1960 — July 27, Chicago Helicopter Airways blade failure and crash, Forest Park, IL–all 13

–13 CAB. AAR. Chicago Helicopter Air… Sikorsky S-58c Forest Park, Illinois, July 27, 1960.
–13 Gero. Aviation Disasters: The World’s Major Civil Airliner Crashes Since 1950. 1996, p. 36.

Narrative Information

Civil Aeronautics Board: “On July 27, 1960, at 2238 c.d.t., a Sikorsky S-58C helicopter, N 879, operated by Chicago Helicopter Airways, Inc., as Flight 698, crashed and burned in Forest Home Cemetery, Forest Park, Illinois. The aircraft was demolished. The crew members [2] and 11 passengers were killed.

“N 879 arrived at Chicago Midway Airport from Chicago O’Hare Airport at 2215 c. d. t. It was serviced and scheduled to leave Midway at 2230 c. d. t., as Flight 698 for O’Hare Airport, 17 miles away. The flight departed on schedule in VFR weather conditions. All radio transmissions were routine.

“When the flight had cruised to about the midpoint of its trip, a part of one of the main rotor blades broke away. The helicopter began to descend with its landing lights on. Sounds similar to the rapid cracking of a bullwhip were heard by witnesses. Moments later, the tail cone and tail rotor separated from the aircraft, and the angle of descent increased. The helicopter spun around its vertical axis – crashed nose-down on its left side – and burst into flames.

“The Board determines N 879 became uncontrollable and crashed as a result of a structural disintegration in flight, initiated by a fatigue fracture of a main rotor blade.

“On August 3, 1960, the Federal Aviation Agency issued Airworthiness Directive 60-17-3, Amendment 191, Part 507 Federal Register, August 19, 1960, which elaborates the inspection requirements of main rotor blades, and limits their service time [from 2,450] to 1,000 hours….

“Flight 698 was the seventh for N 879 on the 27th and there were no pilot squawks entered on the flight log. The operations consisted of trips back and forth between Midway and O’Hare Airports by a route 17 nautical miles in length and over open areas suitable for autorotation landing, should an emergency require it.” (CAB. AAR. Chicago Helicopter Air… Sikorsky S-58c Forest Park, Illinois, July 27, 1960.)

Gero:
“Date: 27 July 1960 (22:38)
“Location: Forest Park, Illinois, US
“Operator: Chicago Helicopter Airways (US)
“Aircraft type: Sikorsky S-58C (N879)

“The first fatal crash of a commercial helicopter engaged in a regular passenger operation occurred during a commuter service between Chicago’s two air carrier airports, from Midway to O’Hare International.

“Flight 698 was cruising at its assigned height of 1,500 ft (c 500 m) when one of its four main rotor blades snapped. After it had descended to a lower altitude, its tail rotor and cone separated from vibrations generated by the imbalance of the main rotor assembly, attributed to the loss of the blade, and the aircraft then crashed in a cemetery and burst into flames, killing all 13 persons aboard (11 passengers and two pilots). The accident took place in darkness and clear weather conditions on the outskirts of Chicago, approximately half-way between the two airports.

“The failure of the main blade was initiated by a fatigue fracture, which had apparently developed in the 68 hours of flying since its last inspection.” (Gero, David. Aviation Disasters: The World’s Major Civil Airliner Crashes Since 1950 (Second Edition). 1996m p. 36.)

Sources

Civil Aeronautics Board. Aircraft Accident Report. Chicago Helicopter Airways, Sikorsky S-58c, N 879, Forest Park, Illinois, July 27, 1960. Washington, DC: CAB, 14 Aug 1961, 11 pp. Accessed 11-16-2022 at: https://rosap.ntl.bts.gov/view/dot/33644

Gero, David. Aviation Disasters: The World’s Major Civil Airliner Crashes Since 1950 (Second Edition). London: Patrick Stephens Limited, 1996.