NTSB accident report

213 Pages·2010·5.72 MB·English

Loss of Thrust in Both Engines After Encountering a Flock of 
Birds and Subsequent Ditching on the Hudson River 
US Airways Flight 1549 
Airbus A320‐214, N106US 
Weehawken, New Jersey 
January 15, 2009 

Accident Report
NTSB/AAR-10/03
PB2010-910403
National

Transportation

Safety Board

NTSB/AAR-10/03
PB2010-910403
Notation 8082A
Adopted May 4, 2010

Aircraft Accident Report
Loss of Thrust in Both Engines After Encountering a Flock of
Birds and Subsequent Ditching on the Hudson River
US Airways Flight 1549
Airbus A320-214, N106US
Weehawken, New Jersey
January 15, 2009

National
Transportation
Safety Board

490 L’Enfant Plaza, S.W.
Washington, D.C. 20594
National Transportation Safety Board. 2010. Loss of Thrust in Both Engines After Encountering a
Flock of Birds and Subsequent Ditching on the Hudson River, US Airways Flight 1549, Airbus
A320-214, N106US, Weehawken, New Jersey, January 15, 2009. Aircraft Accident Report
NTSB/AAR-10 /03. Washington, DC.

Abstract: This report describes the January 15, 2009, accident involving the ditching of US Airways
flight 1549 on the Hudson River about 8.5 miles from LaGuardia Airport, New York City, after an almost
complete loss of thrust in both engines following an encounter with a flock of birds. The 150 passengers,
including a lap-held child, and 5 crewmembers evacuated the airplane by the forward and overwing exits.
One flight attendant and four passengers were seriously injured, and the airplane was substantially
damaged.

Safety issues discussed in this report include in-flight engine diagnostics, engine bird-ingestion
certification testing, emergency and abnormal checklist design, dual-engine failure and ditching training,
training on the effects of flight envelope limitations on airplane response to pilot inputs, validation of
operational procedures and requirements for airplane ditching certification, and wildlife hazard
mitigation. The report also discusses survival-related issues, including passenger brace positions;
slide/raft stowage; passenger immersion protection; life line usage; life vest stowage, retrieval, and
donning; preflight safety briefings; and passenger education. Safety recommendations concerning these
issues are addressed to the Federal Aviation Administration, the U.S. Department of Agriculture, and the
European Aviation Safety Agency.

The National Transportation Safety Board (NTSB) is an independent federal agency dedicated to promoting
aviation, railroad, highway, marine, pipeline, and hazardous materials safety. Established in 1967, the agency is
mandated by Congress through the Independent Safety Board Act of 1974 to investigate transportation accidents,
determine the probable causes of the accidents, issue safety recommendations, study transportation safety issues, and
evaluate the safety effectiveness of government agencies involved in transportation. The NTSB makes public its
actions and decisions through accident reports, safety studies, special investigation reports, safety recommendations,
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Washington, DC 20594
[phone] or [phone]

