SEA05LA198

NTSB accident investigation · Cessna 170A · Ione, WA · September 21, 2005

Accident · FatalLimited investigationFinal report
Date
September 21, 2005, 16:50 local (23:50 UTC)
Place
Ione, WA
Injuries
1 fatal
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N9527ACessna 170A
Weather
Visual (VMC) · Day
Status
Completed · report February 28, 2006
Report
Approved by Office Director
Parties
Spokane FSDO
Case key
62522

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

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Probable cause

The pilot's failure during low-level maneuvering flight, to maintain clearance from a pair of unmarked power lines. Factors include the pilot's intentional low altitude flight/maneuver and wires.

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 objectManeuvering
Clearance - not maintainedPilot in commandCause
Low altitude flight/maneuver - intentionalPilot in commandFactor
Object - wire,transmissionFactor
Terrain condition - water

Analysis

After arriving in the area of the accident, the pilot first flew to the north while low over the trees along the side of the Pend Oreille River. He then reversed course and headed to the south about 100 feet or less over the river. As he proceeded south over the river, the aircraft impacted a pair of unmarked power transmission wires that run across the river. Immediately upon contacting the power lines, the aircraft's pitch attitude rotated to a near vertical position, and it descended nearly straight down into the river. In less than two minutes after hitting the surface of the river, the aircraft sank in about 10 feet of water. It was later determined that the power lines were between 80 and 90 feet above the surface of the river. An inspection of the aircraft revealed wires had contacted the propeller, the lower portion of the fuselage just aft of the door frames, and the vertical stabilizer leading edge where it intersects the fuselage. Control continuity was established to the elevator, and there was no indication that there had been any anomaly associated with the engine.

Factual narrative

On September 21, 2005, approximately 1650 Pacific daylight time, a Cessna 170A, N9527A, impacted power lines crossing the Pend Oreille River about one mile north of Box Canyon Dam, near Ione, Washington. The airline transport pilot, who was the sole occupant, received fatal injuries, and the aircraft, which is owned and operated by the pilot, sustained substantial damage. The flight was operating in visual meteorological conditions at the time of the accident. The aircraft was last seen at the Lake Sullivan State Airstrip, and it reportedly departed there about 30 minutes prior to the accident. It is believed that the pilot was on a local pleasure flight, with an intended ultimate return to Lake Sullivan. There was no report of an ELT activation. No flight plan had been filed.

According to witnesses, the aircraft was first noticed going to the north, flying low over the trees along the side of the Pend Oreille River. It then reversed course and headed to the south at 100 feet or less above the river. The aircraft was then seen to impact a pair of unmarked power transmission wires that run across the river about one mile north of the Box Canyon Dam. Immediately upon contacting the power lines, the aircraft's pitch attitude rotated to a near vertical position, and it descended nearly straight down into the river. In less than two minutes after hitting the surface of the river, the aircraft sank in about 10 feet of water. It was later determined that the power lines were between 80 and 90 feet above the surface of the river.

An inspection of the aircraft after it was recovered from the river revealed wire strike abrasions on the propeller, the lower portion of the fuselage just aft of the door frames, and at the point where the vertical stabilizer leading edge intersects the fuselage. Control continuity was established to the elevator, and there was no indication that there had been any anomaly associated with the engine.

An autopsy performed by the Pend Oreille County Corner determined that the pilot died as a result of blunt force impact to the head and torso, and that the cause of death was accidental. A forensic toxicology performed by the FAA's Bioaeronautical Science Research Laboratory was negative for carbon monoxide, cyanide, ethanol, and screened drugs.

Aircraft

Registration
N9527A
Reported as
Cessna 170A
Category
Airplane
Serial number
19088
Engine
Continental O-300, 145 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Registered owner
Hans C. Henrickson
Airworthiness certificate
Standard, Normal
Departed
095 · Sullivan Lake, WA
Destination
095 · Unknown, WA

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
57
Injuries
Fatal
Certificate
Airline transport
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Helicopter
Medical
Class 2, With waivers/limitations
Seat
Left
Toxicology
Performed
Flight hours
24,000 total

Weather

Conditions
Visual (VMC) · Day
Wind
360° at 5 knots
Visibility
15 statute miles
Lowest ceiling
None
Temperature
61 °F