RTL mode does NOT bring plane back.

I have a proven X8.  By proven I mean I've gotten 50 minutes of controlled flight out of it in multiple modes on multiple occasions.  Something has changed and I don't know what it is.

Today I almost lost it.  I had it in stabilize mode at 350ft.  I switched to RTL via my transmitter.  At that point it does a slight dive instead of maintaining its altitude at 350ft.  It went down to 180ft before I took control again.  It also DID NOT COME BACK TO HOME LOCATION.  I do not know where it wanted to go but it got about .75 miles from me and my ground crew had to help me bring it back.  I really need to solve this.  I have included my logs.

Flight starts at 40%, it is a catapult launch.  Flight ends with a tree top landing around 90%.  I try multiple times to RTL seeing if I can get the behavior I was expecting.  At around 80% the RTL command causes it to bolt (60+mph) away from the home location.

Target airspeed is never achieved, which should have been about 30mph, instead it liked 50 or more.

I had no flight mission loaded, I double checked by reading the APM via telemetry, nothing was there on purpose. 

I have a 1000mw 900mhz radio for telemetry (from rfdesigns) that is compatible with APM.  Other than that, everything is stock from 3DR.

v2.76 loaded.  APM 2.6.

I'll give all information if requested, please advise.

2014-01-20 16-24-25.rlog

2014-01-20 16-24-25.tlog

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  • Solved the pitch while in stabilize mode.  I had the wrong flight mode saved.  As in it did not save any of them for some reason.  Also I had two controls reversed, so it actually did just what it was supposed to do.  Those issues were on my Slow Stick, not the X8, the X8 problem is still present, but I'm thinking that variable might of had something to do with it.  Dunno.

  • Well, now when it hits stabilize mode (never made it to RTL) the plane pitched up drastically, rolled right, tried to spiral down.  Never seen this before, ground checks were perfect for stabilize mode.  I barely saved it, another 50 feet and I would be buying a new plane and needing fresh underwear.

  • Just by chance I see in the list of full parameters that the ALT_HOLD_RTL is set to 10,000 CENTIMETERS.  WTF!  I did not set this.  4000ft.  Going to test this with my Slow Stick.  I set it to -1 which will be for the plane to hold the altitude it was at when it entered RTL.  THIS IS SERIOUS.  10,000 centimeters???

  • looking at the logs, the home location is indeed correct, but if I look at distance to home it is at a different previous location.  I dont know if that is correct as I'm at my house and that is where I last fired up the APM.  It appears to remember that even though I am running a log.  So, its showing the right home location, but on my desktop it is treating my house as the home location.  Confusing.

  • Anyone?

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