LAX05TA008

NTSB accident investigation · Hughes OH-6A · Jacumba, CA · October 15, 2004

Accident · No injuriesFinal report
Date
October 15, 2004, 01:15 local (08:15 UTC)
Place
Jacumba, CA
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N6639RHughes OH-6A
Weather
Visual (VMC) · Night/dark
Status
Completed · report January 31, 2006
Report
Approved by Office Director
Parties
Federal Aviation Administration
FAA report
20041015028309A
Case key
60363

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 failure to maintain adequate clearance from the mountainous terrain, which resulted in the helicopter's tail rotor blades impacting rocks. A factor in the accident was the pilot's complacency.

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 collision with terrain/waterManeuvering
Light condition - dark night
Terrain condition - mountainous/hilly
Terrain condition - rock(s)/boulder(s)
ComplacencyPilot in commandFactor
Clearance - not maintainedPilot in commandCause
Rotor system,tail rotor blade - blade strike

Analysis

The public-use law enforcement helicopter collided with rocks and terrain while performing low altitude maneuvers in mountainous terrain on a dark night. The pilot maneuvered the helicopter in a turning descent, in an effort to provide the observer with a better view of the area. As he turned the helicopter, he heard a loud bang, followed by a vibration, at which point he opted to land. After egressing the helicopter, he discovered that approximately 3 inches of each tail rotor blade were missing. Days later, while inspecting the accident scene, he also found red and white paint transfers on a rock, located about 100 yards uphill from the landing site; he noted that the tail rotor blades were painted red and white. He thought that his complacency and eagerness to finish the flight might have contributed to him misjudging the maneuver. He reported no mechanical malfunctions of failures with the helicopter prior to impact.

Factual narrative

On October 15, 2004, about 0115 Pacific daylight time, a Hughes OH-6A, N6639R, collided with terrain while performing low altitude maneuvers 4 miles west of the Jacumba Airport, Jacumba, California. The US Border Patrol Air Operations was operating the helicopter under the provisions of 14 CFR Part 91. The commercial pilot and a flight crewmember were not injured; the helicopter sustained substantial damage. The local public-use border patrol flight departed Imperial County Airport, Imperial, California, about 2215 on October 14. Visual meteorological conditions prevailed on the dark night, and a flight plan had not been filed.

In a written statement, the pilot reported that he was assisting border patrol ground units with a group of illegal aliens located about 4 miles west of Jacumba, in mountainous terrain consisting of tall weeds and thick brush. While maneuvering in the area, the other flight crewmember, an observer, indicated to the pilot that she thought she saw movement in some bushes located behind the helicopter. The pilot maneuvered the helicopter in a turning descent in an effort to provide the observer with a better view of the area. Thinking that the helicopter's tail rotor would be clear of terrain, the pilot maneuvered around the brush. As he turned the helicopter, he heard a loud bang, followed by a vibration, at which point he opted to land.

The pilot further stated that after egressing, he completed an inspection of the helicopter. During the examination he discovered that approximately 3 inches of each tail rotor blade were missing; he did not find any other damage. He reported that 3 days after the accident, while inspecting the accident scene, he found red and white paint transfers on a rock, located about 100 yards uphill from the landing site; he noted that the tail rotor blades were painted red and white.

During a telephone conversation with a National Transportation Safety Board investigator, the pilot stated that the accident flight was the last flight of his 6-day workweek. He thought that his complacency and eagerness to finish the flight might have contributed to him misjudging the maneuver. He reported no mechanical malfunctions or failures with the helicopter prior to impact.

Aircraft

Registration
N6639R
Reported as
Hughes OH-6A
Category
Helicopter
Serial number
66-7874
Airframe hours
11,304
Engine
Rolls-Royce 250-C20B, 420 horsepower, turbo shaft
Damage
Substantial damage
Flight
Public aircraft · Public use
Operator
US Border Patrol
Registered owner
U.S Border Patrol Operations
Last inspection
AAIP · October 12, 2004 · 3 hours before
Departed
KIPL · Imperial, CA
Airport
L78 · Jacumba Airport

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
37
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane, Helicopter
Medical
Class 1, Valid Medical--no waivers/lim.
Last flight review
July 1, 2004
Seat
Right
Flight hours
2,514 total · 674 in this make and model · 2,095 as pilot in command · 155 in the last 90 days · 72 in the last 30 days · 5 in the last 24 hours

Weather

Conditions
Visual (VMC) · Night/dark
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
46 °F, dew point 18 °F
Altimeter
29.95 inHg

FAA reports on this event · 1

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

Other investigations on N6639R · 1

Matched to the same aircraft by N-number and date.