Compliance With Southwest’s Stabilized Approach Criteria Could Have Prevented Hard Landing at LaGuardia International Airport
JULY 23, 2015
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The
National Transportation Safety Board determined that the captain’s failed
attempt to recover from an unstabilized approach by transferring airplane
control at low altitude instead of performing a go-around, caused a hard
landing at LaGuardia International Airport (LGA) in Queens, New York.
On
July 22, 2013, a Boeing 737, operated as Southwest Airlines flight 345, landed
hard, nose-first, on runway 4 at LGA. Of the 144 passengers and five
crewmembers on board, eight sustained minor injuries and the airplane was
substantially damaged.
Contributing
to the accident was the captain’s failure to comply with standard operating
procedures during the approach.
NTSB found that the first officer was
conducting the approach, and the captain took control away from the first
officer, but not until the plane was 27 feet above the ground.
This late
transfer of control from the first officer to the captain resulted in neither
pilot being able to effectively monitor the airplane’s altitude and pitch
attitude.
According to the Southwest Airlines Flight Operations Manual, the
captain should have called for a go-around well before this point in the
approach instead of trying to salvage the landing.
For
example, Southwest’s stabilized approach criteria require an immediate
go-around if the airplane flaps are not in the final landing configuration by
1,000 feet above the ground. In this case, the flaps were not correctly set
until the airplane was 500 feet above the ground.
To view the full report, including the findings and probable cause,
click: http://go.usa.gov/373SS.
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NTSB Identification: DCA13FA131
Scheduled 14 CFR Part 121: Air Carrier operation of SOUTHWEST AIRLINES CO
Accident
occurred
Monday, July 22, 2013
in
Flushing, NY
Probable Cause Approval Date:
07/22/2015
Aircraft:
BOEING 737 7H4, registration:
N753SW
Injuries: 8 Minor, 141 Uninjured.
NTSB
investigators either traveled in support of this investigation or
conducted a significant amount of investigative work without any travel,
and used data obtained from various sources to prepare this aircraft
accident report.
As the airplane was on final approach, the captain, who was the pilot monitoring (PM), realized that the flaps were not configured as had been briefed, with a setting of 40 degrees for the landing. Data from the flight data recorder (FDR) indicate that the captain set the flaps to 40 degrees as the airplane was descending through about 500 ft altitude, which was about 51 seconds from touchdown. When the airplane was between 100 to 200 ft altitude, it was above the glideslope. Concerned that the airplane was too high, the captain exclaimed repeatedly "get down" to the first officer about 9 seconds from touchdown. About 3 seconds from touchdown when the airplane was about 27 ft altitude, the captain announced "I got it," indicating that she was taking control of the airplane, and the first officer replied, "ok, you got it." According to FDR data, after the captain took control, the control column was relaxed to a neutral position and the throttles were not advanced until about 1 second before touchdown. The airplane touched down at a descent rate of 960 ft per minute and a nose-down pitch attitude of -3.1 degrees, resulting in the nose gear contacting the runway first and a hard landing. The airplane came to a stop on the right side of the runway centerline about 2,500 ft from its initial touchdown. The operator's stabilized approach criteria require an immediate go-around if the airplane flaps or landing gear were not in the final landing configuration by 1,000 ft above the touchdown zone; in this case, the flaps were not correctly configured until the airplane was passing through 500 ft. Further, the airplane's deviation about the glideslope at 100 to 200 ft would have been another opportunity for the captain, as the PM at this point during the flight, to call for a go-around, as indicated in the Southwest Airlines Flight Operations Manual (FOM). Accident data suggest that pilots often fail to perform a go-around or missed approach when stabilized approach criteria are not met. A review of NTSB-investigated accidents by human factors researchers found that about 75% of accidents were the result of plan continuation errors in which the crew continued an approach despite cues that suggested it should not be continued. Additionally, line operations safety audit data presented at the International Air Safety Summit in 2011 suggested that 97% of unstabilized approaches were continued to landing even though doing so was in violation of companies' standard operating procedures (SOPs). The Southwest FOM also states that the captain can take control of the airplane for safety reasons; however, the captain's decision to take control of the airplane at 27 ft above the ground did not allow her adequate time to correct the airplane's deteriorating energy state and prevent the nose landing gear from striking the runway. The late transfer of control resulted in neither pilot being able to effectively monitor the airplane's altitude and attitude. The first officer reported that, after the captain took control of the airplane, he scanned the altimeter and airspeed to gain situational awareness but that he became distracted by the runway "rushing" up to them and "there was no time to say anything." The captain should have called for a go-around when it was apparent that the approach was unstabilized well before the point that she attempted to salvage the landing by taking control of the airplane at a very low altitude. In addition, the captain did not follow SOPs at several points during the flight. As PM, she should have made the standard callout per the Southwest FOM when the airplane was above glideslope, stating "glideslope" and adding a descriptive word or words to the callout (for example, "one dot high"). Rather than make this callout, however, the captain repeatedly said "get down" to the first officer before stating "I got it." The way she handled the transfer of airplane control was also contrary to the FOM, which indicates that the PM should say "I have the aircraft." The flight crew's performance was indicative of poor crew resource management. The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
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