About 1638 eastern daylight time, on October 19, 1996, a McDonnell Douglas MD-88, N914DL, operated by Delta Air Lines, Inc., as flight 554, struck the approach light structure and the end of the runway deck during the approach to land on runway 13 at the LaGuardia Airport, in Flushing, New York. Flight 554 was being operated under the provisions of 14 CFR Part 121, as a scheduled, domestic passenger flight from Atlanta, Georgia, to Flushing. The flight departed the William B. Hartsfield International Airport at Atlanta, Georgia, about 1441, with two flightcrew members, three flight attendants, and 58 passengers on board. Three passengers reported minor injuries; no injuries were reported by the remaining 60 occupants. The airplane sustained substantial damage to the lower fuselage, wings (including slats and flaps), main landing gear, and both engines. Instrument meteorological conditions prevailed for the approach to runway 13; flight 554 was operating on an instrument flight rules flight plan.
The National Transportation Safety Board determines that the probable cause of this accident was the inability of the captain, because of his use of monovision contact lenses, to overcome his misperception of the airplane's position relative to the runway during the visual portion of the approach. This misperception occurred because of visual illusions produced by the approach over water in limited light conditions, the absence of visible ground features, the rain and fog, and the irregular spacing of the runway lights.
Contributing to the accident was the lack of instantaneous vertical speed information available to the pilot not flying, and the incomplete guidance available to optometrists, aviation medical examiners, and pilots regarding the prescription of unapproved monovision contact lenses for use by pilots.
The safety issues in this report focused on the possible hazards of monovision contact lenses, visual illusions encountered during the approach, non-instantaneous vertical speed information, the weather conditions encountered during the approach, the guidance in air carrier's manuals regarding flightcrew member duties, the stabilized approach criteria in air carrier's manuals, emergency evacuation procedures, special airport criteria and designation, and LaGuardia Airport issues/runway light spacing.
Safety recommendations concerning these issues were addressed to the Federal Aviation Administration and to optometric associations.
As a result of the investigation of this accident, the National Transportation Safety Board makes the following recommendations:
To the Federal Aviation Administration:
Identify Part 139 airports that have irregular runway light spacing, evaluate the potential hazards of such irregular spacing, and determine if standardizing runway light spacing is warranted. (A-97-84)
Require all 14 CFR Part 121 and 135 operators to review and revise their company operations manuals to more clearly delineate flightcrew member (pilot flying/pilot not flying) duties and responsibilities for various phases of flight, and to more clearly define terms that are critical for safety of flight decisionmaking, such as "stabilized approach." (A-97-85)
Revise FAA Form 8500-8, "Application for Airman Medical Certificate," to elicit information regarding contact lens use by the pilot/applicant. (A-97-86)
Require the Civil Aeromedical Institute to publish and disseminate a brochure containing information about vision correction options, to include information about the potential hazards of monovision (MV) contact lens use by pilots while performing flying duties and to emphasize that MV contact lenses are not approved for use while flying. (A-97-87)
Require all 14 CFR Part 121 and 135 operators to notify their pilots and medical personnel of the circumstances of this accident, and to alert them to the hazards of monovision contact lens use by flightcrew members. (A-97-88)
Require all flight standards district office air safety inspectors and accident prevention specialists to inform general aviation pilots of the circumstances of this accident and to alert them to the hazards of monovision contact lens use by pilots while flying. (A-97-89)
Require all 14 CFR Part 121 and 135 air carriers to make their pilots aware (through specific training, placards, or other means) of the type of vertical speed information (instantaneous/non-instantaneous) provided by the vertical speed indicators installed in their airplanes, and to make them aware of the ramifications that type of information could have on their perception of their flight situation. (A-97-90)
Require all 14 CFR Part 121 and 135 operators to convert, where practical, the non-instantaneous vertical speed instrumentation on airplanes that have inertial reference units installed to provide flightcrews with instantaneous vertical speed information. (A-97-91)
Expedite the development and publication of specific criteria and conditions for the classification of special airports; the resultant publication should include specific remarks detailing the reason(s) an airport is determined to be a special airport, and procedures for adding and removing airports from special airport classification. (A-97-92)
Develop criteria for special runways and/or special approaches giving consideration to the circumstances of this accident and any unique characteristics and special conditions at airports (such as those that exist for the approaches to runways 31 and 13 at LaGuardia Airport) and include detailed pilot qualification requirements for designated special runways or approaches. (A-97-93)
Once criteria for designating special airports and special runways and/or special approaches have been developed as recommended in Safety Recommendations A-97-92 and -93, evaluate all airports against that criteria and update special airport publications accordingly. (A-97-94)
Require all 14 CFR Part 121 and 135 operators to review their flight attendant training programs and emphasize the need for flight attendants to aggressively initiate their evacuation procedures when an evacuation order has been given. (A-97-95)
To optometric associations:
Issue a briefing bulletin to member optometrists, informing them of the potential hazards of and prohibition against monovision (MV) contact lens use by pilots while performing flying duties, and urging them to advise pilot-rated patients of those potential hazards (MV contact lens' effect on distance judgments/perceptions). (A-97-96)