Robinson R44 N7187B

Summary

On 28 June 2013 at about 01:30 local time, a Robinson R44 registered N7187B was involved in an accident near Fielding, Utah, United States. One person was 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

28 June 2013 at 01:30

Classification

Accident

Location

Fielding, Utah, United States

Coordinates

41.8194, -112.0991

Aircraft

Robinson R44

Registration

N7187B

Category

Helicopter

Year built

1998

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Brigham City → Ogden

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR13LA295

Nobody was injured.

The pilot's failure to maintain rotor rpm while traversing a canyon in high-density altitude and gusting wind conditions.

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

Read the full NTSB narrative

The student pilot reported that, upon entering the mouth of a canyon, he slowed the helicopter to between 70 and 75 knots because he had experienced turbulence going through the canyon with his instructor the day before the accident. About halfway through the canyon, the helicopter dropped about 100 feet, and the main rotor rpm was between 80 and 85 percent. He lowered the collective and rolled on the throttle to regain rotor rpm and then turned toward a field to set up for a precautionary landing. During the turn, the main rotor rpm rose to about 90 percent, but, after leveling out, the pilot observed the rpm decrease again to between 80 and 85 percent. The pilot stated that, after he cleared a set of wires and landed the helicopter in the field, the front skid caught on something, and the helicopter tipped over on its left side, which resulted in substantial damage. The calculated density altitude at the time of the accident was 8,830 feet, which could have reduced the available engine torque and, subsequently, the rotor rpm. A postaccident examination of the helicopter's engine and airframe revealed no anomalies that would have precluded normal operation.

Quoted verbatim from the NTSB record.