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The Independent Safety Board Act, as codified at 49 U.S.C. Section 1154(b), precludes the admission into evidence
or use of NTSB reports related to an incident or accident in a civil action for damages resulting from a matter
mentioned in the report.
NTSB Aircraft Accident Report
Contents
Figures .......................................................................................................................................... vii 
Tables .......................................................................................................................................... viii 
Abbreviations ............................................................................................................................... ix 
Executive Summary .....................................................................................................................xv 
1. Factual Information ...................................................................................................................1 
1.1 History of Flight .........................................................................................................................1 
1.2 Injuries to Persons ......................................................................................................................6 
1.3 Damage to Airplane ...................................................................................................................6 
1.4 Other Damage ............................................................................................................................6 
1.5 Personnel Information ................................................................................................................6 
1.5.1 The Captain ......................................................................................................................6 
1.5.1.1 The Captain’s 72-Hour History .........................................................................7 
1.5.2 The First Officer ..............................................................................................................8 
1.5.2.1 The First Officer’s 72-Hour History ..................................................................8 
1.5.3 The Flight Attendants ......................................................................................................9 
1.6 Airplane Information .................................................................................................................9 
1.6.1 General Information .........................................................................................................9 
1.6.2 Airspeed Displays ..........................................................................................................10 
1.6.3 Flight Envelope Protections ...........................................................................................12 
1.6.4 Low-Speed or -Energy Warning ....................................................................................12 
1.6.5 Electrical and Hydraulic Systems ..................................................................................13 
1.6.6 Engines ..........................................................................................................................13 
1.6.6.1.1 Requirements at the Time of Certification............................................. 16 
1.6.6.1.2 Amendments Made After Certification ................................................. 18 
1.6.6.1.3 Postaccident Actions .............................................................................. 20 
1.6.7 Airframe Ditching and Emergency Landing Certification Requirements .....................20 
1.6.8 US Airways Maintenance Program ...............................................................................23 
1.6.8.1 General .............................................................................................................23 
1.6.8.2 Engine Maintenance Records ..........................................................................23 
1.7 Meteorological Information .....................................................................................................24 
1.8 Aids to Navigation ...................................................................................................................24 
1.9 Communications ......................................................................................................................24 
1.10 Airport Information ................................................................................................................25 
1.10.1 FAA Guidance on Airport Wildlife Hazard Management ..........................................25 
1.10.2 LGA Wildlife Hazard Management Program ..............................................................26 
1.10.3 Air Traffic Control .......................................................................................................26 
1.10.3.1 ATC Guidance ...............................................................................................27 
1.10.3.2 Traffic Conflict ..............................................................................................28 
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NTSB Aircraft Accident Report
1.10.3.3 Airport Surveillance Radar ............................................................................29 
1.11 Flight Recorders .....................................................................................................................29 
1.11.1 Cockpit Voice Recorder ..............................................................................................29 
1.11.2 Flight Data Recorder ....................................................................................................30 
1.12 Wreckage and Impact Information ........................................................................................30 
1.12.1 Structural Damage .......................................................................................................30 
1.12.2 Engine Damage ............................................................................................................33 
1.13 Medical and Pathological Information ...................................................................................35 
1.14 Fire .........................................................................................................................................36 
1.15 Survival Aspects ....................................................................................................................36 
1.15.1 Ditching Requirements ................................................................................................36 
1.15.1.1 Emergency Exits ............................................................................................36 
1.15.1.2 Safety Equipment ...........................................................................................37 
1.15.2 Preflight Briefing Requirements ..................................................................................38 
1.15.3 Safety Information Card Requirements .......................................................................39 
1.15.4 US Airways Flight Attendant Training ........................................................................39 
1.15.5 Evacuation of Passengers and Crewmembers .............................................................40 
1.15.5.1 Occupant Evacuation Exit Usage ...................................................................42 
1.15.5.2 Additional Information About the Flight and Evacuation .............................44 
1.15.6 Emergency Response ...................................................................................................44 
1.16 Tests and Research .................................................................................................................47 
1.16.1 Airplane Performance Study ........................................................................................47 
1.16.1.2 Airbus Simulation ..........................................................................................48 
1.16.2 Biological Material Sampling and Analysis ................................................................48 
1.16.3 Operational Factors and Human Performance Simulations .........................................49 
1.17 Organizational and Management Information .......................................................................51 
1.17.1 Operational Guidance ..................................................................................................51 
1.17.1.1 Abnormal and Emergency Situations ............................................................51 
1.17.1.2 US Airways Engine Dual Failure Checklist ..................................................52 
1.17.1.2.1 Part 1 of the Engine Dual Failure Checklist ........................................ 53 
1.17.1.2.2 Parts 2 and 3 of the Engine Dual Failure Checklist ............................. 56 
1.17.2 Evacuation Procedures .................................................................................................57 
1.17.3 Flight Crew Training ...................................................................................................57 
1.17.3.1 Dual-Engine Failure Training ........................................................................59 
1.17.3.2 Ditching Training ...........................................................................................60 
1.17.3.3 CRM and TEM Training ................................................................................61 
1.17.4 FAA Oversight .............................................................................................................62 
1.18 Additional Information ..........................................................................................................62 
1.18.1 Wildlife-Strike Hazard Information ............................................................................62 
1.18.1.1 General ...........................................................................................................62 
1.18.1.2 Canada Goose Information ............................................................................63 
1.18.1.3 Wildlife-Strike Reporting ..............................................................................64 
1.18.1.4 Wildlife-Strike Hazards in the New York City Metropolitan Area ...............66 
