I have now tried my WIP and found that I needed to change the way that I added extra variables in the /fdm/jsbsim/fcs property tree. Previously I did this in Nasal:
props.globals.getNode("/fdm/jsbsim/fcs/afcs-left-taileron-cmd-deg", 1).setDoubleValue(0);
props.globals.getNode("/fdm/jsbsim/fcs/afcs-right-taileron-cmd-deg", 1).setDoubleValue(0);
props.globals.getNode("/fdm/jsbsim/fcs/afcs-rudder-cmd-deg", 1).setDoubleValue(0);
props.globals.getNode("/fdm/jsbsim/fcs/afcs-throttle-cmd-norm", 1).setDoubleValue(0);
Now I have to do this the start of the aerodynamics section of the JSBSim Xml file
    <axis name="LIFT">
I also set the initial values (all zero in this case) when I re-initialise my autopilot after an in-air reset.
It is likely that other aircraft that use user added properties within /fdm/jsbsim/fcs/ tree will need similar changes.
Other than that all seems to work as before.
Sent: Friday, March 07, 2014 8:48 AM
Subject: Re: [Flightgear-devel] Reset & reposition
On 6 Mar 2014, at 14:38, James Turner <zakalawe@mac.com> wrote:

I’ve been testing this with the C172, and ‘quite severe’ is correct, sometimes the aircraft is pointing straight up or down.
The problem goes away when I restore the initial property state - but that’s something I’m trying to avoid since it causes other issues and makes ‘reposition’ more like ‘reset’.

I pushed a couple of fixes in this area last night. (One is more of a work-around I shall be chasing on the JSBsim side).
Please update to latest FG and let me know if the situation is improved at all!
Kind regards,

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