LAX04TA264

NTSB accident investigation · Bell 212HP · Chester, CA · May 25, 2004

Accident · No injuriesFinal report
Date
May 24, 2004, 20:30 local (May 25, 2004, 03:30 UTC)
Place
Chester, CA
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N362EHBell 212HP
Weather
Visual (VMC) · Dusk
Status
Completed · report July 7, 2005
Report
Approved by Office Director
Case key
59662

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 excessive use of the cyclic and collective controls in response to the helicopter's unexpected rocking motion, which led to a main rotor contact with the upper wire cutter mounted on the cabin roof. A factor in the accident was the rough, sloping nature of the landing zone chosen for the firebase.

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.

Miscellaneous/otherLanding - flare/touchdown
Terrain condition - rough/unevenFactor
Terrain condition - uphillFactor
Rotor system,main rotor blade - perforatedCause
Rotorcraft flight controls - improper use ofPilot in commandCause

Analysis

The helicopter's main rotor blade made contact with the upper wire cutter device during an attempted landing on a sloped landing zone. Upon arriving at the landing zone, the pilot selected an area to land clear from other aircraft and began the descent toward rough terrain with a slope of about 8 to 9 degrees. As the helicopter settled onto the skids, the nose pitched upward and the helicopter slid backward. The pilot quickly increased the collective and moved the cyclic forward in an effort to reestablish the hover. The helicopter began to stabilize in the hover and the pilot felt a shudder and heard a corresponding thump sound. The pilot landed in a different area and noted that it appeared that a portion of the skid had dug into the terrain. A main rotor blade had impacted the upper wire cutter device, leaving the blade damaged beyond repair. The owner reported no preimpact mechanical malfunctions or failures with the helicopter.

Factual narrative

On May 24, 2004, about 2030 Pacific daylight time, a Bell 212HP, N362EH, main rotor blade made contact with the upper wire cutter device during an attempted landing near Chester, California. The helicopter was registered to Era Aviation, Inc., and operated by the United States Forest Service as a public-use flight under the provisions of 14 CFR Part 133. The airline transport pilot, the sole occupant, was not injured; the helicopter sustained substantial damage. The local flight departed Chester Fire Base, Chester, at an unknown time for the purpose of firefighting operations. Visual meteorological conditions prevailed and a company visual flight rules (VFR) flight plan had been filed.

In a written statement, Era Aviation Inc., reported that the purpose of the flight was for the pilot to execute a water drop via the use of a 100-foot line with a Bambi bucket attached. After an uneventful drop, the pilot was instructed to touchdown at a landing zone (LZ) that had been previously been cleared. Upon arriving at the LZ, the pilot selected an area to land clear from other aircraft and began the descent toward rough terrain with a slope of about 8 to 9 degrees. As the helicopter touched down facing up the slope, the pilot lowered the collective, resulting in the helicopter rocking backward.

As the helicopter rocked backward, the pilot increased the collective in an effort to relocate to a level area and attempt the landing again. He repositioned the helicopter forward and touched down again, while lowering the collective and centering the cyclic. As the helicopter settled onto the skids, the nose pitched upward and the helicopter slid backward. The pilot quickly increased the collective and moved the cyclic forward in an effort to reestablish the hover. As the helicopter began to stabilize in the hover, the pilot felt a "shutter" and heard a corresponding "thump."

The pilot elected to land in a different area and shut down the engine. Upon exiting the helicopter, the pilot noted that it appeared that a portion of the skid had dug into the terrain. He did not complete a further examination of the helicopter because he did not think it incurred damage during the landing. He loaded the helicopter and returned back to Chester Fire Base without mishap.

During a routine daily inspection, the operator's aviation maintenance technician found that one of the main rotor blades was damaged. He noted that the blade appeared to have come into contact with the upper wire cutter device. The damaged blade was sent to Bell Helicopter for repair. They reported that the subject blade was damaged beyond repair.

Era Aviation Inc., reported no preimpact mechanical malfunctions or failures with the helicopter. They further stated that they had contracted the helicopter to the U. S. Forest Service. On this particular flight, the U. S. Forest Service had subcontracted the helicopter out to the California Department of Forestry for firefighting operations.

Aircraft

Registration
N362EH
Reported as
Bell 212HP
Category
Helicopter
Serial number
30853
Airframe hours
11,309.1
Engine
Pratt & Whitney PT6T-3B, 1,800 horsepower, turbo shaft
Damage
Substantial damage
Flight
Public aircraft · Public use
Operator
United States Forest Service
Registered owner
Era Helicopters Inc.
Airworthiness certificate
Standard, Normal
Last inspection
Continuous airworthiness · June 29, 2004 · 29.1 hours before
Departed
O05 · Chester, CA
Flight plan
Company VFR
Airport
Chester Fire Base

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
51
Injuries
None
Certificate
Airline transport
Instrument ratings
Helicopter
Medical
Class 1, Valid Medical--w/ waivers/lim
Last flight review
May 18, 2004
Seat
Left
Flight hours
8,730 total · 4,375 in this make and model · 6,275 as pilot in command · 33 in the last 90 days · 12 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Dusk
Wind
150° at 5 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
70 °F, dew point 52 °F
Altimeter
29.79 inHg
Observed at
RBL