De Havilland DHC-8-102 N923HA

Summary

On 12 January 1992 at about 19:18 local time, a De Havilland DHC-8-102 registered N923HA, operated by Usair Express, was involved in an incident near Baltimore, Maryland, United States. 33 people were on board and nobody was injured. The aircraft was slightly damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

12 January 1992 at 19:18

Classification

Incident

Location

Baltimore, Maryland, United States

Nearest airport

Baltimore-Washington Intl (BWI)

Coordinates

39.1703, -76.6707

Aircraft

De Havilland DHC-8-102

Registration

N923HA

Category

Airplane

Engines

2

Operator

Usair Express

Operating rule

Part 121: Air Carrier

Purpose of flight

Unknown

Phase of flight

Not recorded

Route

Unknown → Charlottesville

Aircraft damage

Minor

Weather

VMC

Light

Day

NTSB number

BFO92IA017

Nobody was injured.

IMPROPER INSTALLATION OF THE LOW FUEL PRESSURE WARNING SWITCH SNUBBER ON THE #1 ENGINE, RESULTING IN FATIGUE FAILURE OF THE SNUBBER, A FUEL LEAK (SPRAY), AND SUBSEQUENT EXPLOSION/FIRE DAMAGE. A FACTOR RELATED TO THE INCIDENT WAS: INADEQUATE DESIGN OF THE FIREWALL, WHICH ALLOWED FUEL VAPORS TO MIGRATE TO THE HOT SECTION OF THE ENGINE.

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

Read the full NTSB narrative

AS THE GEAR & FLAPS WERE RETRACTED AFTER TAKEOFF, THE #1 ENGINE LOW FUEL PRESSURE WARNING LIGHT ILLUMINATED. AT ABOUT 400' AGL, A "LOUD BANG" WAS HEARD FOLLOWED BY A #1 ENGINE FIRE WARNING INDICATION. THE ENGINE WAS SHUT DOWN & BOTH FIRE EXTINGUISHING BOTTLES WERE DISCHARGED. THE FLIGHTCREW EXTENDED THE LANDING GEAR BY USING THE ALTERNATE SYSTEM & MADE A NO-FLAP EMERGENCY LANDING. THEY USED EMERGENCY BRAKES, BUT DIRECTIONAL CONTROL WAS LOST & THE AIRCRAFT EXITED THE SIDE OF THE RUNWAY & STOPPED WITH THE FIRE EXTINGUISHED. AN EXAM OF THE #1 ENGINE AREA REVEALED A FAILED LOW FUEL PRESSURE WARNING SWITCH SNUBBER & FIRE DAMAGE TO THE ENGINE, NACELLE & WHEELWELL. THERE WAS EVIDENCE THAT DURING INSTALLATION, THE LOW FUEL PRESSURE WARNING SWITCH SNUBBER WAS TORSIONALLY DEFORMED, THEN FATIGUE & SUBSEQUENT FAILURE OCCURRED. GAPS IN THE FIREWALL ALLOWED LEAKING FUEL (SPRAY) TO ENTER THE HOT SECTION & IGNITE. THIS RESULTED IN AN EXPLOSION & FIRE. FIRE PROPAGATION RESULTED IN BURNED WIRES TO THE #1 STANDBY HYDRAULIC PUMP & A RUPTERED #2 SYSTEM HYDRAULIC LINE.

Quoted verbatim from the NTSB record.