Wheels-Up Landing: Continental Airlines Flight 1943
On February 19, 1996, a Continental Airlines DC-9 landed wheels-up on runway 27 at Houston Intercontinental Airport. The NTSB determined that the captain failed to turn on the hydraulics, so that hydraulic pressure was not available to lower the landing gear or deploy the flaps. Although the flightcrew eventually realized that the flaps were not extended, they continued the approach anyway and were so preoccupied with the flap problem that they failed to perform the landing checklist or to detect the failure of the landing gear to extend. Here are the NTSB’s findings and recommendations.
PB97-910401 NTSB/AAR-97/01
NATIONAL TRANSPORTATION SAFETY BOARD
WASHINGTON, D.C. 20594
AIRCRAFT ACCIDENT REPORT
WHEELS-UP LANDING
CONTINENTAL AIRLINES FLIGHT 1943
DOUGLAS DC-9 N10556
HOUSTON, TEXAS
FEBRUARY 19, 1996
EXECUTIVE SUMMARY
On February 19, 1996, at 0902 Central Standard Time, ContinentalAirlines (COA) flight 1943, a Douglas DC-9-32, N10556, landedwheels up on runway 27 at the Houston Intercontinental Airport,Houston Texas. The airplane slid 6,850 feet before coming to restin the grass about 140 feet left of the runway centerline. Thecabin began to fill with smoke, and the captain ordered the evacuationof the airplane There were 82 passengers, 2 flightcrew members,and 3 flight attendants aboard the airplane. No fatal or seriousinjuries occurred; 12 minor injuries to passengers were reported.The airplane sustained substantial damage to its lower fuselage.The regularly scheduled passenger flight was operating under Title14 Code of Federal Regulations Part 121 and had originated fromWashington National Airport 3 hours before the accident. An instrumentflight rules flight plan had been filed; however, visual meteorologicalconditions prevailed for the landing in Houston.
The National Transportation Safety Board determines that the probablecause of this accident was the captain's decision to continuethe approach contrary to COA standard operating procedures thatmandate go-around when an approach is unstabilized below 500 feetor a ground proximity warning system al continues below 200 feetabove field elevation. The following factors contributed to theaccident: (1) the flightcrew's failure to properly complete thein-range checklist, which resulted in a lack of hydraulic pressureto lower the landing gear and deploy the flaps; (2) the flightcrew'sfailure to perform the landing checklist and confirm that thelanding gear was extended; (3) the inadequate remedial actionsby COA ensure adherence to standard operating procedures; and(4) the Federal Aviation Administration's (FAA) inadequate oversightof COA to ensure adherence to standard operating procedures.
Safety issues discussed in this report include checklist design,flightcrew training, adherence to standard operating procedures,adequacy of FAA surveillance, and flight attendant tailcone training.Safety recommendations concerning these issues were made to theFAA.
CONCLUSIONS
Findings
- The two-member flightcrew and three flight attendants weretrained and qualified to conduct the flight accordance with Federalregulations. There was no evidence of any medical condition thatmight have affected the flightcrew's performance.
- The air traffic control request to maintain 190 knots to theouter marker did not contribute to the accident because it didnot affect crew actions, decisionmaking, or situational awareness.
- The airplane was certificated and equipped and maintainedin accordance with Federal regulations approved procedures. Thereis no evidence that mechanical malfunctions or failures of theairplane structures, flight control systems, or powerplants contributedto the accident.
- Because the captain omitted the "Hydraulics" itemon the in-range checklist and the first officer failed to detectthe error, hydraulic pressure was not available to lower the landinggear and deploy the flaps.
- The "Hydraulics" item is placed too low on the in-rangechecklist, rendering it vulnerable to omissions.
- The captain's distraction from his duties as pilot-in-commandand his disregard for the sterile cockpit rule contributed tothe pilots' failure to detect their hydraulic system configurationerror when they selected 5º of flaps.
- Both the captain and the first officer recognized that theflaps had not extended after the flaps were selected to 15º.
- The pilots' lack of previous exposure, either through trainingor during line operations, to the consequences of improper hydraulicsystem configuration contributed to their failure to detect theirhydraulic system configuration error.
- The pilots failed to perform the landing checklist and todetect the numerous cues alerting them to the status of the landinggear because of their focus on coping with the flap extensionproblem and the high level of workload as a result of the rapidsequence of events in the final minute of the flight.
- Had the landing checklist been properly performed, the flightcrewwould have detected the failure the landing gear to extend.
- Although the first officer was unwilling to overtly challengethe captain's decision to continue the approach, he did attemptto communicate his concern about the excessive speed of the approachto the captain.
- There was no compelling reason for the captain's decisionto land the airplane; multiple signals and guidance indicatedthat the approach should be discontinued, as did Continental Airlines'standard operating procedures.
