Aviation Accident Summaries

Aviation Accident Summary WPR11FA319

Verlot, WA, USA

Aircraft #1

N8721C

PIPER PA-22-135

Analysis

The non-instrument rated pilot departed the airport for a 198-mile cross-country flight. Weather conditions at the departure airport were visual flight rules (VFR); however, the weather along the intended route of flight varied between VFR and instrument flight rules conditions. Weather satellite imagery from about 5 minutes before the time of the accident depicted an extensive area of low stratiform clouds throughout the area. No defined convective clouds were identified along the route of flight. The satellite images showed that clouds began about 50 miles east of the accident site and increased in coverage and thickness toward the intended destination. The images also depicted that an overcast layer of stratocumulus to nimbostratus clouds obscured the accident site. An area forecast for the day of the accident included a warning that the mountains would remain mostly obscured during the morning hours. It is likely that the pilot encountered clouds and failed to maintain terrain clearance. There was no record of official weather briefings, but the pilot may have obtained an unofficial weather brief from another source for the flight. Examination of the accident site via helicopter revealed that the airplane came to rest on steep sloping terrain just below a ridge line. The wreckage was mostly consumed by fire. An on scene examination of the airplane wreckage was not conducted due to terrain conditions and the wreckage was not recovered.

Factual Information

HISTORY OF FLIGHT On July 8, 2011, about 0905 Pacific daylight time, a Piper PA-22-135, N8721C, sustained substantial damage when it impacted terrain near Verlot, Washington. The airplane was registered to the pilot and operated under the provisions of Title 14 Code of Federal Regulations Part 91. The private pilot and his passenger sustained fatal injuries. Visual and instrument meteorological conditions prevailed within the vicinity of the accident and no flight plan was filed for the personal flight. The cross-country flight originated from a private airstrip near Elk, Washington, about 0520, with an intended destination of Arlington, Washington. Family members of the pilot reported that the pilot departed Elk, Washington with the intention of flying to Arlington to attend the Arlington fly-in. The pilot told family that he planned to go to Ellensburg, Washington, if the weather was bad along his intended route of flight. A family member of the pilot reported the airplane overdue to local law enforcement the morning of July 9, 2011, after becoming concerned when the pilot had not arrived at his intended destination. The Federal Aviation Administration (FAA) issued an Alert Notification (ALNOT) for the missing airplane. The wreckage was located by United States Navy Search and Rescue (SAR) personnel about 1400 on July 9 in heavily wooded mountainous terrain near Liberty Mountain. Review of recorded radar data revealed that a primary target attributed to the accident airplane began about 7 minutes after the approximate time of departure and 3 miles southwest of the departure airport. The data depicted a track in a west southwesterly heading until west of Chelan, Washington, where a right turn to a northwesterly heading was observed. The track continued on a northwesterly heading for about 1 hour, 18 minutes before a right turn to a northeasterly heading was observed. The track continued on a northeasterly heading for about 2 minutes. The last radar plot ended about 1.6 miles southwest of the accident site. PERSONNEL INFORMATION The pilot, age 45, held a private pilot certificate with an airplane single-engine land rating. An FAA third-class airman medical certificate was issued on July 22, 2009, with no limitations stated. The pilot reported on his most recent medical certificate application that he had accumulated 1,200 total flight hours. The pilot’s logbook was not located. AIRCRAFT INFORMATION The four-seat, high-wing, fixed-gear airplane, serial number (S/N) 22-1368, was manufactured in 1953. It was powered by a Lycoming O-290 series engine. No aircraft records were located. METEOROLOGICAL INFORMATION A National Transportation Safety Board (NTSB) staff meteorologist prepared a factual report for the area and surrounding the accident. The National Weather Service (NWS) Surface Analysis Chart for 0800 depicted a high pressure system off the Pacific northwest coast with a high pressure ridge extending eastward into Washington and Oregon. The station models surrounding the accident site indicated westerly wind at 10 knots or less and overcast sky conditions. The closest weather reporting facility to the accident site was the Arlington Municipal Airport automated weather observation station, located about 21 miles northwest of the accident site at an elevation of 142 feet mean sea level (msl). At 0855 the reported conditions were wind calm, visibility 10 statute miles, few clouds at 900 feet, scattered cloud layer at 4,900 feet, overcast cloud layer at 6,000 feet, temperature 12 degrees Celsius, dew point 9 degrees Celsius, and an altimeter setting of 30.19 inches of Mercury. The Geostationary Operational Environmental Satellite number 11 (GOES-11) infrared band 4 image at 0900 PDT (1600Z) on July 8, 2011 depicted an extensive area of low stratiform type clouds over western and central Washington. No defined convective clouds were identified along the route of flight. The radiative cloud top temperature over the accident site was observed at 266° Kelvin (K) or –7.16° C, which according to the KUIL sounding indicated cloud tops in the range of 7,500 to 12,000 feet. The GOES-11 visible image for 0900 at normal magnification showed that clouds begin approximately 50 miles east of the accident site and increase in coverage and thickness towards the west. At 2X magnification, the image depicted that an overcast layer of stratocumulus to nimbostratus type clouds obscured the accident site. The area forecast issued by the NWS at 0345 for Washington east of the Cascades was for sky clear and visibility unrestricted. Over the Cascades the forecast was for broken clouds at 5,000 to 6,000 feet with tops from 10,000 to 12,000 feet. For the Puget Sound and interior Mountains region near the planned destination broken clouds at 2,500 feet and broken to overcast clouds between 3,500 to 5,000 feet with tops between 8,000 and 10,000 feet. With the conditions becoming from 1000 to 1300, broken clouds at 5,000 to 6,000 feet with tops between 10,000 to 12,000 feet. The outlook from 1600 to 2200 was for VFR conditions to prevail. The NWS Seattle forecast office issued an area forecast discussion at 0234, providing their assessment of the conditions influencing the area. They indicated that an upper level low pressure system was expected to bring mostly cloudy skies and morning drizzle over western Washington. In the aviation section, the forecaster warned that the mountains would remain mostly obscured during the morning hours. For further information, see the Meteorological Factual Report within the public docket. WRECKAGE AND IMPACT INFORMATION Examination of the accident site by the NTSB investigator-in-charge (IIC) via helicopter revealed that the airplane came to rest on steep sloping terrain about 200 feet below a ridge line at an elevation of about 4,150 feet mean sea level (msl). The wreckage was mostly consumed by fire. An on scene examination of the airplane wreckage was not conducted due to terrain conditions and the wreckage was not recovered. MEDICAL AND PATHOLOGICAL INFORMATION The Snohomish County Medical Examiner conducted an autopsy on the pilot on July 12, 2011. The medical examiner determined that the cause of death was “...presumed multiple blunt-force injuries.” The FAA's Civil Aeromedical Institute (CAMI) in Oklahoma City, Oklahoma, performed toxicology tests on the pilot. According to CAMI's report, carbon monoxide, cyanide, volatiles, and drugs were tested, and had positive results for an unspecified amount of Ibuprofren within the urine.

Probable Cause and Findings

The non-instrument rated pilot’s decision to continue visual flight into clouds and his failure to maintain clearance from terrain while maneuvering in an area of reduced visibility, low clouds, and mountain obscuration.

 

Source: NTSB Aviation Accident Database

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