DCA14LA137

NTSB accident investigation · Boeing 757 · San Diego, CA · July 30, 2014

Accident · No injuriesLimited investigationFinal report
Date
July 29, 2014, 22:40 local (Jul 30, 2014, 05:40 UTC)
Place
San Diego, CA
Injuries
174 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N553UABoeing 757
Defining event
Landing-flare/touchdown: Tailstrike
Weather
Visual (VMC) · Night
Status
Completed · report June 8, 2020
Report
Approved by Office Director
NTSB office
Major Investigations Division
Parties
FAA
FAA report
20140729014389A
Case key
89806

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

the first officer's failure to maintain the correct airspeed and pitch attitude during landing that resulted in a tailstrike.

Findings · 1

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Action: incorrect action performancePersonnel issues › Action/decision · PilotBoeing 757-222: 1 caseAll aircraft: 1,386 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

TailstrikeLanding-flare/touchdownBoeing 757-222: 1 caseAll aircraft: 124 casesDefining event

Analysis

On July 29, 2014, about 2240 pacific daylight time, United Airlines flight 345, a Boeing 757-222, N553UA, experienced a tailstrike while landing at the San Diego International Airport (SAN), San Diego, California. There were no injuries to the 174 persons onboard. The airplane sustained substantial damage. The flight was operating under 14 Code of Federal Regulations Part 121 as a regularly scheduled passenger flight from George Bush Intercontinental Airport (IAH), Houston, Texas, to SAN. According to the operator, the first officer (FO) was the pilot flying and the captain was the pilot monitoring. The accident flight was the second flight of the day for both crew members. The climb, cruise, and descent portions of the flight were uneventful. The airplane was configured for a flaps 30 landing with the autopilot off for the visual approach to runway 27. The target airspeed for the landing was 130 knots, 5 knots above VREF. An airplane performance study was completed based on the FDR data from the flight. The study showed the wind was constant during the final descent to the runway with about a 4-knot headwind component. At about 50 feet radio altitude, the FO began to gradually pull back on the column until the elevators deflected 12 degrees airplane nose up at touchdown. Touchdown occurred with a sink rate near 0, a pitch attitude of about 6 degrees and an airspeed of 120 knots (5 knots below VREF). After touchdown, thrust was commanded to idle and the speedbrakes were deployed. The FO then began to gradually release column backpressure; however, pitch attitude continued to increase towards the gear-struts-compressed tail strike pitch attitude. The airplane's pitch attitude eventually exceeded the gear struts compressed tail strike attitude of 10.5 degrees. The FO commanded reverse thrust as the tail strike occurred and then increased to maximum reverse thrust after derotation had occurred. Published Flight Operations Technical Bulletins issued by the manufacturer in 1988 and 1990 instructed pilots to immediately lower the nose after touchdown (i.e. apply forward pressure) and warned pilots that bleeding off airspeed below VREF prior to touchdown will increase body attitude and thereby increase the likelihood of a tail strike. In this accident, touchdown occurred about 5 knots below VREF and the nose-up elevator remained for nearly 3.5 seconds, causing the aft fuselage to contact the runway. Inspection of the airplane revealed substantial abrasion damage to two aft, lower skin panels spanning an area about 4 feet long by 1.5 feet wide. In addition, the forward and aft lower chords on the aft pressure bulkhead (APB) were deformed and the lower APB web was buckled.

Factual narrative

On July 29, 2014, about 2240 pacific daylight time, United Airlines flight 345, a Boeing 757-222, N553UA, experienced a tailstrike while landing at the San Diego International Airport (SAN), San Diego, California. There were no injuries to the 174 persons onboard. The airplane sustained substantial damage. The flight was operating under 14 Code of Federal Regulations Part 121 as a regularly scheduled passenger flight from George Bush Intercontinental Airport (IAH), Houston, Texas, to SAN. According to the operator, the first officer (FO) was the pilot flying and the captain was the pilot monitoring. The accident flight was the second flight of the day for both crew members. The climb, cruise, and descent portions of the flight were uneventful. The airplane was configured for a flaps 30 landing with the autopilot off for the visual approach to runway 27. The target airspeed for the landing was 130 knots, 5 knots above VREF. An airplane performance study was completed based on the FDR data from the flight. The study showed the wind was constant during the final descent to the runway with about a 4-knot headwind component. At about 50 feet radio altitude, the FO began to gradually pull back on the column until the elevators deflected 12 degrees airplane nose up at touchdown. Touchdown occurred with a sink rate near 0, a pitch attitude of about 6 degrees and an airspeed of 120 knots (5 knots below VREF). After touchdown, thrust was commanded to idle and the speedbrakes were deployed. The FO then began to gradually release column backpressure; however, pitch attitude continued to increase towards the gear-struts-compressed tail strike pitch attitude. The airplane's pitch attitude eventually exceeded the gear struts compressed tail strike attitude of 10.5 degrees. The FO commanded reverse thrust as the tail strike occurred and then increased to maximum reverse thrust after derotation had occurred. Published Flight Operations Technical Bulletins issued by the manufacturer in 1988 and 1990 instructed pilots to immediately lower the nose after touchdown (i.e. apply forward pressure) and warned pilots that bleeding off airspeed below VREF prior to touchdown will increase body attitude and thereby increase the likelihood of a tail strike. In this accident, touchdown occurred about 5 knots below VREF and the nose-up elevator remained for nearly 3.5 seconds, causing the aft fuselage to contact the runway. Inspection of the airplane revealed substantial abrasion damage to two aft, lower skin panels spanning an area about 4 feet long by 1.5 feet wide. In addition, the forward and aft lower chords on the aft pressure bulkhead (APB) were deformed and the lower APB web was buckled.

Aircraft

Registration
N553UA
Reported as
Boeing 757 (222)
Category
Airplane
Serial number
25277
Built
1992
Airframe hours
72,854
Engines
P & W PW2040, 18,150 horsepower, turbo fanP & W PW2040, 18,150 horsepower, turbo fan
Damage
Substantial damage
Flight
Part 121
Operator
United Airlines
Registered owner
Wilmington Trust Company Trustee
Airworthiness certificate
Standard, Transport
Last inspection
Continuous airworthiness · May 18, 2014
Departed
IAH · Houston, TX
Destination
SAN · San Diego, CA
Flight plan
IFR
Airport
SAN · San Diego Intl, runway 27, 9,400 × 200 ft, asphalt
Equipment
Electronic multifunction display, Data recorder, Auto-pilot, Angle of attack indicator, Stall warning system, Onboard weather

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
54
Injuries
None
Certificate
Airline transport
Airplane ratings
Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
April 15, 2014
Seat
Left
Restraint
5-point
Flight hours
19,400 total · 7,000 in this make and model · 16,000 as pilot in command
Role
Co-pilot
Age
50
Injuries
None
Certificates
Private, Flight engineer, Airline transport
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
March 4, 2014
Seat
Right
Restraint
5-point
Flight hours
6,000 total · 258 in this make and model · 3,000 as pilot in command

Weather

Conditions
Visual (VMC) · Night
Wind
300° at 6 knots
Visibility
9 statute miles
Lowest ceiling
None
Temperature
73 °F, dew point 66 °F
Altimeter
29.98 inHg

Docket · 4

The files NTSB released with the investigation on July 14, 2020, on NTSB’s docket system: statements, records, photos and specialists’ reports. 25.3 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.