Unable to stabilize vtol/tail-sitter, need advice

ArduPlane VTOL Plane
1

Hi All,
our first vtol but after multiple unsuccessful attempts … we a little bit lost. All on youtube seems just setting few parameters and able to at least hover without issues … but either we are not lucky enough or missing some very basic things … but not able to spot the issues yet …
all our attempts seems stable … it is able to take off then crashing during attempts to stabilize…

can somene take a look on the params/logs/video and help with some ideas what’s wrong with this setup … it seems everybody able to hover with piece of wood … but its surprisingly hard for unknown reason …

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video/logs/params - vtol - Google Drive

Appreciate your time and advice.

2

try q_tailsit_gcsmsk =4

3

What is your tailsitter configuration? Is this non-vectored dual motor tailsitter? I guess your motors are connected to ch4 and ch5, nothing to ch3…
If this is so, I think your elevon is too small, prop diameter is also too small. Non vectored dual motor tailsitter needs 30-50% chord size of elevon, and large diameter prop to cover elevon with stream. Otherwise better to look into vectored tailsitter.
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For non-vectored dual motor tailsitter, my thread records almost a year of learning and may help.