1960s • On 2 February 1966,
Pakistan International Airlines Flight 17, operated by a Sikorsky S-61 helicopter registration AP-AOC, crashed on a scheduled domestic flight in
Faridpur Division,
East Pakistan after the main gearbox failed, killing 23 of the 24 passengers and crew on board. • On 10 December 1966, a
Pakistan International Airlines Sikorsky S-61 helicopter registration AP-AOA crashed on a scheduled domestic flight in
Dhaka,
East Pakistan. • On 22 May 1968,
Los Angeles Airways Flight 841 crashed near
Paramount, California, resulting in the loss of 23 lives. The accident aircraft, N303Y, serial number 61060, was a Sikorsky S-61L en route to
Los Angeles International Airport from the
Disneyland Heliport in
Anaheim, California. • On 14 August 1968,
Los Angeles Airways Flight 417 crashed in
Compton, California, while en route to the Disneyland Heliport in
Anaheim, California from
Los Angeles International Airport, resulting in the loss of 21 lives. The accident aircraft, N300Y, serial number 61031, was the prototype of the Sikorsky S-61L.
1970s • On 25 October 1973, a
Greenlandair S-61N, OY-HAI "Akigssek" ("Grouse") crashed about south of
Nuuk, resulting in the loss of 15 lives. It was en route to
Paamiut from
Nuuk. The same aircraft had an emergency landing on the
Kangerlussuaq fjord two years earlier, due to flameout on both engines because of ice in the intake. • On 10 May 1974 a
KLM Helikopters S-61N, registration PH-NZC, crashed en route to an oil rig in the
North Sea. None of the six people on board (two crew and four passengers) survived. The probable cause was a failure in one of five rotor blades due to
metal fatigue. The resulting imbalance caused the motor mounts to fail and caused a fire. The uncontrollable aircraft landed hard in the water, capsized and sank. Investigation indicated that the metal fatigue crack must have spread rapidly in less than four hours. The rotor blades are pressurized with
nitrogen gas at to indicate the onset of a metal fatigue failure, yet no pressure loss was indicated during the preflight inspection. As a result of the accident, it was recommended to shorten inspection intervals. The aircraft was recovered from the North Sea floor. It was sold to Carson Helicopter in the U.S. and re-registered as N87580. • On 16 May 1977, a
New York Airways commercial S-61-L, N619PA, suffered a static rollover onto its starboard side at the heliport on top of the
Pan Am Building while boarding passengers. The accident killed four boarding passengers, including filmmaker
Michael Findlay, and one woman on the street. Seventeen additional passengers and the three flight crew members were uninjured. The landing gear collapse resulted from metal fatigue in the helicopter's main landing gear shock-absorbing strut assembly, which caused the helicopter to tip over without warning. The accident resulted in the permanent closure of the Pan Am Building heliport. As the heliport was closed, the wreckage was removed by disassembling it and taking the assemblies down to street level using the building's freight elevators. The airframe was taken to Cape Town, South Africa, where it was rebuilt, certified and returned to service for the Ship-Service Role off the shores of the
Western Cape by the company "Court Helicopter" which was later amalgamated with CHC.
1980s • On 16 July 1983,
British Airways Helicopters' commercial S-61 G-BEON
crashed in the southern
Celtic Sea, in the
Atlantic Ocean, en route from
Penzance to
St Mary's, Isles of Scilly, in thick fog. Only 6 of the 26 on board survived. It sparked a review of helicopter safety and was the worst civilian helicopter disaster in the UK until 1986. • On 20 March 1985, an Okanagan Helicopters S-61N (C-GOKZ) ditched in the Atlantic Ocean off
Owls Head,
Nova Scotia. The aircraft was en route from the MODU Sedco 709 offshore Nova Scotia to the
Halifax International Airport (YHZ) when the main gearbox suffered a total loss of transmission fluid. There were 15 passengers and 2 crew on board. There were no injuries during the ditching; however, several passengers suffered varying degrees of
hypothermia. As a result of this incident, improved thermal protection and other advancements in helicopter transportation suits were instituted for offshore workers on Canada's east coast. • On 13 July 1988, a
British International Helicopters S-61N, registration G-BEID, suffered an engine failure and fire and
ditched into the North Sea. There were no injuries.
1990s • On 25 July 1990, a
British International Helicopters S-61, registration G-BEWL, from
Sumburgh Airport crashed onto the
Brent Spar oil storage platform as the pilots attempted to land. The aircraft fell into the North Sea, where 6 of the 13 passengers and crew on board died.
2000s • On 8 July 2006, a
Sociedad de Salvamento y Seguridad Marítima S-61N Mk.II
search and rescue helicopter, crashed into the
Atlantic Ocean while flying from
Tenerife to
La Palma. There were no survivors among the six people on board. • On 5 August 2008, two pilots and seven firefighters assigned to the Iron Complex fire in California's
Shasta–Trinity National Forest, were killed when
Carson Helicopters' S-61N N612AZ crashed on takeoff. Of the thirteen people reportedly on board, one other pilot and three firefighters survived the crash with serious or critical injuries. The
NTSB determined that the probable causes were the following actions by Carson Helicopters: 1) the intentional understatement of the helicopter's empty weight, 2) the alteration of the power available chart to exaggerate lift capability, and 3) the use of unapproved above-minimum specification torque in performance calculations that, collectively, resulted in the pilots’ relying on performance calculations that significantly overestimated load-carrying capacity and without an adequate performance margin for a successful takeoff; and insufficient oversight by the U.S. Forest Service and the Federal Aviation Administration. Contributing factors were the flight crew's failure to address the fact that the helicopter had approached its maximum performance capability on two prior departures from the accident site, as they were accustomed to operating at its performance limit. Contributing to the fatalities were the immediate, intense fire due to a fuel spillage upon impact from the fuel tanks that were not crash-resistant, the separation from the floor of the cabin seats that were not crash-resistant, and the use of an inappropriate release mechanism on the seat restraints.
2020s • On 22 February 2022, an S-61N being flown by
Croman Corporation in support of a training operation, crashed and killed the four occupants, at the
Pacific Missile Range Facility on the
Hawaiian island of
Kauai. ==Specifications (S-61N Mk II)==