Plane: nav_controller_output fix airspeed error units

[lekston]

Just a follow up for the issue #7932.

[WickedShell]

@magicrub this has been discussed on the dev call before. The conclusion as of ~a month ago (I'd have to find the dev call notes to tell you when we discussed this) was that we should update/correct the units on it. (I was surprised as this didn't match the decision 2 years ago, but that's fine). I don't think we need to discuss it on the dev call at this point, just need to make sure GCS authors are aware we are correcting it.

[tridge]

we've decided to hold this off until we add a mavlink2 extension for target_speed, and type of target_speed (airspeed vs groundspeed). That will fix the issue and allow us to change units, while also fixing the jitter in the target_airspeed calculation in the GCS

[arikrupnik]

It appears there are two places in this code that report cm/s instead of m/s. The one under discussion here, and a couple of lines above it in tailsitter code:

ardupilot/ArduPlane/GCS_Mavlink.cpp

Line 173 in 1264567

plane.airspeed_error * 100,

[peterbarker]

#18816

[hendjoshsr71]

@peterbarker Would you mind fixing the title on this one to be easier to find via search? I did do a search and nothing came up since GITHub search isnt so awesome.

[peterbarker]

@hendjoshsr71 to what? :-)

[hendjoshsr71]

@hendjoshsr71 to what? :-)

Maybe just "Plane: nav_controller_output fix airspeed error" but I'm biased :)