Thanks to Bill Manhein’s usual spectacular results on my cruddy source documents, we have now published (on BAC) the specifications for NAS302-310, and NAS312-320, control cables. Links: NAS 302-310, NAS 312-320This means that, in the case of airframe (not engine) control cables which have an NAS-prefixed part number, you can simply have McFarlane or Aircraft Spruce (or whomever) fabricate legal replacement cables. If they have the NAS code number as the part number, they are ‘standard hardware’. You can use these documents to understand what they are, confirm the part description, and order replacements as standard hardware.
In the case of cables having a 169- (19/23/24/24R), 105- (Duchess), or 108- (Skipper) part number prefix, it will require more work. You will have to get the old cable out, examine it for length, termination type, etc., and convert it to an NAS cable spec so that you can order it. You can then install it as an Owner Produced Part. See the other documentation on OPP elsewhere on BAC.
Some of these standards are a real bear to track down; and the source data publicly available is often of very poor quality. Thanks to Bill Manhein, with his research and image manipulation skills, we have been successful in yet another instance. This will prove to be a large benefit to BAC aircraft owners, as we get ever further into the maintenance of aging aircraft.