United B772 near London on Sep 28th 2025, airframe vibrations

Last Update: September 29, 2025 / 15:33:32 GMT/Zulu time

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Incident Facts

Date of incident
Sep 28, 2025

Classification
Incident

Airline
United

Flight number
UA-939

Departure
London Heathrow, United Kingdom

Destination
San Francisco, United States

Aircraft Registration
N788UA

Aircraft Type
Boeing 777-200

ICAO Type Designator
B772

A United Boeing 777-200, registration N788UA performing flight UA-939 from London Heathrow,EN (UK) to San Francisco,CA (USA) with 271 passengers and 13 crew, was enroute at FL310 over the Lake District near Blackpool,EN (UK) when the crew entered a hold and declared emergency due to unknown airframe vibrations. The crew consulted with dispatch and maintenance trying to clarify whether the vibrations were caused by an engine or something else. The crew subsequently decided to return to London Heathrow, maintained FL310 until normal descent towards London, dumped fuel on the way back and landed safely on Heathrow's runway 27L about 1:50 hours after departure.

A passenger reported the crew shut the left hand engine (PW4090) down due to some problem.

The airline reported a mechanical problem as cause of the return.

The aircraft is still on the ground in London about 22 hours after landing.
Aircraft Registration Data
Registration mark
N788UA
Country of Registration
United States
Date of Registration
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Manufacturer
BOEING
Aircraft Model / Type
777-222
Number of Seats
Hfl Subscribe to unlock
ICAO Aircraft Type
B772
Year of Manufacture
MjqA Subscribe to unlock
Serial Number
Ibqkl Subscribe to unlock
Aircraft Address / Mode S Code (HEX)
Bd mki Subscribe to unlock
Engine Count
N Subscribe to unlock
Engine Manufacturer
Bjdqdcp Subscribe to unlock
Engine Model
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Engine Type
PlbjcdeA Subscribe to unlock
Pounds of Thrust
BAkpg Subscribe to unlock
Main Owner
GclqlcineedhbmminbgqmAl emnkg dmlcjihhelk dmnghgAqejAbcnc qihenAAghAdkjpqipcbpqm gefqbmlkpmhpl qgffmqm Subscribe to unlock
Incident Facts

Date of incident
Sep 28, 2025

Classification
Incident

Airline
United

Flight number
UA-939

Departure
London Heathrow, United Kingdom

Destination
San Francisco, United States

Aircraft Registration
N788UA

Aircraft Type
Boeing 777-200

ICAO Type Designator
B772

This article is published under license from Avherald.com. © of text by Avherald.com.
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