Map Etihad Airways Official website: 12 photos and 1 tip from 38 visitors to Thai Airways Flight TG 417 BKK-KUL. Etihad Airways Reservation Office telephone contact numbers: +1 8. Etihad Airways Los Angeles Reservation Office Office Address: Los Angeles, United States of America. Etihad Airways is The National Airline of the United Arab Emirates.
The accident happened when the (arbitrarily designated) yellow blade, one of five main rotor blades, separated at the spindle which attached the blade to the rotor head. According to the National Transportation Safety Board the probable cause of the accident was fatigue failure. The aircraft was destroyed by impact and fire. All eighteen passengers and three crew members were killed.
The flight, operating under Visual Flight Rules was cleared by Air traffic control to take off and proceed eastbound at 10:28:15. The aircraft and crew had completed three round trips to various destinations in the Greater Los Angeles Metropolitan Area beginning at 0607 PDT and departed the ramp at Los Angeles for Flight 417 at 1026. ContentsLos Angeles Airways (LAA) Flight 417, piloted by Captain Kenneth Lee Waggoner, former USMC helicopter pilot, was a regularly scheduled passenger flight from Los Angeles International Airport to the Disneyland Heliport in Anaheim, California. The fatigue crack originated in an area of substandard hardness and inadequate shot peening.
Statements were obtained from 91 witnesses. This was the last known radio contact with the flight. The flight acknowledged, "Four seventeen thank you". Four seventeen, seven miles east, radar service terminated". At 10:32:55 Air Traffic Control advised, "L.A.
Most witnesses indicated the flights at 370 metres (1,200 ft) to 460 metres (1,500 ft) appeared to be most accurate. In order to establish an approximate altitude for the flight, several comparative flights were conducted in a similar helicopter. As the helicopter fell in variously described gyrations, the tail cone either folded or separated. A main rotor blade was either observed to separate or was seen separated in the vicinity of the main rotor disc.
It is estimated that approximately 3.17 hours were flown on August 14, 1968. AircraftN300Y, a Sikorsky S-61L helicopter, serial number 61031 was the prototype for the S-61L, and had accumulated 11,863.64 total flying hours prior to the day of the accident. Examination of the yellow blade spindle (S/N AJ19) revealed a fatigue fracture in the shank of the spindle adjacent to the shoulder in the inboard end of the shank. Minor parts associated with this rotor blade were scattered over a three-block area northwest of the park. The fifth main rotor blade (yellow) including the sleeve and part of spindle, was located approximately 400 metres (0.25 mi) north-west of the main wreckage site. The entire fuselage, both engines, main rotor head assembly, four main rotor blades, and the pylon assembly were located in the main impact area.
FindingsIn the course of the investigation by the National Transportation Safety Board (NTSB) they made the following findings: The estimated gross weight at the time of the accident was 7,765 kilograms (17,118 lb). The allowable limits are from 650 to 708 centimetres (256.0 to 278.7 in) for a gross weight of 7,700 kilograms (17,000 lb). The computed centre of gravity at the time of the accident was 660.68 centimetres (260.111 in) from datum, which is 679 centimetres (267.4 in) forward of the main rotor hub centerline. The aircraft was serviced with 450 kilograms (1,000 lb) of JP-4 fuel and had a takeoff gross weight of 7,795 kilograms (17,185 lb), which was below the maximum allowable takeoff weight of 8,600 kilograms (19,000 lb).
Metal hardness below specifications associated with a banded microstructure. The crack initiated because of a combination of the following factors: The fatigue crack was a high-cycle, low-stress type which propagated over a long period of time. Blade separation was due to fatigue failure of the spindle. The yellow main rotor blade separated in flight rendering the aircraft uncontrollable. The crewmembers were qualified for the flight.
Los Angeles Airways Flight 417 Manual For The
The directive has since been amended twice and now requires the following action: (a) Before further flight, remove main rotor blade spindles P/Ns S6110-23325-1, S6110-23325-2, and S6112-23025-1 that either have been "salvaged" in accordance with procedures set forth in paragraph entitled "Salvage of Spindle" contained in Sikorsky Aircraft Overhaul Manual for the pertinent helicopter model, or have accumulated 3000 or more hours' time in service on the effective date of this AD, and replace with blade spindles of the same part number that have not been "salvaged" and that have less than 3000 hours' time in service.(b) Replace main rotor blade spindles P/Ns S6110-23325-1, S6110-23325-2, and S6112-23025-1, that have not been "salvaged" and have less than 3000 hours' time in service on the effective date of this AD, before the accumulation of 3000 hours' time in service with main rotor blades spindles of the same part number that have not been "salvaged" and have less than 3000 hours' time in service.(c) Before further flight, remove from service main rotor blade spindles P/N's S6110-23325-1, S6110-23325-2, and S6112-23025-1, serial numbers AX51, AX54, F2148, F2444, F2485, F2207, F1406, F1416, F1415, F1399, B-35, and F2451. It is believed that the crack was present at the last Magnaglo inspection of the part, and it is not known why it was not detected.Following the initial evidence of a metal fatigue type failure, the National Transportation Safety Board recommended on Augto the Federal Aviation Administration: Based on its preliminary findings in the Compton crash investigation, the Safety Board today is recommending to the Federal Aviation Administrator that he (1) require an immediate fleet inspection of all Sikorsky S-61 helicopter spindle units (2) adopt a more precise and frequent inspection to preclude future spindle unit failures and (3) study the need for establishing a retirement life for this vital part.On the same date the FAA issued Emergency Airworthiness Directive 68-19-07. Pitting that may have been present in the base metal surface. Possible detrimental effect of residual tensile stress from the plating.
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