Crash analysis needed. No nav_pitch input

Today I am flying a mapping mission. Plane take off and circle in home location in RTL mode while climb for altitude. ( I set the RTL altitude @ 350 M ) when it reach about 200 meter I put it to auto. The waypoint altitude is 170 M. It was descending and heading to waypoint one. But when it reach about 170 M it dive and loss altitude rapidly. I switch to RTL but it can not recover. I try manual in the last moment but unfortunately it was too low.
Upon replay the tlog, I notice the nav_pitch line seldom move. I think it should have some movement in auto mode. I do not know if this is a software problem or the hardware problem. I'm attach the tlog here. Please have a look if you have time and see what should I check.   
Start flying at about 70%, Please fast forward. 
Thanks for your help

2013-09-29 11-56-16.tlog

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  • Keeyen

    Did you ever find out why your CMD_INDEX was showing 0. I am currently having the same problem. Any help would be greatly appreciated.

  • Hi keeyen. how are you?

    So sad your crash, sorry.

    I noticed that CMD_INDEX was set as 0, and should be from 1 to 255, I think.

    Best regards,

  • 100KM

    I notice when the plane start to lose altitude and the nose was down, APM only increase throttle, no positive elevator output throughout the incident. Is this how APM correct for altitude loss with the old controller? I'm using 2.73

This reply was deleted.


Shivchand Jaysaval liked Shivchand Jaysaval's profile
Aug 25