Pilot Debrief

Airbus A320 near Newark, NJ — 2008-01-25

Final reportDCA08IA033
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Date
2008-01-25
Location
Newark, NJ, USA
Airport
EWR
Aircraft
Airbus A320
Registration
N462UA
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Initial climb

Probable cause

a fault in the airplane's AC 1 electrical bus that caused a number of other electrical busses on the aircraft to lose power.

NTSB narrative

This incident occurred when United Airlines flight 731 experienced a fault in the airplane's AC 1 electrical bus, one of the two primary electrical distribution systems for the airplane, which in turn caused a number of other electrical busses on the aircraft to lose power. The loss of this electrical power led to the loss of a number of aircraft displays and systems. During the flights return to the airport, multiple messages on the electronic centralized aircraft monitoring (ECAM) system, which provides information to the crew regarding failures that have occurred on the aircraft along with recommended corrective actions, were being displayed then removed by the ECAM system, making it difficult for the flight crew to interpret and address the error messages. There were no faults found in the airplane wiring and the testing and teardown found don faults in the #1 integrated drive generator (IDG), bus tie contactor (BTC), and generator control unit (GCU).

Analysis

Primary failure mode
Mechanical failure
First missed decision gate
Crew could have performed alternate power configuration sooner.

NTSB coding

  • Electrical system malf/failure · Initial climb

Evidence available

  • FDR / data
  • 4 docket documents
View NTSB final reportView NTSB docket

Docket documents4

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