Sikorsky S76 N761AF

Summary

On 15 May 2019 at about 23:33 local time, a Sikorsky S76 registered N761AF, operated by Arkansas Childrens Hospital, was involved in an accident near Morrilton, Arkansas, United States. 6 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

15 May 2019 at 23:33

Classification

Accident

Location

Morrilton, Arkansas, United States

Nearest airport

Morrilton Muni (BDQ)

Coordinates

35.1018, -92.7652

Aircraft

Sikorsky S76

Registration

N761AF

Category

Helicopter

Year built

2013

Engines

2

Operator

Arkansas Childrens Hospital

Operating rule

Part 135: Air Taxi & Commuter

Purpose of flight

Business

Phase of flight

Not recorded

Route

Springdale → Little Rock

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CEN19LA146

Nobody was injured.

The improper securing of the exhaust duct bolts, which resulted in the duct becoming unseated and substantial heat damage to the tail rotor drive shaft.

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

Read the full NTSB narrative

The pilot of the helicopter air ambulance flight reported that he experienced fumes in the cockpit while enroute, and shortly thereafter, received visual and aural warnings of smoke in the aft baggage compartment. The pilot initiated an emergency descent into an alternate airport, declared an emergency with air traffic control, and landed uneventfully. Examination of the helicopter revealed that the No. 2 engine exhaust duct was disconnected and unseated, which resulted in engine exhaust entering the compartment containing the tail rotor drive shaft and substantial heat damage to the drive shaft and surrounding areas. Examination of the No. 1 engine exhaust duct revealed that its attach bolts were not tightened to the specified torque value. Additionally, examination of the operator’s other helicopter revealed that the bolts securing both of its two exhaust ducts were not tightened to the specified torque value. The maintenance history of these components was not determined, but given the available information, it is likely that they were improperly secured, which resulted in their loosening and subsequently allowed the exhaust duct to become unseated.

Quoted verbatim from the NTSB record.