MIA93IA168

Flight experienced loss of the number one engine core cowling shortly after liftoff. Metallurgical examination of the separated cowling indicated the inboard forward cowling hinge support structure had failed due to fatigue. This allowed the cowling to open and then separate from the engine. The hinge remained in place on the aircraft after the cowling separated. The manufacturer of the cowling, which is part of an engine hush kit, requires the hinge support structure be inspected for cracks each 300 flight hours.

On August 2, 1993, at 1841 eastern daylight time, a Boeing 707-341, N107BV, operated by Fast Air Carrier, Ltd., as Aero Peru flight 014, 14 CFR Part 129, non-scheduled international cargo service from Miami, Florida, to Lima, Peru, suffered loss of the no.1 engine core cowling during takeoff from Miami International Airport. Visual meteorological conditions prevailed at the time and an instrument flight rules flight plan was filed. The aircraft received minor damage and the three flight crewmembers were not injured. The flight was originating at the time of the incident.

The captain wrote in an irregularity report to the company that the no. 1 engine cowling separated on takeoff. They dumped 67,500 pounds of fuel and returned to Miami International Airport for landing.

Post incident examination of the aircraft by the NTSB indicated the no. 1 engine core cowling had separated and was found on the runway. The inboard and outboard portions of the cowling were held together by the latching system. All latches were closed. The inboard forward core cowling hinge had separated from the cowling and was still mounted on the aircraft.

Metallurgical examination of the separated core cowling components was performed by Frank P. Zakar, Materials Engineering, NTSB, Washington, D.C. The support structure for the inboard forward cowling hinge had separated due to fatigue cracking. (See attached Metallurgist's Factual Report.)

The cowling was installed on the aircraft during installation of an engine hush kit. The manufacturer of the cowling system requires that the cowling hinge support structure be inspected for cracks each 300 flight hours. (See attached maintenance manual pages.)

At the time of the incident the aircraft was being operated by Fast Air Carrier, Ltd. as a nonscheduled international cargo flight for Aero Peru. The flight was using an Aero Peru flight number. According to Mr. George L. Wellington, Chief, Foreign Air Carrier Licensing Division, U.S. Department of Transportation, Fast Air Carrier, Ltd. did not hold appropriate DOT authority to operate the flight on behalf of Aero Peru.

The captain held a U.S. airline transport pilot certificate, issued on the basis of a foreign pilot certificate, valid for U.S. registered civil aircraft B-707 leased to MAS Air Cargo. The captain did not have a valid certificate to operate B-707 aircraft for Fast Air Cargo, Ltd. The captain was not listed on U.S. FAA records as an employee pilot for Fast Air Cargo Ltd. The first officer held a U.S. FAA certificate valid for Fast Air Cargo, Ltd. B-707 operations. The flight engineer did not hold a U.S. FAA certificate valid for Fast Air Cargo Ltd. B-707 operations.

The aircraft operator did not file an NTSB incident report as requested by the NTSB and as required by NTSB regulation.