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US Airways Flight 1250

22 Mar 2008 · Richmond, VA, United States

Boeing 757-200 · Incident: aircraft structural failure en route

From Orlando International Airport (MCO) to Philadelphia International Airport (PHL)

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Event

NTSB case
DCA08IA048
Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
Incident
InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
Completed
API-reported fatalities
0 · all aircraft and ground
Ground fatalities
Unknown
OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
Airline
WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
Visual Meteorological Cond

Boeing 757-200

Aircraft type
Boeing 757
Category
Airplane
RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
N921UW
Operator
US Airways
Onboard fatalities
Unknown
Route
From Orlando International Airport (MCO), Orlando, FLTo Philadelphia International Airport (PHL), Philadelphia, PA
Aircraft age
Not recorded
Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
Part 121: Air Carrier
Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
En route · cruise
Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
Aircraft structural failure
DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
Minor

Cause areas

  • Personnel issues › Task performance

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

NTSB materials laboratory examined the wing-side portions of the left wing trailing edge panel clips from the inboard, middle and outboard positions, with fasteners. Analysis indicated that the wing panel clips fractured due to fatigue. The fatigue region of the inboard clip covered the largest area fraction and was smoothest among the three clips, indicating that fatigue initiated first in the inboard clip. No evidence of corrosion or material anomalies was observed at the fatigue origin. The shape of the fatigue crack in this clip is consistent with fatigue crack propagation primarily under out-of-plane (inboard-outboard) bending loads.

Boeing Service Bulletin (SB) 757-57-0027 was issued April 28, 1988, to address fatigue cracking of attach clips at the location of the fracture in the incident airplane clips. Thickness of the middle clip from the incident airplane indicates that the clips were replaced using kit number 012N8546-1 clips. However, the clips were installed on the incorrect side of the vertical stiffener, and the clips were not installed with spacers as required in SB. Installing the clip on the outboard side of the rear spar vertical stiffener instead of the inboard side would be expected to put additional tensile stress on the inboard side of the clip, which is where fatigue initiation was observed. It is likely that this incorrect installed increased stresses on the clips, which would increase the likelihood of failure due to fatigue.

Patterns in the sealant and filled holes on the inboard clip indicate that it was repositioned to a lower position at some time. The middle clip showed sealant filling areas where the white paint was missing, indicating that the middle clip might have been removed and reinstalled at some time as well.

Probable cause

The installed wing panel clips failed due to fatigue, likely caused by the incorrect installation of the fasteners in response to SB 757-57-0027. Contributing to the incorrect installation was the SB's lack of clarity in the instructions and figures on the correct orientation of the clips and spacers.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record DCA08IA048
Event ID
20080509X00640
Case number
DCA08IA048
Dataset
full-current
Source SHA-256
5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (5)
  • Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
  • Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
  • The date is the local date, which is the same as the UTC date the NTSB stores.
  • API snapshot SHA-256: bf0f471879578bb8074e92dd0d9ed5c6b57981aeb805758c271a0a47e3d92bef; retrieved 2026-09-15T09:38:21.461Z.
  • Corrected after a review of the NTSB narrative, which states these values explicitly: departure. Typo in city name; airport code MCO is Orlando International Airport, Orlando, FL.