1.18.1.5 Wildlife Hazard Mitigation Research Programs ............................................67 
1.18.2 Previously Issued Safety Recommendation Resulting From This Accident ...............67 
1.18.3 Previous Related Safety Recommendations ................................................................68 
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NTSB Aircraft Accident Report
1.18.3.1 Bird-Strike Hazard Mitigation .......................................................................68 
1.18.3.2 Survivability Issues ........................................................................................70 
1.18.4 Water Swell Testing ....................................................................................................75 
1.18.5 NASA Research on the Challenges of Abnormal and Emergency Situations .............76 
1.18.6 Cold-Water Immersion Information ............................................................................76 
2. Analysis .....................................................................................................................................78 
2.1 General .....................................................................................................................................78 
2.2 Engine Analysis .......................................................................................................................80 
2.2.1 General ...........................................................................................................................80 
2.2.2 Identification of Ingested Birds .....................................................................................80 
2.2.3 Engine Damage ..............................................................................................................80 
2.2.3.1 Engine Spinner, Fan Blade, and Fan Inlet Case Damage ................................81 
2.2.3.2 Engine Core Damage .......................................................................................81 
2.2.4 In-Flight Engine Problem Diagnostics ..........................................................................82 
2.2.5 CFM 56-5B4/P Bird-Ingestion Certification Tests ........................................................83 
2.2.6 Bird-Ingestion Protection Devices for Engines .............................................................85 
2.3 Flight Crew Performance .........................................................................................................87 
2.3.1 Decision to Use Engine Dual Failure Checklist ............................................................87 
2.3.2 Decision to Ditch on the Hudson River .........................................................................88 
2.3.3 Descent and Ditching Airspeed .....................................................................................89 
2.3.4 Decision to Use Flaps 2 for Ditching ............................................................................90 
2.3.5 CRM and TEM During the Accident Sequence ............................................................91 
2.4 Abnormal and Emergency Events Checklist Design ...............................................................91 
2.5 Pilot Training ...........................................................................................................................93 
2.5.1 Dual-Engine Failure Training ........................................................................................93 
2.5.2 Ditching Training ...........................................................................................................94 
2.6 Operational Difficulties Not Factored Into Certification Tests ...............................................95 
2.7 High-AOA-Related Issues .......................................................................................................96 
2.7.1 High-AOA and Low-Airspeed Awareness ....................................................................96 
2.7.2 High-AOA Envelope Limitations ..................................................................................97 
2.8 Bird- and Other Wildlife-Strike Issues ....................................................................................98 
2.8.1 Accident Bird-Strike Event ............................................................................................98 
2.8.2 Wildlife Hazard Mitigation at Part 139-Certificated Airports .......................................99 
2.8.3 FAA Avian Radar Research ........................................................................................100 
2.8.4 Likelihood of a Similar Bird Strike .............................................................................101 
2.8.5 USDA Research and Other Activities .........................................................................102 
2.9 Emergency Response .............................................................................................................103 
2.10 Survival Factors Issues ........................................................................................................103 
2.10.1 Accident-Related Injuries ..........................................................................................103 
2.10.1.1 FR65 Vertical Beam ....................................................................................103 
2.10.1.2 Brace Positions.............................................................................................104 
2.10.2 Evacuation .................................................................................................................105 
2.10.3 EOW and Ditching-Related Equipment ....................................................................107 
2.10.3.1 Slide/Rafts ....................................................................................................107 
2.10.3.1.1 Availability After a Ditching ............................................................. 107 
2.10.3.1.2 Immersion Protection ......................................................................... 108 
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NTSB Aircraft Accident Report
2.10.3.2 Life Lines .....................................................................................................110 
2.10.3.3 Life Vests and Flotation Seat Cushions .......................................................111 
2.10.3.3.1 Equipage ............................................................................................ 111 
2.10.3.3.2 Briefings ............................................................................................. 112 
2.10.3.3.3 Stowage and Retrieval ....................................................................... 113 
2.10.3.3.4 Donning.............................................................................................. 115 
2.10.4 Passenger Education ..................................................................................................117 
2.10.5 Summary ....................................................................................................................118 
3. Conclusions .............................................................................................................................119 
3.1 Findings..................................................................................................................................119 
3.2 Probable Cause.......................................................................................................................123 
4. Safety Recommendations ......................................................................................................124 
4.1 New Recommendations .........................................................................................................124 
4.2 Previously Issued Safety Recommendation Resulting From This Accident .........................128 
Board Member Statement .........................................................................................................129 
5. Appendixes .............................................................................................................................131 
Appendix A: Investigation and Public Hearing .....................................................................131 
Appendix B: Cockpit Voice Recorder Transcript ..................................................................132 
Appendix C: US Airways Engine Dual Failure Checklist .....................................................186 
Appendix D: Bureau d’Enquetes et d’Analyses’ Comments .................................................189 
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NTSB Aircraft Accident Report
Figures
Figure 1. Flight track of the airplane. ............................................................................................. 4 
Figure 2. A photograph showing the airplane occupants on the wings and in the slide/rafts after
the evacuation. ............................................................................................................... 5 
Figure 3. The A320 airspeed scale, including select characteristics and protection speeds. ....... 11 
Figure 4. Cutaway of a turbofan engine showing the LPC, HPC, combustor, HPT, and LPT. ... 15 
Figure 5. A diagram showing the two airflow paths through the turbofan engine. ..................... 16 
Figure 6. Diagram showing the A320 fuselage frame locations. ................................................. 32 
Figure 7. Passenger brace position shown in AC 121-24C. ......................................................... 40 
Figure 8. Passenger brace positions shown in the US Airways safety information card. ............ 40 
Figure 9. Occupant evacuation exit usage. .................................................................................. 43 
Figure 10. Graph depicting the Canada goose population from 1970 to 2008. ........................... 64 

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NTSB Aircraft Accident Report
Tables
Table 1. Injury chart. .......................................................................................................................6 
Table 2. Certification and accident flight values. ..........................................................................23 
Table 3. Summary of emergency response information. ..............................................................46 

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