Thank you all for the replies, I will follow everything up and see what I can find out.
Basically some fixed wing colleagues of mine are doing a lot of work with the British Disabled Flying Association, and have a set of removable controls that can be fiited to an Archer to allow them to control the rudder by hand.
There is no keeping these people down and many of them want to have a bash at the helicopter, and hence the enquiry.
It is an inspiration to work with these people and I want to do what I can to help.
Many thanks all