SEA07LA028

NTSB accident investigation · Robinson R-22 · Bountiful, UT · December 9, 2006

Accident · Minor injuriesLimited investigationFinal report
Date
December 9, 2006, 11:30 local (18:30 UTC)
Place
Bountiful, UT
Injuries
2 minor
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N611SCRobinson R-22
Weather
Visual (VMC) · Day
Status
Completed · report April 25, 2007
Report
Approved by Office Director
Parties
Salt Lake City FSDO
FAA report
20061209025469A
Case key
64986

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

The pilot's improper decision to fly up a mountain canyon at low level without knowledge of the wind conditions. Factors associated with the accident are gusty winds, downdrafts, and rough/uneven terrain.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

In flight encounter with weatherCruise
Weather condition - downdraftFactor
Weather condition - gustsFactor
Low altitude flight/maneuver - performedPilot in commandFactor
Terrain condition - mountainous/hilly
In-flight planning/decision - improperPilot in commandCause
Roll overLanding - flare/touchdown
Terrain condition - rough/unevenFactor
Precautionary landing - performedPilot in command

Analysis

The pilot was taking a passenger on a local sight-seeing flight, and flew up a mountain canyon. As he started up the canyon, he encountered a slight wind gust, but decided to continue up the canyon. Eventually, he encountered gusting variable wind conditions and significant downdrafts. He elected to turn around and fly out of the canyon. As soon as he started to turn, the helicopter encountered a strong downdraft, and it began to sink rapidly. The main rotor rpm began to slow, and the pilot increased power and lowered the collective. Although he was able to fly out of this downdraft, the helicopter entered another strong downdraft, and sank toward terrain with its main rotor rpm decreasing. In order to stop the descent, the pilot raised the collective, but the helicopter continued to sink, and the main rotor rpm again began to decay. By that time, the pilot was very close to the terrain, and decided to land instead of trying to fly further in the presence of the strong downdrafts. Although the pilot was able to successfully touch down in an open area, soon after the skids came in contact with the rough, steeply-sloped terrain, the helicopter rolled onto its side.

Factual narrative

On December 9, 2006, approximately 1130 mountain standard time, a Robinson R-22 helicopter, N611SC, rolled over onto its side during an off-airport precautionary landing about 10 miles east of Bountiful, Utah. The commercial pilot and his passenger received minor injuries, and the aircraft, which is operated by Suncrest Aviation, of Spanish Fork, Utah, sustained substantial damage. The 14 CFR Part 91 personal pleasure flight, which departed Bountiful Skypark about 20 minutes prior to the accident, was being operated in visual meteorological conditions. No flight plan had been filed.

According to the pilot, he was taking his father-in-law on a local sight-seeing flight, and while looking around the local area he flew east up Holbrook Canyon. As he started up the canyon, he encountered a slight wind gust, but he decided to continue on up the canyon. Eventually he encountered gusting variable wind conditions and significant downdrafts. He therefore decided to turn around and fly back out of the canyon. As soon as he started to turn around, the helicopter encountered a strong downdraft, and it began to sink rapidly. As it began to sink, the main rotor rpm began to slow, so the pilot increased power and lowered the collective. Although the pilot was able to fly out of this downdraft, the aircraft entered another strong downdraft, and once again it sank toward the terrain with its main rotor rpm decreasing. In order to stop the descent, the pilot raised the collective, but the helicopter continued to sink and once again the main rotor rpm began to decay. By that time the helicopter was very close to the terrain, and because he felt he had no other choice, when the pilot spotted an open area he decided to land instead of trying to fly further in the presence of the strong downdrafts. Although the pilot was able to successfully touch down in the open area, soon after the skids came in contact with the rough steeply-sloped mountainous terrain, the helicopter rolled over onto its side.

Aircraft

Registration
N611SC
Reported as
Robinson R-22
Category
Helicopter
Serial number
3869
Airframe hours
674
Engine
Lycoming O-360 j2a, 145 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Suncrest Aviation
Registered owner
Fly LLC
Airworthiness certificate
Standard, Normal
Last inspection
AAIP · November 1, 2006 · 20 hours before
Departed
KBTF · Bountiful, UT
Destination
KBTF

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
27
Injuries
Minor
Certificates
Flight instructor, Commercial
Instrument ratings
Helicopter
Medical
Class 2, Without waivers/limitations
Last flight review
May 1, 2006
Seat
Left
Flight hours
330 total · 285 in this make and model · 275 as pilot in command · 125 in the last 90 days · 30 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
Variable at 10 knots, gusting 15
Visibility
10 statute miles
Lowest ceiling
None
Temperature
36 °F

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.