- The flightcrew's degraded performance is consistent with theeffects of fatigue, but there is insufficient information to determinethe extent to which it contributed to the accident.
- There were deficiencies in Continental Airlines' (COA) oversightof its pilots and the principal operations inspector's oversightof COA. COA was aware of inconsistencies in flightcrew adherenceto standard operating procedures within the airline; however,corrective actions taken before the accident had not resolvedthis problem.
- This accident demonstrates the need for all air carriers tobring their checklists that apply to all phases of ground andflight operations into compliance with the contemporary humanfactors principles of checklist design outlined in the FAA's report,"Human Performance Considerations in the Use and Design ofAircraft Checklists."
- The "C" flight attendant was unable to completelyremove the tailcone access plug door, because one of the aft jumpseatshoulder harness straps was buckled to the lap belt, which tiedthe plug door to the cabin bulkhead. Fortunately, the lack ofavailability of the tailcone exit did not preclude a timely andsuccessful evacuation.
- Continental Airlines flight attendants received inadequateinformation and training on the operation of the DC-9 tailconeaccess plug door.
Probable Cause
The National Transportation Safety Board determines that the probablecause of this accident was the captain's decision to continuethe approach contrary to Continental Airlines (COA) standard operatingprocedures that mandate a co-around when an approach is unstabilizedbelow 500 feet or a ground proximity warning system alert continuesbelow 200 feet above field elevation. The following factors contributedto the accident: (1) the flightcrew's failure to properly completethe in-range checklist, which resulted in a lack of hydraulicpressure to lower the landing gear and deploy the flaps; (2) theflightcrew's failure to perform the landing gear checklist andconfirm the landing gear was extended; (3) the inadequate remedialactions by COA to ensure adherence to standard operating procedures;(4) the Federal Aviation Administration's inadequate oversightof COA to ensure adherence to standard operating procedures.
RECOMMENDATIONS
As a result of the investigation of this accident, the NationalTransportation Safety Board makes the following recommendationsto the Federal Aviation Administration:
Require all DC-9 and MD-80 operators with the "HI, LOW, OFF"hydraulic switch configuration to revise their checklists to emphasizethe importance of the "Hydraulics" item by placing itas the first item on the in-range checklist (or equivalent), andrequiring that both pilots verbally verify hydraulic pump switchsettings and system pressures. (A-97-3)
Require all principal operations inspectors of 14 CFR Part 121operators using DC-9 and MD-80 airplanes with the "HI, LOW,OFF" hydraulic switch configuration to ensure that operatingmanuals and training programs include information about the consequencesof improper hydraulic system configuration, specifically thatthe flaps and landing gear will not function normally if the engine-drivenhydraulic pumps are not set to "HI." (A-97-4)
Require all principal operations inspectors of 14 CFR Part 121carriers to ensure that the carriers establish a policy and makeit clear to their pilots that there will be no negative repercussionsfor appropriate questioning in accordance with crew resource managementtechniques of another pilot's decision or action. (A-97-5)
Require all principal operations inspectors of 14 CFR Part 121carriers to ensure that crew resource management programs providepilots with training in recognizing the need for, and practicein presenting, clear and unambiguous communications of flight-relatedconcerns. (A-97-6)
Require Continental Airlines to audit its internal oversight processand correct deficiencies in that oversight process that allowdeviations from standard operating procedures and violations ofFederal regulations to go uncorrected, and to develop a specificplan to reinforce the importance of adherence to standard operatingprocedures among pilots. (A-97-7)
Audit its surveillance of Continental Airlines (COA) en routeoperations to determine if the surveillance is adequate to identifyprocedural deficiencies in COA s operations. (A-97-8)
Require that principal operations inspectors review the checklistsof air carriers operating under 14 CFR Parts 121 and 135 to ensurethat they comply with the guidance presented in the Federal AviationAdministration report entitled "Human Performance Considerationsin the Use and Design of Aircraft Checklists," and requirethat any checklists that do not comply with the guidance be revisedaccording (A-97-9)
Amend Flight Standards Handbook Bulletin 96-02, "Guidelinesfor Crewmember Training on Aircraft Tailcones and Approval ofTailcone Training Devices," to include a requirement thatif any portion of a restraint system is attached to the tailconeaccess plug door in the aircraft that might interfere with theopening of the door, the plug door training device must be equippedwith the entire restraint system. (A-97-10)
BY THE NATIONAL TRANSPORTATION SAFETY BOARD
JAMES E. HALL
Chairman
ROBERT T. FRANCIS II
Vice Chairman
JOHN A. HAMMERSCHMIDT
Member
JOHN J. GOGLIA
Member
GEORGE W. BLACK
Member
