Accident Details
Probable Cause and Findings
The pilot's failure to maintain clearance from terrain while maneuvering. Mountainous terrain, trees and mountain obscuration were factors.
Aircraft Information
Registered Owner (Historical)
Analysis
HISTORY OF FLIGHT
On April 17, 2003, a twin-engine Cessna 320D, N4178T, registered to and flown by an instrument rated commercial pilot as a 14 CFR Part 91 personal flight, failed to arrive at the Bellingham International Airport, Bellingham, Washington, their presumed destination, after departing the Pangborn Memorial Airport, Wenatchee, Washington. Variable meteorological conditions prevailed over the route of flight to Bellingham, and a flight plan was not filed. It was reported by witnesses at Wenatchee that the flight departed at approximately 0745. One passenger was on board.
Witnesses reported that the aircraft arrived in Wenatchee on April 16, 2003. Fuel was added to the aircraft by Wings of Wenatchee at 1530. On April 17, 2003, witnesses observed two people loading baggage onto the aircraft sometime before 0800. The aircraft took off from Wenatchee about 0745.
Family members reported that this was a pleasure flight, and that the pilot and passenger were friends. The wife of the pilot stated that she believed that her husband was going to Bellingham before returning to California. The wife also reported that the pilot liked to fly low to look at the country side.
On April 18, 2003, at 1557, an alert notice (ALNOT) was issued for the missing aircraft. Search and rescue efforts commenced on April 19, 2003. During the search efforts, radar targets to the north and south of Wenatchee were researched. None of the targets were identified as the missing aircraft. The aircraft was not located and the search was suspended on May 1, 2003.
During the search effort, two witnesses reported seeing a white twin-engine aircraft on the morning of the accident. One witness reported seeing the aircraft at about 0815 flying northbound up the Columbia River, near Entiat, Washington, at about 200 feet above ground level. The other witness was a pilot conducting a scenic flight from the Twisp, Washington, airport. This pilot reported that he was descending from altitude south of Carlton, Washington. The pilot observed a twin engine aircraft flying northbound up the Methow River south of Carlton at an altitude between 200 and 500 feet above ground level. The pilot last saw the aircraft north of the Winthrop, Washington, airport.
On August 8, 2003, approximately 1030 Pacific daylight time, a helicopter pilot engaged in fire-fighting operations spotted the wreckage in a valley located 13 miles north of Mazama, Washington. The wreckage was positioned on the east wall of the north/south running valley at the approximate 5,000 foot level. Both occupants were fatally injured at the time of the accident.
A Global Positioning System GPSMAP 295 was recovered from the accident site on August 12, 2003. The unit was in good physical condition and was subsequently sent to Garmin International for data extraction. The Product Support Supervisor reported that the last point the unit recorded was at N48 degrees 47.590 minutes, W120 degrees 33.936 minutes. The unit listed a track of 342 degrees magnetic, with a distance of 80.2 to go, with a course of 337 degrees magnetic to Merritt, British Columbia. An altitude of 5,243 feet was recorded at a maximum speed of 197 knots, with a trip odometer of 103 nautical miles, and a trip time of 3 hours, 37 minutes. A moving average speed was recorded of 164 knots. The unit did not contain any routes or track log information. The track log recording was turned off.
Four waypoints were recorded. Three of the waypoints were plotted near Klamath Falls, Oregon. The fourth waypoint was located 18 nautical miles southeast of the accident site at an altitude of 2,284 feet.
PERSONNEL INFORMATION
At the time of the accident, the pilot held a commercial flight certificate for single and multi-engine land aircraft, with an instrument rating. The pilot also held a flight instructor certificate for single-engine aircraft.
The last FAA medical certificate was issued on November 12, 1999, for Class III privileges with a limitation for the pilot to wear corrective lenses. At this time the pilot reported a total flight time of 6,000 flight hours, with no flight time in the preceding six months. To this date, the pilot's flight logbook has not been located.
The passenger held a student pilot certificate that was issued on February 24, 2003, at the time of his issuance of a Class III FAA medical certificate. At the time, the passenger indicated a total flight time of 94 hours with 45 hours in the preceding six months.
AIRCRAFT INFORMATION
Records obtained from the FAA indicated that the pilot purchased this aircraft in 1986. Maintenance logbooks indicated that the last annual inspection was on September 11, 1997, at a total airframe time of 3,693.5 hours, and hobbs time of 938.5 hours. At the time of the accident, the hobbs time indicated 1,369.9. Approximately 431 hours had been accumulated on the aircraft since the last annual inspection.
