Prioritize airspeed over altitude

I am using a Matek H743 wing and the Plane 4.0.6 Stable firmware.
The Plane is a towplane.
Therefore I need a way to fly a waypointmission in auto mode which achives 100% thrust all the time and a constant speed. (The climbrate is therefore is variable depending on the glider behind, thermals etc.)

Currently I have not setup a aspd sensor. I will use one in the future, but I would prefer to make it work based on gspd and windestimation as I want to use a redundant system, which will omit the (analog) aspd if it gets unplausible (eg. pitot tube gets dirt on it infliegt etc.)

So question 1: Is there a way to configure Ardupliot 4.0.6 to fly with the pich controlling the speed (TECS_SPDWEIGHT 2 and TECS_SYNAIRSPEED = 1 with no aspd sensor installed alone does not seem to work)
I have already found this topic which should fix my problem (basically I need glider logic -only maintain speed, forget everything else for vnav-) but i can not seem to get it working. Is the described principle implemented in 4.0.6?

Question 2: As soon as I have the aspd sensor installed, is there a way to configure ardupilot to use gspd or gspd with windestimate instead of aspd, if aspd reads unreliably?


Hey Simon, sorry i’ll be able to give this question more time next week but here’s what i know off the top of my head:

to my memory I think you had to be on the 4.1.0 beta firmwmare for this to work. That’s what I ended up doing on mine. otherwise the synairspeed and tecs_spdweight options wont work as intended for soaring. @Samuel_Tabor can give a 100% answer but 4.0.5 didn’t have this fix implemented when I was trying it and from the looks of your symptoms 4.0.6 doesn’t either.

Thank you. Is there a way to download the 4.1 beta as precompiled file for the matek h7 wing?