Description

On 15 January 2009, 3000 feet agl after a daytime take-off in VMC from LaGuardia Airport, NY, an Airbus A320-200 experienced an almost complete loss of thrust after encountering a flock of Canada Geese and ingesting birds in both engines. It was subsequently ditched in the Hudson River about 8.5 miles from airport. The ditching was completed successfully. Of the 150 occupants, one member of cabin crew and four passengers were seriously injured and the aircraft was substantially damaged, although later recovered for investigation purposes.

Investigation

An Investigation was carried out by the National Transportation Safety Board (USA) (NTSB). It was established that bird avoidance had been impossible. At the time of impact, the First Officer had been PF but approximately 12 seconds afterwards, the Captain had taken control of the aircraft. Five seconds later he had called for the QRH drill for Dual Engine Failure checklist and this had been commenced whilst an emergency was declared and ATC attempted to assist.

The NTSB concluded that “Even though the engines did not experience a total loss of thrust, the Engine Dual Failure checklist was the most applicable checklist contained in the US Airways QRH, which was developed in accordance with the Airbus QRH, to address the accident event because it was the only checklist that contained guidance to follow if an engine restart was not possible and if a forced landing or ditching was anticipated (starting from 3,000 feet)". However, according to post-accident interviews and CVR data, the flight crew had bee unable to complete this Checklist, which had 3 parts and was 3 pages long; although they were able to complete most of part 1, lack of time precluded starting Parts 2 and 3.

It was found that the Engine Dual Failure checklist had been designed on the assumption that such a failure would occur at a high altitude (above 20,000 feet). According to Airbus, this was because the majority of flight time was at high altitude and, therefore, a dual-engine failure would be most likely to occur at altitudes above 20,000 feet. Airbus advised that they had not considered developing a checklist for use at a low altitude, when limited time is available before ground or water impact. Discussions with A320 operators and another manufacturer also indicated that low altitude, dual-engine failure checklists are not readily available in the industry.

The Investigation noted that, despite being unable to complete the full Engine Dual Failure checklist, the fact that the APU was started improved the outcome of the ditching by ensuring that a primary source of electrical power continued to be available to the aircraft and that the A320 flight control system remained in 'Normal Law' with full flight envelope protection including against a stall.

At the time of the bird strike, the aircraft was about 4.5 miles north-northwest of the threshold of runway 22 at LaGuardia and about 9.5 miles east-northeast of the threshold of runway 24 at Teterboro'. During post-accident interviews, both pilots stated that they considered Hudson River as safest landing option given the airspeed, altitude, and position of the aircraft. The Investigation concluded that the Captain’s decision to ditch in the Hudson River rather than attempting to land at an airport provided the highest probability that the accident would be survivable.

As a result of the accident, the FAA engine and propeller directorate, jointly with EASA, initiated a re-evaluation of the existing bird-ingestion certification regulations to determine whether new rulemaking was necessary.

According to data from the FAA National Wildlife Strike Database, the accident was not a typical bird-strike event. Since 1960, 26 large-transport aircraft have been destroyed because of bird strikes worldwide, and 93 percent of these strikes occurred during takeoff or landing at an altitude of about 500 feet agl or less when the airplane was still near an airport. In contrast, the accident airplane struck birds at an altitude of about 2,800 feet agl about 4.3 miles from LaGuardia, a much higher altitude and further away from an airport than most strikes occur.

According to the wildlife-strike data, the fewest bird strikes in the United States are reported in the winter months, including January, and, in the New York City area, January is one of three months with the historically lowest number of strikes involving Canada geese. Strike data for all wildlife species indicate that the second fewest bird strikes are reported in January. Therefore, the accident event occurred in a month not typically associated with high bird-strike probability.

Probable Cause

"The National Transportation Safety Board determined that the probable cause of this accident was the ingestion of large birds into each engine, which resulted in an almost total loss of thrust in both engines and the subsequent ditching on the Hudson River. Contributing to the fuselage damage and resulting unavailability of the aft slide/rafts were (1) the Federal Aviation Administration’s approval of ditching certification without determining whether pilots could attain the ditching parameters without engine thrust, (2) the lack of industry flight crew training and guidance on ditching techniques, and (3) the captain’s resulting difficulty maintaining his intended airspeed on final approach due to the task saturation resulting from the emergency situation."

"Contributing to the survivability of the accident was (1) the decision-making of the flight crewmembers and their crew resource management during the accident sequence; (2) the fortuitous use of an airplane that was equipped for an extended overwater flight, including the availability of the forward slide/rafts, even though it was not required to be so equipped; (3) the performance of the cabin crewmembers while expediting the evacuation of the airplane; and (4) the proximity of the emergency responders to the accident site and their immediate and appropriate response to the accident."

