Rotorway SCORPION 133 N51017

Summary

On 5 July 2024 at about 13:01 local time, a Rotorway SCORPION 133 registered N51017 was involved in an accident near Andale, Kansas, United States. One person was on board and one died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

5 July 2024 at 13:01

Classification

Accident

Location

Andale, Kansas, United States

Coordinates

37.7851, -97.6384

Aircraft

Rotorway SCORPION 133

Registration

N51017

Category

Helicopter

Year built

1988

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Andale → Unknown

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

CEN24FA248

1 person died.

The pilot’s abrupt control inputs, which resulted in a low-G condition, main rotor mast bumping, and subsequent severing of the tailboom by the main rotor blades.

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

Read the full NTSB narrative

The pilot departed from his residence on a local area flight to practice maneuvers in the experimental helicopter. A witness heard a loud “bang” and observed debris separating from the helicopter as it descended to the ground. Surveillance camera audio captured the sound of the helicopter’s experimental engine at a constant high-power setting, followed by a momentary reduction in power. Shortly thereafter, the audio captured multiple impacts and the helicopter came into view inverted, then descended to the ground. A postimpact fire consumed the wreckage. Postaccident examination of the wreckage found that the aft tailboom had separated from the helicopter and was located about 150 yards from the main wreckage. An impact mark consistent with the shape of a main rotor blade was noted at the right side of the tubular structure at the separation area, consistent with a main rotor blade impact. While no mechanical anomalies were found during the airframe and engine examination, the examination was limited due to extensive fire damage. The throttle control cable was found thermally separated from the collective control and the snap-out ball joint was not in the safety position; it was found separated from the carburetor. However, the surveillance audio of the engine’s reduction and increase of rpm before the main rotor’s impact with the tailboom are consistent with an intact throttle control and indicate that the throttle cable likely separated from the carburetor during the impact with terrain. The pilot did not hold a helicopter rating. His last solo endorsement was October 07, 2022, and was valid until January 05, 2023. The accident occurred 18 months after the expiration of the last solo endorsement, and the pilot was not authorized to conduct solo flight operations at the time of the accident. The pilot previously reported that he felt uncomfortable performing autorotations and requested additional training from a flight instructor; however, it was unknown what maneuvers he was performing during the accident flight. Teetering main rotor systems, such as the one on the accident helicopter, are particularly susceptible to main rotor mast bumping during the low-G conditions that result from abrupt forward (nose-down) cyclic inputs. Based on the available evidence the pilot likely applied abrupt control inputs while performing an unknown maneuver, which resulted in main rotor mast bumping during a low-G condition and subsequent main rotor blade contact with and subsequent separation of the tailboom..

Quoted verbatim from the NTSB record.