We have a program callled sail-ability which uses cat rigged dinghy's and a 'joystick' which steers and pulls on or releases the main sheet. Disabled sailers _usually kids sit next to an instructor and sail around the bay / harbour etc.
Also another program' for blind sailors is running at a club level and has trips from day sailiing to circumnavigating australia.
I have met a few sailors (old salts) who are now blind. They still go out (with sighted people) but their input is invaluable. They can tell if off course or sails flapping etc.
The old adage applies (- excuse me Nike) - "just do it"