Bell UH-1B N2252A

Summary

On 15 April 1985 at about 14:30 local time, a Bell UH-1B registered N2252A was involved in an accident near Boutte, Louisiana, United States. One person was on board and one was seriously injured. The aircraft was destroyed. No probable cause statement is available for this record.

Date

15 April 1985 at 14:30

Classification

Accident

Location

Boutte, Louisiana, United States

Coordinates

29.8893, -90.3908

Aircraft

Bell UH-1B

Registration

N2252A

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 133: Rotorcraft Ext. Load

Purpose of flight

Other Work Use

Phase of flight

Not recorded

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

FTW85FA188

1 person was seriously injured.

The NTSB has not published a probable cause for this record. No probable cause statement is present in the source data.

Nothing about the cause is stated here that is not in the source record.

Read the full NTSB narrative

THE PLT HAD STABILIZED ACFT IN A 125' HOVER, PRIOR TO PICKING UP A LOAD, WHEN THE ENG SPOOLED DOWN AND ACFT ENTERED TALLTREES WITH LOW ROTOR RPM AND PITCHED NOSE DOWN AS IT DESCENDED THRU THE TREES. GROUND WITNESSES HEARD 2 LOUD 'BANGS' PRIOR TO THE ACFT ENTERING THE TREES. INVESTIGATION OF THE ENG REVEALED THAT THE FUEL CONTROL AND PWR GOVERNOR SCHEDULES WERE SET ABOVE THE SPECIFIED LIMITS. THESE SETTINGS WOULD INCREASE FUEL FLOW AND ENG PWR AVAILABLE WHILE DECREASING OPERATING TEMPERATURES; HOWEVER, IT ALSO REDUCES THE ENG SURGE MARGIN AND INCREASES THE POSSIBILITY OF ENG SURGE (COMRESSOR STALL) AND PWR DROP. IN ADDITION, THE COMPRESSION WAS FOUND DIRTY AND THE BLEED AIR LINE WAS LOOSE, WHICH WOULD HAVE FURTHER REDUCED THE SURGE MARGIN. THE NATURE OF THE LONG LINE OPERATION AND THE SURROUNDING TALL TREES PRECLUDED THE SUCCESSFUL COMPLETION OF THE ENG OUT EMERGENCY PROCEDURE.

Quoted verbatim from the NTSB record.