Investigation brief · generated 2026-10-09 · source: NTSB public docket and accident database
BOEING 737-7H4 — Santa Clarita, CA, USA, 2010-02-13
NTSB number
WPR10LA134
Operator
SOUTHWEST AIRLINES CO
Registration
N221WN
Highest injury
Serious injury
Regulation
Part 121
Damage
—
Cohort
Part 121 airline
Recorder data
Tier 1 — decoded recorder tables
Every sentence below is taken directly from NTSB records — the accident database, the docket's recorder reports and the Board's findings — with its source noted. Nothing is paraphrased or inferred.
NTSB summary
During descent to landing, the flight crew inadvertently turned about 27 degrees off their air traffic controller-assigned heading. When advised by the controller to check the airplane’s heading, the flight crew noted the heading discrepancy and immediately initiated a turn back to the assigned heading. During the turn, the flight crew received a traffic alert and collision avoidance system resolution advisory (RA). The captain responded to the RA by initiating an estimated 1,500- to 2,000-foot-per-minute rate of descent followed by an approximate 2,000-foot-per-minute climb. During the RA response maneuvers, three flight attendants were standing in the aft galley, one of whom was seriously injured.
The pilot’s abrupt airplane pitch change maneuver. Contributing to the accident was the flight crew’s failure to maintain the heading specified by the air traffic controller, which would have avoided the near collision course with an unidentified airplane that triggered the traffic alert and collision avoidance system resolution advisory.
Verbatim, NTSB determination.
Flight data recorder
— 24,840 samples, 41 parameters, 20:44:30.0 to 20:53:29.9.
Parameter
Max
at
Min
at
Final
at
Pressure altitude ft
7,891.0
20:44:31.7
532.0
20:52:45.7
606.0
20:53:29.7
Computed airspeed kts
269.0
20:46:04.7
45.0
20:52:54.7
45.0
20:53:29.7
Vertical acceleration g
2.9
20:45:52.3
0.1
20:45:51.0
1.0
20:53:29.9
Engine 1 N1 %RPM
95.4
20:45:55.4
19.5
20:53:06.4
20.4
20:53:29.4
Engine 2 N1 %RPM
95.2
20:45:54.9
19.4
20:53:06.9
20.2
20:53:29.9
Computed from the docket's tabular attachment; times as recorded (local or SRN as published).
Sequence of events (FDR factual report)
Time
Event
Page
20:45:40 GMT
TCAS Down Advisory set "On" followed by a pitch up then a pitch down motion
3
20:45:49 GMT
TCAS Down Advisory set "Off" and TCAS Up Advisory set "On", accompanied by a pitch up motion
3
20:45:51 GMT
Minimum recorded vertical acceleration of 0.09 g's
3
20:45:52 GMT
Maximum recorded vertical acceleration of 2.93 g's
3
20:46:10 GMT
TCAS Up Advisory set "Off"
3
Extracted by claude-sonnet-5; 5 of 5 stated events verified against the raw recorder data.