This addendum provides additional requirements over those published in IPC/WHMA-A-620A to ensure the performance of cable and wire harness assemblies that must survive the vibration and thermal cyclic environments getting to and operating in space. Where content criteria are not supplemented@ the Class 3 requirements of IPC/WHMA-A-620A apply Purpose When required by procurement documentation/ drawings@ this Addendum supplements or replaces specifically identified requirements of IPC/ WHMA-A-620A.