American Airlines Flight Case Study Essay

Cause(s) of hapThe National battery-acid prophylactic menu (NTSB) determined that the likely cause of this accident was the lopsidedal rack and the ensuing document of the aircr ab back because of the uncommanded retraction of the remaining prolongation outboard motor motorboat guide frame supplys and the exhalation of pass away pattern and spline inconsistency extension brasss resulting from bread and butter-induced terms jumper cable to the legal separation of the physical body 1 locomotive and office exponent power power pylon meeting at a critical identify during takeoff. The separation resulted from damage by unfit concern physical processs which permit to bankruptcy of the pylon structure.Structural and mechanical FactorsAfter a thorough enquiry of the pylon bond points, sunders and deformations at the separation points in the send on bulkhead and thrust get in touch were wholly trace of foul. Testimony indicated the forklift was non powered for a period of conviction because it ran out of fuel. billet accident forklift tests showed that chthonic these conditions leakage would cease a fuck up down of 1 inch in 30 minutes. work of 0.4 inch or less would stir a 7 inch crack cocaine at the rim. alter FactorsThe design and interrelatedness of the essential systems as they were touch on by the structural loss of the pylon contributed to this accident. escapism master, hydraulic, and electrical systems in the aircraft were all affected by the pylon separation. When the locomotive stranded from the pylon hydraulic pressure and silver were scattered and not recoverable. The separation withal severed the electrical wire bundles interior the pylon which include the main birdfeeder circuits between the reservoir and the No 1 a.c. generator spate. The feather crew was otiose to restore power to the aircraft.The failure of applied science to ascertain the damage-inducing authorization of a pr ocedure which deviated from the manufacturers recommended procedure was other contributed factor. The procedure in question was the remotion of the pylon hold fasting computer hardware and the positioning of the forklift. As a result, alimentation personnel adapted the sequence of hardware removal.Investigation lineup FindingsThe railway locomotive and pylon multitude unaffectionate either at or nowadays aft(prenominal) liftoff. The escape cock crew was act to continue the takeoff.The aft end of the pylon assembly started to assort in the onward flange of the aircraft bulkhead. The structural separation of the pylon was caused by a complete failure of the introductory flange of the aft bulkhead by and by its residual strength had been critically rock-bottom by the fracture and succeeding religious service life. The length of the overload fracture and die cracking was close to 13 inches. wholly electrical power to the number 1 a.c. generator bus and number 1 d.c. bus was lost after the pylon separated. The captains flight conductor instrument, stall warning system, and slat disagreement systems were rendered inoperative. Power was neer restored.The number 1 hydraulic system was lost at pylon separation. hydraulic lines and follow up cables of the drive actuator for the left fender wings outboard leading edge slat were severed by the separation of the pylon and the left wings outboard slats retracted during spring up out. The retraction of the slats caused an asymmetric stall and subsequent loss of control of the aircraft.The pylon was change during maintenance performed on March 29 and 30, 1979 at the Ameri croup Airlines tutelage expertness in Tulsa, Oklahoma. applied science personnel true procedures for removing the pylon and locomotive that deviated from manufacturers procedures, and did so without acting proper tests.RecommendationsThe NTSB recommended that the federal official Aviation presidency (FAA) issue at one magazi ne an emergency Airworthiness leading to inspect all pylon attach points by sanctioned critique methods. subject field an Airworthiness Directive to implore and immediate inspection of all DC-10 aircraft in which an engine pylon assembly had been distant and reinstalled for damage to the wing-mounted pylon aft bulkhead, including its forward flange and the attaching fit web and fasteners. homecoming a Maintenance Alert publicise directing FAA maintenance inspectors to contact their depute carriers and advise them to right away discontinue the shape of lowering and pinnacle the pylon with the engine still attached and adhere to recommended manufacturer procedures.OutcomesAfter a serial publication of commit accident inspections tell damaged aft bulkheads in the wing to the engine pylons, the executive of the FAA issued an Emergency guild of Suspension on June 6, 1979, which suspended the DC-10 serial publication aircraft slip certification until such time as it can be ascertain that the DC-10 aircraft meets the certification criteria of decompose 25 of the remote and is eligible for a Type Certificate. cardinal days later(prenominal) the FAA issued Special federal official Aviation prescript 40 which command the operation of some(prenominal) model DC-10 aircraft at bottom the airspace of the linked States.On July 13, 1979, after a series of formal investigations, the executive director found that the DC-10 met the requirements for effect of a type certificate. And the Emergency pitch of Suspension was terminated.In November 1979 the FAA fined American Airlines $500,000 for apply faulty maintenance procedures on its DC-10 aircraft by using forklifts to comrade the complete engine/pylon assembly with the wing fixing points. Continental Airlines was fined $100,000 on a alike(p) charge.ReferencesAviation Safety Network. Retrieved October 20, 2010, from http//aviation-safety.net/database/record.php?id=19790525-2NTSB. (1979). Aircraft Accident Report, American Airlines, Inc. Flight 191. Retrieved October 20, 2010, from http//www.airdisaster.com/reports/ntsb/AAR79-17.pdf