Investigation brief · generated 2026-10-09 · source: NTSB public docket and accident database
BOEING 737-924ER — Las Vegas, NV, USA, 2025-07-02
NTSB number
DCA25LA251
Operator
UNITED AIRLINES INC
Registration
N66831
Highest injury
No injury
Regulation
Part 121
Damage
Substantial
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
United Airlines flight 2136 sustained a tail strike while landing at Harry Reid International Airport (LAS), Las Vegas, Nevada. The flight was a regularly scheduled domestic passenger flight from Washington Dulles Airport (IAD), Dulles, Virginia to LAS. The airplane sustained substantial damage to the underside of the fuselage near the tail.
According to the flight crew, the first officer (FO) was the pilot flying, and the captain was the pilot monitoring when they were cleared to land on runway 26L at LAS. The FO elected to disengage the autopilot and autothrottle at approximately 1,600 feet above ground level (AGL). According to the flightcrew, the airplane was in the landing configuration and during the descent, stabilized approach criteria was met at 1,500 ft., 1,000 ft. and 500 ft. AGL, and the airspeed was close to the correct approach speed.
The captain stated he heard the aircraft aural callouts below 50 feet, and upon hearing “20” he felt no column movement indicative of the start of a flare maneuver, and he stated “flare”, and he felt the column begin to move, quickly followed by the “10” callout.
Data from the digital flight data recorder (DFDR) showed that about 4 seconds prior to the first touchdown, the control column began to move in the airplane nose up direction, increasing the pitch to 7 degrees as the main gear weight on wheels indicator transitioned to “ground”. The column was pushed forward several degrees as the air/ground indicator returned to “air” and the pitch angle reduced to 3.7 degrees. The column was then moved aft in the airplane nose up direction as the weight on wheels transitioned to “ground” again, and the airplane attained a maximum pitch angle of 8.2 degrees and experienced 2.4g vertical acceleration during the second transition of weight on wheel indicator to “ground”. Both pilots reported feeling a second touchdown. The captain then took control of the aircraft for the exit from the runway. The airplane exited the runway and taxied uneventfully to the gate.
Post flight inspection revealed damage to the airplane tail skid assembly and substantial damage to lower fuselage primary structure in the aft portion of the aircraft, requiring replacement of several principal structural elements.
The first officer’s failure to maintain proper pitch attitude during flare which resulted in a bounced landing and a tailstrike.
Verbatim, NTSB determination.
Flight data recorder
Boeing 737-924ER · N66831 — 376,798 samples, 45 parameters, 00:01:00.0 to 00:28:29.0.
Parameter
Max
at
Min
at
Final
at
Pressure altitude ft
29,991.0
00:01:51.3
2,052.0
00:22:00.1
2,116.0
00:28:28.8
Computed airspeed kts
327.8
00:08:22.3
45.0
00:22:20.3
45.0
00:28:28.8
Vertical acceleration g
2.4
00:21:55.4
0.6
00:08:04.7
1.0
00:28:28.9
Engine 1 N1 %RPM
90.8
00:01:42.2
22.9
00:27:49.2
29.0
00:28:28.2
Engine 2 N1 %RPM
90.8
00:01:42.7
2.2
00:28:26.7
2.2
00:28:28.7
Computed from the docket's tabular attachment; times as recorded (local or SRN as published).
Sequence of events (FDR factual report)
Time
Event
Page
00:21:52.3 PDT
Left and right main landing gear weight on wheels transitioned from air to ground
5
00:21:52.3 to 00:21:55.5 PDT
Left and right main landing gear weight on wheels transitioned from air to ground, to air, back to ground, and remained ground for the rest of the data; computed airspeed decreased from about 146 kts to about 141 kts and ground speed decreased from about 157 kts to 153 kts
5
00:21:55.4 PDT
Maximum vertical acceleration recorded at 2.40 g
5
00:21:55.5 PDT
Maximum pitch angle recorded at 8.26 degrees
5
00:21:59.5 PDT
Nose landing gear weight on wheels transitioned from air to ground; computed airspeed decreased to about 126 kts and ground speed decreased to about 136 kts
5
00:22:22 PDT
Aircraft began a right turn and began taxiing
5
00:28:29 PDT
Data ended while the ground speed was 3 kts
5
Extracted by claude-sonnet-5; 7 of 7 stated events verified against the raw recorder data.