The committee investigating the helicopter crash in which two Air Force pilots, Lt. Col. Erez Sahiani, and Major Chen Fogel were killed, has submitted an interim report.
Interim findings indicate that the team handled a complex emergency for about two minutes until impact with the water. The incident occurred due to an internal failure in the left engine, which later caused a fire to ignite and smoke to penetrate the crew compartment. The spread of the fire also caused damage to the right engine.
As a result of the damage to both engines, the helicopter quickly lowered and hit the water hard. The intensity of the impact with the water left the pilots unconscious, and no actions were identified that indicated an attempt to escape. It was determined that the pilots drowned.
An inspection of the helicopter engine by the manufacturer revealed that the technical failure of the left engine was due to hot corrosion in an internal component, which led to the formation of a fatigue crack in the engine turbine blade, which developed during flight and eventually caused a fire to develop abnormally. It should be noted that the engine was last inspected by the manufacturer in 2017, in accordance with procedures stipulating that an inspection be carried out every 1650 engine hours.
Less than 1,400 hours had passed since the last inspection of the engine until the accident. In addition, about a year ago, the helicopter underwent a comprehensive inspection in Israel and was found to be in good condition. According to the manufacturer, this malfunction was the first of its kind in the world. The reason for the formation of hot corrosion in the internal component of the engine is still being examined. Inspection and repair of the internal components of the engine, are being carried out only by the manufacturer.
The operation of the crew included the diagnosis of the malfunction, the activation of the fire extinguishing systems, the disconnection of some of the electrical systems in order to prevent the continued penetration of smoke into the crew cell, and the activation of buoyancy systems.
The investigating team found that the pilots handled the incident calmly, with continuous teamwork, with rapid diagnosis and with attempts to respond to changes. It was further found that the pilots did not turn off the engine before operating the fire extinguishing tanks and thus the efficiency of the extinguishing systems was reduced.
The crew continued to fly the helicopter until the moment it hit the water, thus contributing to the rescue of Captain Ron Birman. The helicopter overturned a few seconds later. The crew operated the buoyancy systems, but these systems are not designed to deal with such an impact hit and so the right buoy exploded. The tail assembly broke, the naval patrol officer's door opened and the helicopter began to sink.
Within eight minutes of losing contact with the helicopter, rescue operations began and forces from the Air Force, Navy and Israel Police were dispatched. Under the conditions of this accident, the pilots could not be rescued. Captain Birman was rescued alive.
The Air Force Commander received the interim findings and the committee's recommendations to continue the inspection process, including a gradual return of the Atalef helicopters to flight, and tto continue the inspection process on technical issues, helicopter maintenance, literature, training, instruction, control and more.
The Air Force Commander concluded: "Since the accident there has been a cross-continental effort, with no resource limit, with a variety of consultants, civilian companies, test pilots and the manufacturer in France to understand in depth the circumstances of the accident. We found no failure in the continual maintenance process. The Atalef if a helicopter that has flown for many years, and its engines are common in the world and are not associated with unusual accidents. Each accident is preventable, and we understand that the cause of the accident was a technical malfunction.We will continue to investigate and improve and do as much as possible to prevent recurrence of such incidents."
"The late Lt. Col. Erez Sahiani, Deputy Commander of the Ramat David Base, and the late Major Chen Fogel, Deputy Commander of the Meginei Hama'arav Squadron, both pilots and senior Air Force commanders, professional and experienced, who performed many training and operational activities and accumulated thousands of flight hours, held command and combat roles and contributed greatly to the security of the State of Israel. The pilots performed emergency and escape drills that trained them to deal with extreme events. The crew dealt with a malfunction and a sequence of events in the air in a short time, calmly and with teamwork, and their actions resulted in the helicopter hitting the water in a way that enabled Captain Ron Birman to be rescued."