AD 87 does refer to stainless steel fitting not copper type. It relates to the the stress corrosion that Stainless is very prone to. Very common on yacht fitting, most insurance companies won't insure yachts with stays over ten years old, some less! Fittings can look perfect on the outside and be rotten inside.
The AD is not referring to the cable, it's the fittings.
That's my take on it. Cheers, Brian
AD/GENERAL/87 Primary Flight Control 2/2015 Cable Assembly Retirement
Applicability:
This AD applies to any aircraft fitted with primary flight control cable assemblies using terminals constructed of SAE-AISI 303 Se or SAE-AISI 304 stainless steel which have total time in service of, or exceeding, 15 years unless the:
(a) aircraft is maintained to MSG-3 methodology; or
(b) instructionsforcontinuingairworthinessfortheaircraftspecifiesalifelimit for the primary flight control cable assemblies that is less than 15 years of total time in service and the instructions are complied with.
Note: Affected terminals include, but are not limited to, terminals manufactured to MS20658 (AN658), MS20667 (AN667), MS20668 (AN668), MS21259 (AN666) and MS21260 (AN669 or NAS650), which may be stamped on the terminal.