Plane crash during Auto TakeOff

[kikislater (Sylvain POULAIN)]

@VRquaeler

This is not true. I have performed a 3 digit number (more than 100) of successful “Auto Take off’s” on different ArduPlane versions from 3.9.4 up to 4.0.6 without the need of a compass.

+1 Same for me.

@mavic How do you calibrate your FC ? With Mission planner or QGroundcontrol ? I found one issue with QGC calibration, it reverse board orientation : it costs me a motor and servo …

[mavic]

I only used mission planner.

[Ojwhaaa_Ojwhaaa]

I had the exact same problem and here is my solution also:

AR Wing pro with Ardupilot and Matek f765 Auto takeoff failure

The first flight was a crash https://youtu.be/v9kJxqnlKHE I think there is a problem with auto takeoff, TKOFF_LVL_PITCH=15 but the plane went down, what am I doing wrong, please help… TKOFF_ACCEL_CNT,1 TKOFF_ALT,30 TKOFF_DIST,200 TKOFF_FLAP_PCNT,0 TKOFF_LVL_ALT,20 TKOFF_LVL_PITCH,15 TKOFF_PLIM_SEC,2 TKOFF_ROTATE_SPD,0 TKOFF_TDRAG_ELEV,0 TKOFF_TDRAG_SPD1,0 TKOFF_THR_DELAY,2 TKOFF_THR_MAX,95 TKOFF_THR_MINACC,6 TKOFF_THR_MINSPD,0 TKOFF_THR_SLEW,25 TKOFF_TIMEOUT,0

[VRquaeler (sascha)]

@Allister
Most of the time I use Auto take off as part of a mission in “auto” mode. Back in the days of AP3.9.xx versions the option of AutoTakeOff as flight mode was not available. I kept using the old way. It just works for me.
PS: I like your kind of humor. We all know this situations …

@kikislater
Thanks for confirmation. I would be amazed if I would be only one who achieved this.

@mavic
After watching the videos of the failed attempts to me it looks like you throw the plane with a lot of spin. This is too much for the flight controller to compensate. Especially at low speeds after a tame launch.
Try to push the plane more straight in to the wind.

Your settings should be good enough, You already achieved a successful flight.

A few more tips which worked for me:

• Try the first flights (take offs) with more wind. It helps at launch.
• If it does not work. Remove some equipement to make the plane lighter
• Try a lighter battery (while maintaining the right CoG)
• After some successful launches you will be more confident and get a better understanding of the weight the plane can handle
• last but not least: make a few fast steps against the wind while throwing the plane to increase the launch speed

Hope this helps.

[Allister (Allister Schreiber)]

@VRquaeler @kikislater
You guys have me questioning some of my understanding of compasses during take off. (not a bad thing, it’s how we learn) I started another thread to discuss it so I don’t derail this one too much. Thanks!

[mavic]

I finally got stable takeoffs by following these tips and analysis logs. Two more changes helped my launching are

1. overhead launch works better than side throw for my ar wing pro
2. raise the nose 5 degrees up when calibrating level. This makes the take off much better.

Thanks again @Allister and all guys.

[Alfredo_Mugo (Alfredo FW)]

hello i do not have compass.

Do the plane need to face the same heading when in takeoff mode as the same same when i plug in the battery?

cheeres