Safety Recommendations

National Transportation Safety Board made a total of 35 Safety Recommendations as a result of the Investigation. One was made on 7 October 2009 whilst the Investigation was in progress:

• that the Federal Aviation Administration modify [FAA] radar data processing systems so that air traffic controllers can instruct the systems to process the discrete transponder code of an aircraft experiencing an emergency as if it were an emergency transponder code.

(A-09-112)

Thirty four others were made at the conclusion of the Investigation as follows:

• that the Federal Aviation Administration work with the military, manufacturers, and National Aeronautics Space Administration to complete the development of a technology capable of informing pilots about the continuing operational status of an engine.

(A-10-62)

• that the Federal Aviation Administration, once the development of the engine technology has been completed, as asked for in Safety Recommendation A-10-62, require the implementation of the technology on transport-category airplane engines equipped with full-authority digital engine controls.

(A-10-63)

• that the Federal Aviation Administration modify the 14 Code of Federal Regulations 33.76(c) small and medium flocking bird certification test standard to require that the test be conducted using the lowest expected fan speed, instead of 100-percent fan speed, for the minimum climb rate.

(A-10-64)

• that the Federal Aviation Administration, during the bird-ingestion rulemaking database (BRDB) working group’s reevaluation of the current engine bird-ingestion certification regulations, specifically reevaluate the 14 Code of Federal Regulations (CFR) 33.76(d) large flocking bird certification test standards to determine whether they should 1) apply to engines with an inlet area of less than 3,875 square inches and 2) include a requirement for engine core ingestion. If the BRDB working group’s reevaluation determines that such requirements are needed, incorporate them into 14 CFR 33.76(d) and require that newly certificated engines be designed and tested to these requirements.

(A-10-65)

• that the Federal Aviation Administration require manufacturers of turbine-powered aircraft to develop a checklist and procedure for a dual-engine failure occurring at a low altitude.

(A-10-66)

• that the Federal Aviation Administration, once the development of the checklist and procedure for a dual-engine failure occurring at a low altitude has been completed, as asked for in Safety Recommendation A-10-66, require 14 Code of Federal Regulations Part 121, Part 135, and Part 91 Subpart K operators of turbine-powered aircraft to implement the checklist and procedure.

(A-10-67)

• that the Federal Aviation Administration develop and validate comprehensive guidelines for emergency and abnormal checklist design and development. The guidelines should consider the order of critical items in the checklist (for example, starting the auxiliary power unit), the use of opt outs or gates to minimize the risk of flight crewmembers becoming stuck in an inappropriate checklist or portion of a checklist, the length of the checklist, the level of detail in the checklist, the time needed to complete the checklist, and the mental workload of the flight crew.

(A-10-68)

• that the Federal Aviation Administration require 14 Code of Federal Regulations Part 121, Part 135, and Part 91 Subpart K operators to include a dual-engine failure scenario occurring at a low altitude in initial and recurrent ground and simulator training designed to improve pilots’ critical-thinking, task-shedding, decision-making, and workload-management skills.

(A-10-69)

• that the Federal Aviation Administration require 14 Code of Federal Regulations Part 121, Part 135, and Part 91 Subpart K operators to provide training and guidance to pilots that inform them about the visual illusions that can occur when landing on water and that include approach and touchdown techniques to use during a ditching, with and without engine power.

(A-10-70)

• that the Federal Aviation Administration work with the aviation industry to determine whether recommended practices and procedures need to be developed for pilots regarding forced landings without power both on water and land.

(A-10-71)

• that the Federal Aviation Administration require applicants for aircraft certification to demonstrate that their ditching parameters can be attained without engine power by pilots without the use of exceptional skill or strength.

(A-10-72)

• that the Federal Aviation Administration require Airbus operators to amend the ditching portion of the Engine Dual Failure checklist and any other applicable checklists to include a step to select the ground proximity warning system and terrain alerts to OFF during the final descent.

(A-10-73)

• that the Federal Aviation Administration require Airbus operators to expand the angle-of-attack-protection envelope limitations ground-school training to inform pilots about alpha-protection mode features while in normal law that can affect the pitch response of the airplane.

(A-10-74)

• that the Federal Aviation Administration require all 14 Code of Federal Regulations Part 139-certificated airports to conduct wildlife hazard assessments (WHA) to proactively assess the likelihood of wildlife strikes, and if the WHA indicates the need for a Wildlife Hazard Management Plan (WHMP), require the airport to implement a WHMP into its airport certification manual.

(A-10-75)

• that the Federal Aviation Administration work with the U.S. Department of Agriculture to develop and implement innovative technologies that can be installed on aircraft that would reduce the likelihood of a bird strike.

(A-10-76)

• that the Federal Aviation Administration require Airbus to redesign the frame 65 vertical beam on A318, A319, A320, and A321 series airplanes to lessen the likelihood that it will intrude into the cabin during a ditching or gear-up landing and Airbus operators to incorporate these changes on their airplanes.

