A Boeing 737-230, operating as Nationwide flight 723, departed from Cape Town International Airport (CPT) on schedule at 15:50. During a takeoff from runway 01, the right-hand engine separated from the wing. During rotation the crew noticed a sudden spool down indication on all right-hand engine gauges, followed by drastic attitude changes. The aircraft was banking towards the left and right side, then started to sink and thereafter yawed to the right. The right-hand engine thrust lever retarded uncommanded and the reverse thrust warning light also illuminated and remained on. The crew managed to recover the aircraft from the uncommanded roll to both left and right and was able to establish a normal flight attitude. An emergency was then declared and the aircraft continued to climb and remained at an altitude of 3000 feet above mean sea level (AMSL), as it was vectored along the circuit by the ATC. The flight deck crew carried out one orbit with the aircraft prior to them receiving clearance to land on runway 01. A safe landing on runway 01 followed. PROBABLE CAUSE: “The right-hand engine separated from the aircraft due to the failure of the aft cone bolt as a result of a pre-existing fatigue crack which was most likely caused by incorrect installation of the cone bolt.”