British BAE 146-200 CFBAO

Summary

On 1 May 2000 at about 00:40 local time, a British BAE 146-200 registered CFBAO, operated by Air BC, Ltd., was involved in an incident near Denver, Colorado, United States. 20 people were on board and nobody was injured. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

1 May 2000 at 00:40

Classification

Incident

Location

Denver, Colorado, United States

Coordinates

39.8509, -104.6997

Aircraft

British BAE 146-200

Registration

CFBAO

Category

Airplane

Engines

4

Operator

Air BC, Ltd.

Operating rule

Part 129: Foreign

Phase of flight

Not recorded

Route

Winnipeg → Denver

Aircraft damage

Not recorded

Weather

IMC

Light

Day

NTSB number

DEN00IA080

Nobody was injured.

The accumulation of ice on the supercharger exit guide vanes that reduced core engine airflow, resulting in a loss of power. Factors were the clouds and icing conditions.

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

Read the full NTSB narrative

Power on the no. 1 engine 'rolled back' (dropped to flight idle) while the airplane was in IMC at FL 290. The operator reported considerable convective cloud and thunderstorm activity in the area, with cloud tops reaching FL500. When the flight descended to FL 260, power on nos. 2 and 4 engines also rolled back. As the airplane passed 12,500 feet msl, power returned to the three idling engines. The flight landed without further incident. The airplane was equipped with four unmodified Honeywell ALF502R engines. In certain temperature and moisture conditions, the engines become susceptible to ice accumulation on the supercharger exit guide vanes. This reduces core engine airflow, resulting in a loss of power. Early airworthiness directives prohibited flight in icing conditions above 26,000 feet and at an outside air temperature above -40 degrees C. SAT within 30 nm of thunderstorms. Some operators were granted waivers from these ADs. Recent airworthiness directives mandate certain engine modifications be made by December 2002. Newer models of the airplane feature redesigned engines.

Quoted verbatim from the NTSB record.