United B739 near Denver on Sep 1st 2025, generator problems

Last Update: September 3, 2025 / 14:01:13 GMT/Zulu time

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Incident Facts

Date of incident
Sep 1, 2025

Classification
Incident

Airline
United

Flight number
UA-2255

Departure
Denver, United States

Destination
Indianapolis, United States

Aircraft Registration
N57439

Aircraft Type
Boeing 737-900

ICAO Type Designator
B739

A United Boeing 737-900, registration N57439 performing flight UA-2255 from Denver,CO to Indianapolis,IN (USA), was enroute at FL350 about 250nm eastnortheast of Denver when the crew decided to return to Denver. On approach to Denver the crew advised they would be able to vacate the runway but requested emergency services to follow them to the gate. The aircraft landed safely on Denver's runway 35L about 80 minutes after departure.

A passenger reported the aircraft had been lining up for departure from runway 25 then the aircraft taxied along the runway, vacated the runway and stopped while the crew was working checklists, the aircraft subsequently returned to the apron. The captain announced that maintenance had found both left and right generators overfilled with oil, maintenance would clear the right generator, so that the flight could go ahead with the APU as second generator. The aircraft departed, about 35 minutes into the flight the crew announced, that the APU had failed and they needed to return to Denver. The aircraft landed without further incident. A replacement aircraft took them to Indianapolis with a delay of nearly 7 hours.

A replacement Boeing 737-9 MAX registration N17550 reached Indianapolis with a delay of 6.5 hours.
Aircraft Registration Data
Registration mark
N57439
Country of Registration
United States
Date of Registration
NApnjb cbihfeqm Subscribe to unlock
Manufacturer
BOEING
Aircraft Model / Type
737-924ER
Number of Seats
Ak Subscribe to unlock
ICAO Aircraft Type
B739
Year of Manufacture
Qefh Subscribe to unlock
Serial Number
JfAiA Subscribe to unlock
Aircraft Address / Mode S Code (HEX)
Mbqnbg Subscribe to unlock
Engine Count
F Subscribe to unlock
Engine Manufacturer
Mklhimpm Subscribe to unlock
Engine Model
KibgAgfAAjng Subscribe to unlock
Engine Type
H chlnnpc Subscribe to unlock
Pounds of Thrust
Ijgfd Subscribe to unlock
Main Owner
BlAbbhjcbdA pihefqq qlleklkqncjbpdfheb qcnbekjidpddnii AcekligilejkepmlgkApqfkkAhAfjnnAnlficbnipnh dkf Subscribe to unlock
Incident Facts

Date of incident
Sep 1, 2025

Classification
Incident

Airline
United

Flight number
UA-2255

Departure
Denver, United States

Destination
Indianapolis, United States

Aircraft Registration
N57439

Aircraft Type
Boeing 737-900

ICAO Type Designator
B739

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