Mentour Pilot recounts the 1992 El Al flight 1862 accident: the aircraft, the crew, the pylon fuse pins, the failures and the aftermath.
What the video covers
Written in our own words. It only describes what the video shows and says.The flight and crew
Mentour Pilot describes a Boeing 747 climbing above Amsterdam on 4 October 1992. He states that El Al flight 1862 was scheduled from New York JFK Airport to Tel Aviv Ben Gurion Airport with a stopover at Amsterdam Schiphol Airport. The aircraft was a Boeing 747-258 with registration 4X-AXG, delivered in 1979, with just over 45,000 flight hours and roughly 10,000 pressurization cycles. He gives crew details: a 59 year old captain with 25,000 hours, a 32 year old first officer with 4,288 hours, and a 61 year old flight engineer with more than 26,000 hours. A 23 year old El Al employee was jump seating. The first officer was pilot flying, and the aircraft departed runway 01 left at 18:21 after a 50 minute delay.
The pylon and fuse pin design
Mentour Pilot explains that the 747 engine is attached to the wing through a pylon, which carries weight, thrust, drag and aerodynamic loads. He describes fuse pins as deliberately weak attachment points intended to fail first under overload, allowing an engine to separate rather than damage the wing. On the 747, four pins were installed: one forward, one aft and two at the midpoint. He says the forward and aft pins were weaker and should fail before the middle pins. He states that the 747-200 pylon design evolved from the Boeing 707 and was certified using 707 test data. He says Boeing designed for two separate failure modes, load redistribution and controlled engine separation, and that no full scale pylon fatigue testing had been conducted.
Crack growth, failure and response
Mentour Pilot says investigators concluded that cracking most likely began inside the inboard midspar fuse pin. The cracks grew from the inside outwards, and ultrasonic testing was difficult because bore geometry and crack orientation reduced reflections. He says inspections on 17 June 1992 assessed the pins as acceptable. During climb through about 6,500 feet, turbulence fractured the pin, then the load concentrated on one outboard lug, which failed, followed by the forward and aft pins. The number three engine struck the number four engine, and both engines separated, tearing away leading edge from about one metre inboard of engine three to one metre outboard of engine four. Hydraulic lines ruptured, pneumatic systems failed, and Krueger flaps were lost. The captain took control, the first officer made a mayday call, and the crew requested runway 27. He says the aircraft slowed below about 260 knots, rolled right, and crashed at 18:35:25 into an 11 storey apartment complex in the Bijlmermeer district. All four people on board and at least 43 residents were killed. Within a month, the Federal Aviation Administration issued an emergency airworthiness directive requiring operators of Boeing 747 and 707 aircraft to remove and replace existing fuse pins within 30 days. Ultrasonic inspection procedures were revised, and in 1995 the FAA mandated the Boeing 747 Strut Modification Program, introducing stronger load paths, improved corrosion resistance, redesigned fuse pins, titanium midspar fittings and additional redundancy in the wing box.