The last fuel receipt located from Wings of Wenatchee, Inc., East Wenatchee, Washington, indicated that the main fuel tanks were topped off with 100LL fuel on April 16, 2003, for a total of 109.6 gallons.
This aircraft was equipped with standard main fuel tanks (total capacity 102 gallons), and auxiliary fuel tanks (total capacity 143 gallons). Locker tanks had also been installed in each engine nacelle. There was no entry in the aircraft logbooks to indicate when and by whom these locker tanks were installed.
METEOROLOGICAL INFORMATION
The area forecast for September 17, 2003, was issued at 0345 local, and valid until 2200, for Washington, Oregon, California and coastal waters. Washington interior sections reported scattered clouds at 2,000 feet, and broken at 3,000 feet, with layered clouds to 12,000 feet with occasional light rain showers. The outlook reported marginal visual flight rules.
East of the Washington Cascades reported scattered clouds at 8,000 feet, with broken clouds at 12,000 feet. Widely scattered clouds with light rain showers east and south. The outlook indicated VFR with rain showers.
Airmet Zulu valid until 1300 local for Washington and Oregon reported icing conditions. The freezing level for the area west of the Cascades was 2,500 to 3,000 feet. The area east of the Cascades was from 4,000 feet to 5,000 feet.
Updated Airmet Sierra indicated Instrument Flight Rules (IFR) and mountain obscuration until 1300.
The surface weather reported at 0755 for Wenatchee, indicated winds from 250 degrees at six knots. Visibility was 10 statute miles. The temperature was 7 degrees C, and the dew point was 2 degrees C. The sky was overcast at 8,000 feet. The altimeter setting was 29.83" Hg.
WRECKAGE AND IMPACT INFORMATION
An on site examination of the wreckage was conducted on August 12, 2003, by investigators from the National Transportation Safety Board, Federal Aviation Administration, and Cessna Aircraft Company. Also present were two Okanogan County Sheriff's Office personnel.
The wreckage was located on the east wall of a north/south running valley identified as Eureka Creek. The elevation of the accident site utilizing a hand held GPS unit indicated 5,083 feet. The accident site coordinates were N 48 degrees 47.589 minutes latitude, W 120 degrees 33.933 minutes longitude. The terrain angle was estimated as 45 degrees. The ground was covered with thick brush and tall evergreen trees measuring in height to approximately 100 feet. The valley walls above the accident site and the terrain to the north rose to approximately 8,000 feet. Aerial views of the accident site identified several tree tops that were damaged to the south of the main wreckage. Trees to the north and slightly downhill of the main wreckage indicated heat distress. Wreckage noted along the damaged tree path leading up to the main wreckage were later identified as the right side outboard section of the horizontal stabilizer and outboard section of the right side elevator. Approximately 300 feet of damaged tree tops and brush were measured leading up to the main wreckage. The magnetic heading measured along this path was 320 degrees. Approximately 75 feet beyond the main wreckage following the 320 degree heading, a section measuring approximately 52 inches of the left wing aileron was located slightly downhill. Approximately 25 feet further, the section of left wing outboard of the engine nacelle was located. This section displayed heat distress. The trees in the immediate vicinity of this section were fire damaged.
The main wreckage was oriented with the nose pointing to 90 degrees. The wreckage was laying flat on its belly with the nose uphill. The landing gear was retracted. Both inboard sections of the wings remained attached at the wing roots. The right engine, although laying inverted, remained partially attached to the firewall. The right wing area leading edge outboard of the engine was crushed aft and displayed heat distress. The aft section of the right wing was located on the left side of the wreckage. The structure was severely deformed.
The right engine valve covers were removed to verify that all rocker arms and associated hardware was intact. Top spark plugs from cylinders 2, 4, and 6 were removed. The electrodes were oil soaked due to the engine being inverted.
The right engine propeller assembly remained attached to the crankshaft and both propeller blades remained attached to the hub. The right engine propeller blade "A" displayed "S" bending with the outboard 8 inches of the tip missing. The tip was later located uphill in the brush about 30 feet from the main wreckage. Propeller blade "B" displayed an even aft bending arc with a tight curl at the blade tip.
The left wing inboard section to include the engine remained attached at the wing root. The engine remained in place and partially enclosed in the engine nacelle. Evidence of impact with a tree was noted along the leading ed...
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# SEA03FA165