Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms
NTSB Identification: WPR11FA350
14 CFR Part 91: General Aviation
Accident occurred Monday, July 25, 2011 in Chelan, WA
Probable Cause Approval Date: 07/23/2013
Aircraft: SIKORSKY S-55B, registration: N5663
Injuries: 1 Fatal.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
The helicopter was contracted to overfly the rural cherry orchard in order to dry the cherries following rain showers. A witness reported that the helicopter was flying over the cherry orchard from south to north, and it had just completed a left turn when it collided with power lines that bordered the orchard. The helicopter impacted terrain, in a nose low attitude, about 45 feet south of the power lines. Power line wires were found wrapped 3 to 4 times around the main rotor mast and striation marks on the leading edge of the main rotor blades were indicative of a wire strike.
Examination of the accident site revealed that four wires were strung between poles with the top three wires about 50 feet agl and the lower wire about 40 feet agl. Postaccident examination of the airframe and engine revealed no evidence of a preimpact mechanical malfunction or failure that would have precluded normal operation.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot’s failure to maintain clearance from power lines while maneuvering at a low altitude.
HISTORY OF FLIGHT
On July 25, 2011, about 1438 Pacific daylight time, a Sikorsky S-55B Helicopter, N5663, sustained substantial damage after colliding with powerlines and impacting terrain near Chelan, Washington. The helicopter was registered to Golden Wings Aviation and operated under the provisions of Title 14 Code of Federal Regulations Part 91. The commercial pilot, who was the sole occupant of the helicopter sustained fatal injuries. Visual meteorological conditions prevailed and no flight plan was filed for the flight. The local flight originated from a staging area near the accident site about 10 minutes prior to the accident.
A witness reported that the helicopter was flying over the cherry orchard from south to north, and just completed a left turn when it collided with the powerline. The witness reported the helicopter then descended out of view after the collision; however, seconds later, he observed a large cloud of black smoke near the area where the helicopter was maneuvering.
The helicopter was contracted to overfly the rural cherry orchard in order to dry the cherries following a rain shower, and was engaged in cherry drying operations when the accident occurred.
PERSONNEL INFORMATION
The pilot, age 22, held a commercial pilot certificate with rotorcraft-helicopter and instrument ratings. Additionally, he held a flight instructor certificate, with a rotorcraft-helicopter rating. His most recent first-class airman medical certificate was issued May 5, 2011, with a restriction that he is required to wear corrective lenses. The pilot's logbook was not recovered for examination. The operator reported that the pilot’s total rotorcraft-helicopter flight time was 1,192 hours, with 50 hours in accident make and model.
AIRPLANE INFORMATION
The accident helicopter, a Sikorsky S-55B, was manufactured in 1959 and powered by a Wright R-1300 radial engine rated at 800 HP. The helicopter was configured with a three blade main rotor system, and conventional tail rotor. The maximum gross takeoff weight for the restricted category helicopter was 7,200 pounds.
The helicopter’s most recent inspection, an annual inspection, was completed June 1, 2011, at a total airframe time of 7,397 hours; the engine total time since overhaul at the inspection was 13 hours.
METEOROLOGICAL INFORMATION
At 1455, the reported weather conditions at Pangborn Memorial Airport, Wenatchee, WA, located about 35 miles south of the accident site, at an elevation of 1,229 feet, were winds from 300 degrees at 8 knots, clear skies, visibility 10 miles, temperature 23 degrees Celsius (C), dew point 14 degrees C, and altimeter setting 29.91 inches of mercury.
WRECKAGE AND IMPACT INFORMATION
Examination of the accident site revealed that the helicopter impacted terrain, in a nose low attitude, approximately 45 feet south of the powerlines. A postcrash fire ensued.
The initial point of impact was a series of power delivery lines that ran northwest to southeast along the northern perimeter of the orchard. The wire span between the two nearest support poles was approximately 800 feet. Four wires were strung between the two poles, with each of the four wires consisting of a bundled complex of six individual wires. Three wires were situated coplanar to each other while the third was located vertically beneath. The height of the top three wires was approximately 50 feet, while the bottom wire was approximately 40 feet.
The main wreckage was located in the confines of a burn area approximately 45 feet south of the powerlines. The cockpit, instrument panel, pedestal and cabin area sustained extensive impact and thermal related damage.
The helicopter rotor system consisted, in part, of three blades; each blade was found attached to the helicopter rotor hub assembly. The powerline wires were wrapped 3-4 times around the main rotor swash plate and rotor mast. All dampeners were detached from the rotor blades; two of the pitch change (PC) links were completely detached from the main rotor hub, while the third PC link was bent. All fracture surfaces associated with the mast assembly appeared to be the result of overstress separation.
