Mad Cow Nike Apache two stage rocket fails to light sustainer. Booster Motor was Aetotech J500 and with H195 DMS in sustainer. After separation, the booster coasted to 1700' before deploying a main with chute release. The sustainer coasted up to 1,926'. All recovery events occurred safely and correctly. Missileworks RRC3 altimeters in both booster and sustainer with aux channel to fire separation charge and sustainer ignitors if vertical velocity conditions are met. Cause of failure was separated ignitor wiring following boost or separation.