McDonnell Douglas 369E N311VT

Summary

On 4 October 2016 at about 19:10 local time, a McDonnell Douglas 369E registered N311VT, operated by Volcano Helicopters Inc, was involved in an accident near Waimea, Hawaii, United States. 3 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

4 October 2016 at 19:10

Classification

Accident

Location

Waimea, Hawaii, United States

Coordinates

20.1122, -155.6858

Aircraft

McDonnell Douglas 369E

Registration

N311VT

Category

Helicopter

Year built

1987

Engines

1

Operator

Volcano Helicopters Inc

Operating rule

Part 135: Air Taxi & Commuter

Phase of flight

Not recorded

Route

Hilo → Hilo

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR17LA005

Nobody was injured.

Impact of the lift cable after it exited the helicopter during liftoff with the main rotor (MR) blades, which resulted in the separation of an MR blade tip and the vertical vibration of the helicopter.

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

Read the full NTSB narrative

The commercial pilot reported that, after completing an external cargo lift operation, he landed at a remote location to jettison the lift cable and to board the two ground workers for a ferry flight back to their home base. Shortly after liftoff, the pilot felt a moderate aberration in the cyclic flight control, followed by a significant vertical vibration. The pilot subsequently observed that the main rotor (MR) blade track had a substantial blade spread. Subsequently, the pilot conducted a forced emergency landing to a nearby suitable area. A postaccident examination of the helicopter revealed that one MR blade was missing about 9 inches of its blade tip, consistent with impact with an object of substantial mass, possibly a cable; the damage was not consistent with separation of the blade end due to a preexisting condition. Two other MR blades exhibited scuff marks and scratches along their leading edges with areas that had defined parallel scratches, consistent with cable impact. The pilot reported that he released the lift cable before the flight, and it was not recovered. The pilot added that, after he released the cable, the ground crew placed the coiled cable in the rear compartment that had no doors. Examination of the lift cable release mechanism revealed no damage to the component, and additional testing revealed no anomalies that would have precluded normal operation of the lift cable mechanism. There is no evidence that the lift cable remained attached to the hook during the accident flight; therefore, it was likely in the passenger compartment at liftoff as reported by the pilot. Therefore, based on the damage to the MR blades, it is likely that the cable exited the helicopter during liftoff and subsequently impacted the MR, which resulted in the separation of an MR blade tip and the vertical vibration of the helicopter.

Quoted verbatim from the NTSB record.