Striation marks, indicative of a wire strike, were noted on the leading edge (full span) of blades A and C. Numerous strands of powerline wire were located in the general area of the main wreckage. The wires showed a tension-like failure mode.
A postaccident examination of the airframe and engine revealed no evidence of a preimpact mechanical failure that would have precluded normal operations.
MEDICAL AND PATHOLOGICAL INFORMATION
The FAA's Civil Aerospace Medical Institute, Oklahoma City, Oklahoma, performed toxicological testing on the pilot. Fluid and tissue specimens tested negative for cyanide, ethanol, and tested drugs.
SURVIVAL ASPECTS
An autopsy was performed on the pilot on July 26, 2011, at Central Washington Hospital. The postmortem report attributed the pilot’s cause of death to asphyxia due to inhalation of products of combustion.
ADDITIONAL INFORMATION
A review of the pilot’s cellular telephone phone records revealed that his phone was active on the day of the accident; however, no outgoing text messages or telephone calls were documented between 1430 and the time of the accident.
CHELAN, Wash. -- A pilot who died last summer when his helicopter crashed in a Chelan orchard while he was drying cherries from rain may have been text messaging or talking on his cell phone at the time of the crash, a lawsuit alleges.
"Apparently, he was either talking on the phone or texting on the phone while he was flying and unfortunately caught part of his helicopter on a powerline," said Dale Foreman, a Wenatchee attorney representing Chelan View Orchard Inc.
Chelan View, a neighboring orchard to the crash site, is suing Golden Wings Aviation of Brewster and its owners, Dave Smith, Sr., and Dave Smith, Jr. The suit in Chelan County Superior Court alleges breach of contract for not drying cherries and seeks $466,323 in crop loss, plus attorney fees and court costs. Chelan View is owned by John Marker.
"Our client talked to two neighbors, also cherry growers who also were waiting for their cherries to be dried, who received text messages from the pilot just before the crash," Foreman said.
Calling and text messaging while flying is against Federal Aviation Administration regulations and amount to negligence, the lawsuit states.
"That's unfounded and ridiculous. He wouldn't do that. It's physically impossible," said Dave Smith, Sr. A helicopter pilot constantly uses both hands when airborne.
Dennis Hogenson, the investigator of the crash for the National Transportation Safety Board, said he's aware of the texting allegation but can't comment. He said he hopes to issue a report in a month.
Preliminary NTSB findings shortly after the crash found that it was caused by striking power lines and that no mechanical failure was involved.
The crash occurred July 25. The helicopter banked at the end of the orchard to turn back over the orchard when it struck two of four power lines about 50 feet above the cherry trees, Detective Sgt. Jerry Moore, of the Chelan County Sheriff's Office, said at the time.
"The rotors came to a complete stop and the helicopter came straight down. That's what a witness told us," Moore said.
The helicopter's fuel tank exploded and the helicopter burst into flames upon impact. The pilot, Stephen W. Nelson, 22, Indianapolis, Ind., was badly burned. An autopsy showed he died of smoke inhalation.
The lawsuit alleges that a second helicopter did not arrive to dry Chelan View's cherries for several hours, by which time the fruit was split and ruined.
Smith's attorney, West Campbell, Yakima, declined comment other than to say the allegations in the lawsuit are only allegations.
"It was devastating to lose a pilot. In my 40 years of flying we'd never had that happen," Smith said.
He said the flying service is still operating and plans to work this year's cherry season.
Foreman said Golden Wings' insurance company, John Jaeger Co., Elkgrove, Calif., ordered a partial picking of the damaged crop to establish the loss. That was done, he said, but Jaeger did not pay the claim.
NTSB Identification: WPR11FA350
14 CFR Part 91: General Aviation
Accident occurred Monday, July 25, 2011 in Chelan, WA
Aircraft: SIKORSKY S-55B, registration: N5663
Injuries: 1 Fatal.
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.
On July 25, 2011, about 1438 Pacific daylight time, a Sikorsky S-55B Helicopter, N5663, sustained substantial damage after colliding with power lines and impacting terrain near Chelan, Washington. The helicopter was registered to Golden Wings Aviation and operated under the provisions of Title 14 Code of Federal Regulations Part 91. The commercial pilot, who was the sole occupant of the helicopter sustained fatal injuries. Visual meteorological conditions prevailed and no flight plan was filed for the flight. The local flight originated from a staging area near the accident site about 10 minutes prior to the accident.
A witness reported that the helicopter was traveling from south to north. He reported that the helicopter was in a left turn when it collided with the power line. The witness reported the helicopter descended out of view after striking the power lines; however, seconds later, he observed a large cloud of black smoke near the area where the helicopter was maneuvering.
Examination of the accident site revealed that the helicopter impacted terrain, in a nose low attitude, approximately 45 feet south of the power lines. A post crash fire ensued.
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