Boeing 737-222 N9044U

Summary

On 19 September 1990 at about 17:00 local time, a Boeing 737-222 registered N9044U, operated by United Airlines, was involved in an incident near Denver, Colorado, United States. 96 people were on board and 2 had minor injuries. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

19 September 1990 at 17:00

Classification

Incident

Location

Denver, Colorado, United States

Nearest airport

Stapleton Intl (DEN)

Coordinates

39.7293, -105.0202

Aircraft

Boeing 737-222

Registration

N9044U

Category

Airplane

Engines

2

Operator

United Airlines

Operating rule

Part 121: Air Carrier

Purpose of flight

Unknown

Phase of flight

Not recorded

Route

Unknown → Wichita

Aircraft damage

Not recorded

Weather

VMC

Light

Day

NTSB number

DEN90IA189

2 people had minor injuries.

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.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB 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.

Quoted verbatim from the NTSB record.