Yas'ur
1977-MAY-10 · Jordan Valley, West Bank

Israeli Air Force — Flight Yas'ur 360

An Israeli Air Force Sikorsky CH-53 Sea Stallion crashed into a hillside in the Jordan Valley during a night-time military exercise, killing all 54 personnel on board. The accident, known in Israel as 'Ason Hanun-Dalet' (Disaster of the 54), remains one of the deadliest aviation accidents in the history of the Israel Defense Forces.

Aircraft
Sikorsky CH-53 Sea Stallion
Registration
360
Phase
Cruise
Cause
Controlled Flight Into Terrain (CFIT)
Souls on Board
54
Fatalities
54
Origin → Dest
? → ?
Report
Final

Investigation Summary

The aircraft, an S-65C-3 Yas'ur, was participating in a large-scale military exercise in the Jordan Valley. During the dark hours of the night, the helicopter was flying at a low altitude as part of tactical maneuvers. While en route, the aircraft struck a hill in the Jebel Qarantal (Mount of Temptation) area, approximately 10 kilometers west of the Jordan River. The impact was catastrophic, resulting in the total destruction of the airframe and a post-crash fire. The investigation determined that the flight crew had descended below the minimum permissible altitude for the area and conditions, leading to a classic Controlled Flight Into Terrain (CFIT) scenario. The victims included 10 crew members and 44 paratroopers.

Final Conclusions

The official investigation concluded that the primary cause was pilot error. The pilot operated the helicopter below the authorized safety altitude during night-time conditions, which provided insufficient clearance from the rising terrain in the Jordan Valley.

Video Analysis

No video analysis linked for this case file yet.

Systems & Failure Modes

i

Altimeter

The crew failed to maintain the minimum safe altitude required for night operations over the Jordan Valley terrain.

Interesting Facts

  • 01The accident is known in Israel as 'Ason Hanun-Dalet' or the 'Disaster of the 54'.
  • 02All 54 people on board, including 44 paratroopers and 10 crew members, were killed.
  • 03The crash occurred during a night-time military exercise in the West Bank.
  • 04The aircraft involved was a Sikorsky S-65C-3 Yas'ur with registration 360 and MSN 65-351.

Safety Actions & Advisories

Flight Altitude Restrictions

Following the disaster, the IAF reviewed and tightened regulations regarding minimum flight altitudes during night-time exercises to prevent CFIT accidents.

Location

Jordan Valley, West Bank · 31.9321, 35.4365

Case File History

  1. CorrectionUpdated investigation summary and event timeline.

Related Cases

Case ID · iaf-ch53-1977Last updated · Filed

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