MIL-STD-1557A (NOTICE 3), MILITARY STANDARD: DESIGNATION OF AIRCRAFT PROPULSION RECIPROCATING ENGINES (16 JUL 1993) [S/S BY MIL-STD-1812]., MIL-STD-1557A, dated 25 October 1983, is hereby csncelled and superseded by MIL-STD-1812, Type Designation, Assignment and Method for Obtaining.