AI Aircraft sway and slow on approach.

[ColR1948]

I recently downloaded a Cessna 185 Skywagon, I used it for an AI, it performed good with a VFR TNG flight plan.

Then I tried it with an IFR plan, it flew OK till it got to the approach, then it started to sway left and right and was almost at a stand still, moving forward very slow, it did touch down eventually but obviously not right.

 

I had this happen on another aircraft a while ago and forgot what I did to rectify it, the only thing I could think of was to edit the cfg, I found a Mooney Bravo that was almost the same weight so I copied the dynamics and used those, tried the Cessna again and it flew great, approach was good so no problem.

I also copied the Mooney air file too and used that.

 

Going back a step or two I did find another Cessna 185 but that flew a bit too slow and again on approach it didn't sway but almost hovered moving very slow forward.

 

So instead of having to search for a similar ac to edit the cfg I was wondering what makes this action happen, is there a simple tweak to rectify it?

[pschlute]

Was the Cessna designed as an AI aircraft ?

[tiger1962]

Hi ColR, check that the 185's aircraft.cfg contains the following sections:

 

[autopilot]

[attitude_indicators]

[direction_indicators]

[turn_indicators]

 

If it doesn't, copy and paste them from the default 172's aircraft.cfg.

[ColR1948]

@pschlute, No mate it is a flyable, I couldn't find an ai version, I've used flyables before though, sometimes needing a tweak other times none.

 

@Tiger1962, Yes those sections are/were in the cfg.

[johnhinson]

If it helps, C185s for AI can be found in this set:

https://www.fspilotshop.com/htai-models-cessna-single-engine-props-p-613.html

 

John

[old_wombat]

One reason an aircraft will suddenly sway is if you are getting close to stall speed. As you were slowing down, had you noticed you were suddenly having to put on a fair bit of nose-up pitch?

[pschlute]

One reason an aircraft will suddenly sway is if you are getting close to stall speed. As you were slowing down, had you noticed you were suddenly having to put on a fair bit of nose-up pitch?

 

He is using the aircraft as AI, not flying it.

[ColR1948]

@johnhinson, Hi John, I did see that but it was payware about £13, I know it won't break the bank but I looked for a free one.

I did find another here on this site, I tried it and it flew OK but it had one of my bug bears, those horrible big balloon lights, I can't stand them.

I keep looking to see if there is a way to HEX edit them out but no luck yet.

[tiger1962]

Steve has made a good point Col, it looks like the C185's flaps are causing too much drag. Try reducing the drag_scalar in the [flaps] section of the aircraft.cfg.

[ColR1948]

I have been busy today but I just compared the Flaps section in the cfg with the one I have working that I used from the Mooney to the one that came with the Cessna.

 

Yes the drag_scaler=2 (Cessna) drag_scaler=1(Mooney) plus a few other differences, thanks I will try it later.

[ColR1948]

I changed the flaps setting as above and it did stop the swaying from left to right but the approach was still very slow, so for now I'll stick with the Mooney cfg.