(A-10-77)

• that the Federal Aviation Administration conduct research to determine the most beneficial passenger brace position in airplanes with nonbreakover seats installed. If the research deems it necessary, issue new guidance material on passenger brace positions.

(A-10-78)

• that the Federal Aviation Administration require, on all new and in-service transport-category airplanes, that cabin safety equipment be stowed in locations that ensure that life rafts and/or slide/rafts remain accessible and that sufficient capacity is available for all occupants after a ditching.

(A-10-79)

• that the Federal Aviation Administration require quick-release girts and handholds on all evacuation slides and ramp/slide combinations.

(A-10-80)

• that the Federal Aviation Administration require 14 Code of Federal Regulations Part 121, Part 135, and Part 91 Subpart K operators to provide information about life lines, if the airplane is equipped with them, to passengers to ensure that the life lines can be quickly and effectively retrieved and used.

(A-10-81)

• that the Federal Aviation Administration require that aircraft operated by 14 Code of Federal Regulations Part 121, Part 135, and Part 91 Subpart K operators be equipped with flotation seat cushions and life vests for each occupant on all flights, regardless of the route.

(A-10-82)

• that the Federal Aviation Administration require 14 Code of Federal Regulations Part 121, Part 135, and Part 91 Subpart K operators to brief passengers on all flotation equipment installed on an airplane, including a full demonstration of correct life vest retrieval and donning procedures, before all flights, regardless of route.

(A-10-83)

• that the Federal Aviation Administration require modifications to life vest stowage compartments or stowage compartment locations to improve the ability of passengers to retrieve life vests for all occupants.

(A-10-84)

• that the Federal Aviation Administration revise the life vest performance standards contained in Technical Standard Order-C13f to ensure that they result in a life vest that passengers can quickly and correctly don.

(A-10-85)

• that the Federal Aviation Administration conduct research on, and require 14 Code of Federal Regulations Part 121, Part 135, and Part 91 Subpart K operators to implement, creative and effective methods of overcoming passengers’ inattention and providing them with safety information.

(A-10-86)

• that the U.S. Department of Agriculture develop and implement, in conjunction with the Federal Aviation Administration, innovative technologies that can be installed on aircraft that would reduce the likelihood of a bird strike.

(A-10-87)

• that the European Aviation Safety Agency modify the small and medium flocking bird certification test standard in Joint Aviation Regulations-Engines to require that the test be conducted using the lowest expected fan speed, instead of 100-percent fan speed, for the minimum climb rate.

(A-10-88)

• that the European Aviation Safety Agency, during the bird-ingestion rulemaking database (BRDB) working group’s reevaluation of the current engine bird-ingestion certification regulations, specifically re-evaluate the Joint Aviation Regulations-Engines (JAR-E) large flocking bird certification test standards to determine whether they should 1) apply to engines with an inlet area of less than 3,875 square inches and 2) include a requirement for engine core ingestion. If the BRDB working group’s reevaluation determines that such requirements are needed, incorporate them into JAR-E and require that newly certificated engines be designed and tested to these requirements.

(A-10-89)

• that the European Aviation Safety Agency require manufacturers of turbine-powered aircraft to develop a checklist and procedure for a dual-engine failure occurring at a low altitude.

(A-10-90)

• that the European Aviation Safety Agency require applicants for aircraft certification to demonstrate that their ditching parameters can be attained without engine power by pilots without the use of exceptional skill or strength.

(A-10-91)

• that the European Aviation Safety Agency require Airbus to redesign the frame 65 vertical beam on A318, A319, A320, and A321 series airplanes to lessen the likelihood that it will intrude into the cabin during a ditching or gear-up landing and Airbus operators to incorporate these changes on their airplanes.

(A-10-92)

• that the European Aviation Safety Agency require, on all new and in-service transport-category airplanes, that cabin safety equipment be stowed in locations that ensure that life rafts and/or slide/rafts remain accessible and that sufficient capacity is available for all occupants after a ditching.

(A-10-93)

• that the European Aviation Safety Agency require quick-release girts and handholds on all evacuation slides and ramp/slide combinations.

(A-10-94)

• that the European Aviation Safety Agency require modifications to life vest stowage compartments or stowage compartment locations to improve the ability of passengers to retrieve life vests for all occupants.

(A-10-95)

Final Report

The Final Report of the Investigation was adopted by the NTSB on 4 May 2010.

Related Articles

• Bird Strike
• Ditching: Rotary Wing Aircraft
• Aircraft Certification for Bird Strike Risk
• Airport Bird Hazard Management
• Operators Checklist for Bird Strike Hazard Management
• Bird Population Trends and Impact on Aviation Safety
• Bird Strike: Guidance for Controllers
• F100, vicinity La Guardia NY USA, 2003: On 4 September 2003, an American Airlines Fokker F100 hit five Canada Geese, just after becoming airborne from La Guardia airport USA, with resultant failure of the No 2 engine and substantial airframe damage. The aircraft carried out an uneventful diversion to New York JFK.