test: OpticalFlow = FAIL - FAIL: no optical flow data

Test: Parameters = FAIL - ‘MAG_ENABLE’ not found
Test: PM = GOOD -
Test: Pitch/Roll = GOOD -
Test: Thrust = GOOD -
Test: VCC = UNKNOWN - No CURR log data

The logs from the last flight can be found here:

Can someone please take a look at the log and let me know what you think the problem is?

Looks like motor/prop/ESC #1 failed

You can see here where M1 goes to max shortly before losing altitude.

To highlight it here we have desired v actual and you can see M1 goes max then DvA departs and finally altitude goes down.

That’s great.
Thanks very much, Mike.