Aviation Accident Summaries

Aviation Accident Summary LAX01IA109

Phoenix, AZ, USA

Aircraft #1

N335SW

Boeing 737-3H4

Analysis

The flight was cleared for the approach to runway 7 and the Captain briefed the First Officer for the approach. After getting their gate assignment, the crew requested, and was cleared for, the approach to runway 8. No briefing was conducted for the approach to runway 8, nor was there any discussion about runway length or that runway 8 was a visual runway and would not have lighting and markings associated with an instrument runway. The target airspeed was 135 knots, and the last airspeed callout was 137 knots. The flight data recorder indicated that the approach speed was 137.5 knots. According to information on the Flight Data Recorder, the airplane touched down approximately 2,000 feet past the approach end of the 6,000 foot long runway. Upon landing, the captain deployed the thrust reversers and applied the wheel brakes. When he noticing the end of the runway approaching faster than anticipated, he applied maximum braking and reverse thrust. The aircraft rolled beyond the end of the pavement and came to rest within one airplane length of the departure end of the runway with the empennage over the end of the runway.

Factual Information

On March 4, 2001, at 2030 hours mountain standard time, a Boeing 737-3H4, N335SW, continued off the end of runway 8 during landing roll and came to a stop in a runway construction area at Phoenix Sky Harbor International Airport, Arizona. The aircraft, operated by Southwest Airlines Company as Flight 2021, departed Los Angeles, California, at 1833 Pacific standard time, and was a regularly scheduled domestic passenger flight operated under 14 CFR Part 121. The aircraft received minor damage. There were no injuries to the airline transport certificated pilot, the First Officer, 3 cabin flight attendants or 114 passengers. The flight was operating on an instrument flight rules flight plan; however, visual meteorological conditions prevailed. According to the cockpit voice recorder transcript of the incident flight, at 2000:34, the crew received the Automatic Terminal Information Service (ATIS) information DELTA, which contained, in part, the following: "runway eight last six thousand feet closed. If unable runway eight, advise Phoenix approach on initial contact. runway seven right localizer/DME out of service. wind zero five zero at four. expect visual approach runway seven right or visual approach eight." At 2015:06, the Captain briefed for a visual approach to runway seven right with an "ILS backup." At 2016:08, the crew learned that they would be parking at gate B-17. At 2016:20, following a discussion with the First Officer concerning the proximity of that gate with various runways, the Captain said, "I guess we want uh, eight if we can get it, huh?" The First Officer responded, "yeah, yeah." At 2018:29, Phoenix Approach Control advised the crew to "join the Phoenix runway seven right localizer. At 2018:46, asked approach, "would the north be available by any chance?" Phoenix Approach responded, "I'll put your request down." At 2022:25, Approach advised the crew to "report runway eight in sight." The First Officer responded, "uh, didn't quite understand that, we are requesting runway eight." Approach responded, "report it in sight." There was no briefing for the approach to runway eight. At 2023:01, flight 2021 was cleared for the visual approach to runway eight. Shortly thereafter, the crew began the before-landing checklist, and at 2027:56, the First Officer noted that the checklist was complete. At 2028:03, the flight was cleared to land on runway eight and the tower controller advised that the wind was, "two five zero at four." The target airspeed was 135 knots, and the last airspeed callout, on final approach, was 137 knots. Runway 8 at Phoenix Sky Harbor is 11,000 feet long and 150 feet wide; however, runway enhancement construction was in progress on the eastern 6,000 feet of the runway. Six thousand feet were removed during construction, and 1,000 feet were added to the non-construction section, leaving 6,000 feet available for landing. At 2056, the Phoenix surface wind was from 230 degrees at 4 knots. According to an inspector from the Federal Aviation Administration Arizona Flight Standards District Office, the aircraft came to a stop approximately 75 feet off the usable landing surface. During construction, runway 8 is a visual runway with a Precision Approach Path Indicator (PAPI) visual glidepath guidance system, but without electronic approach path guidance. A Notice to Airmen (NOTAM) was in effect regarding the runway condition. After stopping in the construction area, the passengers were deplaned via stairs. The Deputy Aviation Director of the Sky Harbor Airport, Planning and Development Department said that runway 8 was being used as a "visual" category runway. It was lighted and marked as a visual runway in accordance with FAA Advisory Circular AC 150/5340-24. This phase of the construction (west portion of the runway in use) had been in progress since February 18, 2001, and there have been "thousands" of operations on the runway without complaint from operators; although, there has been a "significant" refusal rate among pilots offered the runway. The instrument approach lighting system was not being operated. There were runway end identifier lights (REIL) and a PAPI in operation serving each end of the runway. There are high intensity runway edge lights (HIRL); however, the last 2,000 feet of lighting is not colored amber because this is a visual runway and the amber light requirement in the FAA AC pertains to instrument runways. At the time of the incident there were four runway threshold lights on each side of the runway. The outer-most light was aligned with the runway edge lights and the other three lights spaced inward, toward the center of the runway on 10-foot centers. After the incident, the runway marking and lighting were examined by the FAA and found to be incompliance with applicable ACs. After the incident the number of threshold lights was increased to eight per side (16 total per end), the lenses were replaced and the wattage of the light bulbs was increased. The threshold lights are on a different dimming circuit from the edge lights but were "always brighter." The PAPI is positioned so as to provide a 50-foot threshold crossing height using a 3-degree glidepath. The morning after the Southwest incident the 4-box PAPI serving runway 8 was checked. The first box was found positioned correctly, the second box was 1 -minute off, the third box was positioned correctly and the fourth box was 4-minutes off. Regarding the pilot's report of glare, the Deputy Aviation Directorsaid that the evening hours construction is more than 1,000 feet beyond the end of the runway and later at night they close the runway entirely before working nearer the operational portion of the runway. The Phoenix Chief Pilot for Southwest Airlines said that the west end of runway 8/26 was completed first and the east end was being completed at the time of the incident. Southwest's agreement with the airport was that there would be 6,000 of usable runway kept open. He thought the PAPI was positioned for a touchdown point about 1,300 feet from the threshold to accommodate Boeing 757 aircraft, the largest aircraft anticipated to use the runway during construction. The Chief Pilot further said that he examined the runway end environment during hours of darkness approximately 24-hours after the incident occurred. He observed that the red lights laterally outboard of the runway end were not visually conspicuous because of their position outside the pilot's primary field of visual interest (the runway directly in front of him), because of relatively low light bulb wattage and also because of the attenuating effects of the red lens. He also noted that construction was on-going through the nighttime hours on the eastern end of the runway between about the 7,000-foot and the 10,000-foot locations. There was substantial glare directed back toward the runway by construction floodlighting that was partially directed to the west toward the portion of the runway that was operational. As a result of these observations, he directed Southwest Airline's concerns to the City of Phoenix Department of Airports and 3 changes were made: 1) The runway end threshold lights were repositioned within the lateral confines of the width of the runway. The lights then numbered 16 and started at the edge of the runway and were positioned inward toward the center at 10-foot intervals leaving 30-feet clear in the center; 2) The intensity of the light bulbs was increased from 125 watts to 175 watts; and 3) Additional direction was given to the runway construction contractor to control the direction of construction floodlights and reduce glare for aircraft operating on the runway.

Probable Cause and Findings

the pilot's misjudgment of distance, which resulted in a runway overrun. A factor in the incident was the failure of the flightcrew to conduct a briefing for the approach to runway eight.

 

Source: NTSB Aviation Accident Database

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