History of Flight
On August 13, 2010, at approximately 1245 Pacific daylight time, a Piper PA-28R-201, registration N3463Q, impacted pine trees and terrain in the Tahoe National Forest, near Emigrant Gap, California. The aircraft, operated by Monterey Bay Aviation, Inc., was conducting a cross-country flight under 14 CFR Part 91. The purpose of the flight was to provide mountain flying training for the private pilot.
The flight originally departed Watsonville Municipal Airport (WVI) around 1030 with an instrument flight rules (IFR) flight plan filed, destined for Auburn Municipal Airport (AUN). After landing at Auburn, the pilots obtained refreshments and departed again about 1215. No flight plan was filed for this leg.
Witnesses at the Tunnel Mills campsite observed the airplane flying low, just above treetops, on a heading of 120 degrees between 1230 and 1300. The engine sounded normal with no sputtering. After the airplane disappeared from view, two bangs were heard, followed by silence. Campers located the accident site and notified the California Highway Patrol.
Personnel Information
The certified flight instructor (CFI), aged 32, held a flight instructor certificate with ratings for airplane single-engine land and sea, multiengine land, and instrument airplane. He held a third-class medical certificate issued July 7, 2008, with no limitations. His total flight time was 2,755 hours as of July 2008, with 150 hours in the previous six months. In the days before the accident, he flew with the private pilot four times: once on July 12 (1.1 hours) and three times on August 12 (3.5 hours).
The private pilot, aged 21, held a private pilot certificate with ratings for airplane single-engine land and instrument airplane. He held a first-class medical certificate issued September 2, 2008, with no limitations. His logbook indicated an estimated total flight time of 332 hours, with 19 hours in the four months before the accident, including 3.5 hours in the accident make and model. He had flown with the CFI four times: a checkout on July 12, and three flights on August 12 for canyon and mountain flying instruction.
It could not be determined who was manipulating the flight controls at the time of the accident.
Aircraft Information
The aircraft was a Piper PA-28R-201, serial number 28R-7737055. Total airframe time at the last annual inspection (March 1, 2010) was 8,447.48 hours. The engine, a Lycoming IO-360-C1C6 (serial number L-22246-51A), was installed on August 7, 1999, replacing the original engine that had a cracked crankcase.
Meteorological Information
The nearest weather reporting station, Blue Canyon Nyack Airport (located 3.9 miles northwest of the accident site), reported at 1352: wind from 310 degrees at 5 knots, clear skies, temperature 23°C, dew point 8°C, altimeter 30.07 inHg, and density altitude 6,582 feet. At 1152, conditions were wind 270 degrees at 4 knots, clear skies, temperature 22°C, dew point 9°C, and altimeter 30.07 inHg.
Wreckage and Impact Information
The accident site was located in a remote area of the Sierra Nevada Mountain Range, north of Sawtooth Ridge, half a mile east of a campsite, at an elevation of 4,700 feet. The main wreckage came to rest inverted at the base of 200-foot pine trees adjacent to an old logging road, on a heading of 114 degrees, in rising terrain. The wreckage was distributed linearly over 110 yards. The main wreckage comprised the fuselage, empennage, right wing, and part of the left wing. The outer 5 feet of the left wing separated and was found 90 yards west. The engine, firewall, and propeller assembly came to rest 20 yards east.
Tree strikes indicated the airplane was in a 33-degree nose-up attitude (consistent with a climb) and an 18-degree left bank at impact. Another tree strike on the left side of the instrument panel separated the panel, right front seat, cabin door, forward cabin floor, and right wing.
Medical and Pathological Information
Autopsies performed by the Placer County Sheriff-Coroner listed cause of death for both pilots as multiple blunt-force trauma. Toxicology testing of the CFI revealed Delta-9 THC (2.5 ng/mL) and Delta-9 Carboxy THC (8.7 ng/mL) in femoral blood; also present were caffeine, cotinine, nicotine, and theobromine. Further testing detected tetrahydrocannabinol (marihuana) in lung, kidney, and blood cavity specimens. The private pilot's specimens were negative for carbon monoxide, cyanide, and ethanol; an unspecified amount of cetirizine (an antihistamine) was found in urine and blood.
Tests and Research
Postaccident examination of the airframe and engine found no evidence of mechanical malfunctions or failures that would have precluded normal operation. Flight control continuity was established to all primary controls. The stabilator pitch trim drum showed 5 threads upper extension, consistent with a neutral setting. The engine examination revealed impact damage but no pre-impact abnormalities: spark plugs were normal, magnetos produced spark, fuel was present at flow divider and injectors, and no water was found in the fuel. The propeller showed bending and gouging consistent with impact with trees and terrain.