July 26, 2013
Southwest Airlines Flight 345’s nose gear collapse came after a rapid change in pitch attitude that apparently caused the nose gear to touch down first as it landed at LaGuardia Airport (LGA) July 22, preliminary information released by NTSB says.
The Boeing 737-700, concluding a flight from Nashville International Airport, touched down on LGA’s Runway 4 at 133 kt. with a pitch attitude of “approximately” 3 deg. nose down, NTSB reports. Four sec. prior to touchdown, the plane was at an altitude of 32 ft. traveling 134 kt. with a 2 deg. nose-up attitude.
“Evidence from video and other sources is consistent with the nose-gear making contact with the runway before the main landing gear,” NTSB reports in a July 25 update.
The board has not shed light on where the 737 was in relation to the runway threshold when its nose pitched down, or where along the 7,001-ft. runway the plane touched down.
NTSB’s July 23 update on the accident says the plane slid about 2,175 ft. Images of the accident scene indicate the aircraft came to rest at the entrance of Taxiway Q, which is about 3,700 ft. down Runway 4.
The board says the plane’s flight data recorder captured 1,000 parameters and contained about 27 hr. of data, including the entire flight from Nashville to New York. Investigators planned to transcribe the “relevant” part of the plane’s cockpit voice recorder on July 26.
The 737’s nose gear collapsed “rearward and upward” on touchdown, damaging the electronics bay. The plane slid for 19 sec. before coming to rest.
The aircraft’s slides deployed “normally,” and all 145 passengers and five crewmembers evacuated safely, NTSB says. Nine were treated for “minor” injuries, the board says.