1967 — March 5, Lake Central Air 527 right-motor failure/crash near Marseilles, OH– 38

— 38 Aviation Safety Network. Accident Description. Lake Central Air Flight 527, 5 Mar 1967.
— 38 Kimura. World Commercial Aircraft Accidents 3rd Ed., 1946-1993, V.1. 4-11-1994, p.3-10.
— 38 NTSB. AAR. Lake Central Airlines…Near Marseilles, Ohio, March 5, 1967. 1968.

Narrative Information

NTSB: “About 2007 e.s.t., on March 5, 1967, Allison Prop-Jet Convair 340, N73130, being operated as Lake Central Airlines, Inc., Flight 527, crashed near Marseilles, Ohio. The 38 persons aboard the aircraft received fatal injuries. The aircraft was destroyed.

“Investigation revealed that all four blades of the right propeller separated in flight and the No. 2 blade penetrated the aircraft fuselage in line with the propeller plane. The penetrations destroyed the structural integrity of the fuselage to an extent that, together with the loads caused by a right yaw which accompanied the propeller separation, the fuselage failed along the line of penetrations and the aircraft crashed.

“Examination of the internal mechanism of the right propeller revealed that the helical spines of the torque piston of the No. 3 blade pitch change unity were worn away and the torque cylinder was completely failed. The wear of the spines was due to an omission of nitriding for surface hardness during manufacture and the cylinder failure was caused by fatigue.” (NTSB. AAR, p.1)

“When the torque cylinder failed, propeller oil pressure maintaining the pitch position of the right propeller blades was lost. The blades moved toward low pitch at a rate too rapid for the propeller pitch lock to operate effectively. At a low blade angle the propeller oversped, causing the blades to separate in overstress.

“The Safety Board determines that the probable cause of this accident was a failure of the right propeller due to omission of the torque piston nitriding process during manufacture, and the failure of manufacturing quality control to detect the omission.” (NTSB. AAR, 1968, p.2.)

“…Lake Central Airlines Flight 527 was a scheduled passenger operation between Chicago, Illinois and Detroit, Michigan, with intermediate stops at Lafayette, Indiana, and Cincinnati, Columbus, and Toledo, Ohio….Flight 527 left Chicago at 1704 and progressed with no reported difficulty to Columbus where it arrived at 1935. It departed Columbus for Toledo 17 minutes later…About 2005 the flight was cleared from its assigned cruising altitude of 10,000 feet to descend to 6,000 feet, and to report leaving 8,000 and 7,000 feet. Crew acknowledgement of the clearance and a report that the flight was leaving 10,000 feet was the last transmission from the aircraft. At 2007 the radar target of the aircraft…disappeared from the controller’s radar scope.

“At times variously estimated as between 2005 and 2010, persons in the vicinity of Marseilles, Ohio, heard sounds from an aircraft. Some of the descriptions of sounds were: ‘like an engine revving up,’ ‘like a car stuck on ice’ and ‘like a sports car on a drag strip.’ It was reported that a few seconds later there was an explosion like sound and after another short interval the sound of a heavy impact. It was soon determined that an aircraft had crashed and by about 2100 it was established that the aircraft was Lake Central Flight 527 and that all 38 persons, 3 crew and 35 passengers, aboard had been killed. The crash location was 2 miles southwest of Marseilles… (NTSB. AAR, 1968, p.3-4.)

Sources

Aviation Safety Network. Accident Description. Lake Central Air Flight 527, 5 Mar 1967. Accessed 3-1-2009 at: http://aviation-safety.net/database/record.php?id=19670305-0

Kimura, Chris Y. World Commercial Aircraft Accidents 3rd Edition, 1946-1993, Volume 1: Jet and Turboprop Aircrafts. Livermore, CA: Lawrence Livermore National Laboratory, Risk Assessment and Nuclear Engineering Group. 4-11-1994.

National Transportation Safety Board. Aircraft Accident Report. Lake Central Airlines, Inc., Allison Prop-Jet Convair 340, N73130, Near Marseilles, Ohio, March 5, 1967. Washington, DC: NTSB (File No. 1-0001), February 26, 1968, 36 pages. Accessed at: http://www.airdisaster.com/reports/ntsb/AAR68-AC.pdf