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NTSB Report
September 19, 1990 · Boeing 737-222 · N9044U
Denver, CO
Overview
Report Status
Probable Cause
Event Type
Incident
Date
September 19, 1990
Injury Outcomes
2 injuries (2 minor injuries), 94 uninjured
Location
Denver, CO
Aircraft
Boeing 737-222
Tail Number
N9044U
Operator
United Airlines
Injuries
Minor
NTSB Number
DEN90IA189
SHORTLY AFTER PUSHBACK IT WAS NOTICED THAT THE #2 ENG DOOR 2 RIGHT HANDLE WAS NOT FLUSH. THE ENG WAS SHUT DOWN AND GROUND MAINT PERSONNEL CLOSED THE DOOR FROM THE OUTSIDE. THE CABIN THEN BEGAN TO FILL WITH DENSE SMOKE. THE CAPTAIN, USING RADIO AND AN OPEN WINDOW, WAS UNSUCCESSFUL IN GETTING A JETWAY TO THE AIRPLANE, AND THE CREW AND PAX EXITED USING SLIDES. IT WAS LATER DETERMINED THAT THE BATTERY BUSS RELAY (R1) AND BATTERY TRANSFER RELAY (R2) HAD FAILED. THE AIRPLANE HAD BEEN PUSHED BACK AT GATE B-8, AND HAD RECEIVED CLEARANCE TO GATE B-20 FOR THE EVACUATION. THERE WAS NO JETWAY OPERATOR PRESENT, AND GROUND PERSONNEL ARE NOT CROSS-TRAINED TO OPERATE A JETWAY. WHEN THE #2 ENG WAS SHUT DOWN, THE ELECTRICAL TRANSFER SYSTEM PICKED UP THE LOAD. THE FLIGHTCREW DID NOT POWER THE RIGHT BUS FROM THE APU.
NTSB Probable Cause
THE FAILURE OF THE FLIGHT CREW TO FOLLOW EMERGENCY PROCEDURES/DIRECTIVES. FACTORS WERE THE FAILURE OF THE AIRCRAFT ELECTRICAL SYSTEM (RELAYS) AND THE FAILURE OF THE COMPANY TO PROVIDE A JETWAY OPERATOR.
Full Narrative
SHORTLY AFTER PUSHBACK IT WAS NOTICED THAT THE #2 ENG DOOR 2 RIGHT HANDLE WAS NOT FLUSH. THE ENG WAS SHUT DOWN AND GROUND MAINT PERSONNEL CLOSED THE DOOR FROM THE OUTSIDE. THE CABIN THEN BEGAN TO FILL WITH DENSE SMOKE. THE CAPTAIN, USING RADIO AND AN OPEN WINDOW, WAS UNSUCCESSFUL IN GETTING A JETWAY TO THE AIRPLANE, AND THE CREW AND PAX EXITED USING SLIDES. IT WAS LATER DETERMINED THAT THE BATTERY BUSS RELAY (R1) AND BATTERY TRANSFER RELAY (R2) HAD FAILED. THE AIRPLANE HAD BEEN PUSHED BACK AT GATE B-8, AND HAD RECEIVED CLEARANCE TO GATE B-20 FOR THE EVACUATION. THERE WAS NO JETWAY OPERATOR PRESENT, AND GROUND PERSONNEL ARE NOT CROSS-TRAINED TO OPERATE A JETWAY. WHEN THE #2 ENG WAS SHUT DOWN, THE ELECTRICAL TRANSFER SYSTEM PICKED UP THE LOAD. THE FLIGHTCREW DID NOT POWER THE RIGHT BUS FROM THE APU.
Flight
Event TypeIncident
Event Time11:00 MDT
Nearest AirportStapleton Intl (0nm N)
Runway0
Runway Length0
Runway Width0
Flight Plan FiledIFR
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBoeing 737-222
Tail NumberN9044U
Aircraft CategoryAir
OperatorUnited Airlines
Operating RulePart 121
Engines2
Engine TypeTurbojet
Engine DetailsP&W · Turbojet · 14000
Seats113
People & Injuries
Injury Summary2 injuries (2 minor injuries), 94 uninjured
Fatal0
Serious0
Minor2
Uninjured94
Total96
Crew 1Age 51 · First Class
Conditions
ConditionsVMC
LightDaylight
Wind30° @ 5 kt
Visibility7 sm
CeilingNone
Temperature / Dew Point0 C
Altimeter0
Weather SourcePILO