N323PAPiper PA-32R-301T · 2001

On December 22, 2015, about 1127 Pacific standard time, a Piper PA-32R-301T, N323PA, was destroyed when it impacted terrain near Castro Valley, California, while conducting an instrument approach to Metropolitan Oakland International Airport (OAK), Oakland, California. The private pilot was fatally injured. Instrument meteorological conditions (IMC) were present in the area, and an instrument flight rules (IFR) flight plan was filed for the flight, which departed Lincoln Municipal Airport (LHM), Lincoln, California, about 1050. The airplane was owned and operated by the pilot, and the personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91.

Air traffic control radar and voice communication information from the Federal Aviation Administration (FAA) revealed that the pilot contacted the Northern California Terminal Radar Approach Control facility shortly after takeoff from LHM and requested an IFR clearance to OAK. The pilot was subsequently issued a discrete transponder code and an IFR clearance. About 1122, as the airplane neared the destination, it was established on a heading of 160° at an altitude about 4,000 ft mean sea level (msl). The controller cleared the pilot for the instrument landing system (ILS) approach to runway 28R, instructing him to turn right to a heading of 260° to intercept the localizer course and to descend and maintain an altitude of 3,400 ft msl until established on the approach. The controller told the pilot that the airplane was 1 mile north of the GROVE fix along the approach. According to radar data, at that point, the airplane was 1 mile north of NAGVY, a fix along the approach that was about 3 miles outside of GROVE (see figure 1).

Figure 1 - Approach Overview

The pilot acknowledged the clearance and began descending but did not initiate the right turn. About 30 seconds later, the controller contacted the pilot and provided a heading of 300° to cross and intercept the localizer. The pilot acknowledged, and the airplane began turning right (about 1123; see figure 2). During the turn, the airplane crossed the localizer course, then tracked toward the airport on the south side of the localizer course. About 1124, the controller asked the pilot if he had obtained visual contact with the airport, and the pilot replied, "I'm still in the weather." About 1125, the controller asked the pilot if the airplane was established on the localizer, to which the pilot replied, "I'm re-establishing." When the controller subsequently asked the pilot if he was receiving the glideslope indication, the pilot stated that he was receiving the glideslope but was "off glideslope" and "too high." At this time, the airplane's altitude was 2,600 ft msl; the minimum altitude for that segment of the approach was 3,400 ft msl.

The controller issued a low altitude alert, cancelled the approach clearance, and instructed the pilot to turn right to a heading of 300° and to climb and maintain an altitude of 4,000 ft msl. The pilot acknowledged; however, the airplane began a left turn to the south and did not climb. The controller subsequently instructed the pilot to turn north to a heading of 360° and asked the pilot to verify that the airplane was climbing and turning north. The pilot replied, "360 and climbing." The airplane made a right turn to the north and climbed to 3,700 ft before it began descending. Shortly after, during a partially-blocked transmission, the pilot stated, "I'm losing it." No further transmissions were received from the airplane, and radar contact was subsequently lost.

Figure 2 - Airplane's Flight Path (Localizer Course Depicted in Red)

The pilot held a private pilot certificate with ratings for airplane single-engine land and instrument airplane. He held an FAA third-class medical certificate, which was issued in August 2015 with a limitation requiring the use of corrective lenses. Review of the pilot's logbook indicated that he had accumulated about 1,262 total hours of flight experience, of which about 960 hours were in the accident airplane make and model. The pilot had accumulated about 43 total hours of actual instrument flight experience, 3.5 hours of which were in the 6 months before the accident, and about 82 hours of simulated instrument experience. His most recent flight review and instrument proficiency check were conducted on November 21, 2015.

The airplane was manufactured in 2001 and registered to the pilot in July 2007. It was equipped with a Lycoming TIO-540-AH1A, 300-horsepower, turbocharged, reciprocating engine, which drove a Hartzell HK732B constant-speed propeller. Review of maintenance logs indicated that the airplane's most recent annual inspection was completed on November 17, 2015, at a total airframe and engine time of 1,479.8 hours. The airplane was equipped with Garmin 430 and 530 panel-mounted GPS units, an electrically-driven standby attitude indicator, and a two-axis autopilot system, which interfaced with the airplane's horizontal situation indicator (HSI).

The 1126 automated weather observation at Livermore Municipal Airport (LVK), Livermore, California, located about 8 miles east of the accident site, included wind from 260° at 15 knots, 10 miles visibility, broken cloud layers at 1,300 and 3,200 ft, temperature 15°C, dew point 12°C, and an altimeter setting of 29.82 inches of mercury.

The 1154 automated weather observation at Hayward Executive Airport (HWD), Hayward, California, located about 7 miles west of the accident site, included wind from 270° at 11 knots, 9 miles visibility, broken ceiling at 3,900 ft, overcast ceiling at 5,000 ft, temperature 14°C, dew point 12°C, and an altimeter setting of 29.85 inches of mercury.

A weather computer model balloon sounding for the accident site about 1100 showed clouds likely from the surface through 6,000 ft msl, with drizzle and light rain. Weather satellite information about the time of the accident showed clouds over the area of the accident site moving northwest to southeast. Weather radar animation for the area of the accident site at the time of the accident showed light precipitation.

The area forecast, issued at 0345 and valid through the time of the accident, included overcast ceilings at 1,000 ft above ground level (agl) and visibilities of 3 to 5 miles in light rain and mist.

AIRMET advisories issued between 0645 and 0730, valid for the time of the accident, warned of moderate turbulence below 18,000 ft msl, IMC due to precipitation and mist, and mountain obscuration. Instrument conditions were forecast to improve between 1000 and 1300; however, the mountain obscuration conditions were forecast to continue beyond 1300.

The airplane was manufactured in 2001 and registered to the pilot in July 2007. It was equipped with a Lycoming TIO-540-AH1A, 300-horsepower, turbocharged, reciprocating engine, which drove a Hartzell HK732B constant-speed propeller. Review of maintenance logs indicated that the airplane's most recent annual inspection was completed on November 17, 2015, at a total airframe and engine time of 1,479.8 hours. The airplane was equipped with Garmin 430 and 530 panel-mounted GPS units, an electrically-driven standby attitude indicator, and a two-axis autopilot system, which interfaced with the airplane's horizontal situation indicator (HSI).

The accident site was located on a heavily-wooded hillside about 12 nautical miles southeast of OAK at an elevation about 1,400 ft. The initial impact point was identified by several fallen trees and large branches. From the initial impact point, the wreckage path extended downhill about 300 ft on a magnetic heading about 330°. The cockpit and cabin area was largely consumed by a post-crash fire.

The wreckage was recovered to a secure facility for examination due to its heavy fragmentation and the difficult terrain at the accident site. All major components of the airplane were accounted for during reconstruction of the wreckage, and there was no evidence of an inflight breakup.

The cabin and cockpit area, including all flight instruments and the autopilot, were destroyed by impact and fire. The left and right aileron control cables remained attached to the control chain. Both stabilator cables remained attached to the lower stabilator t-bar assembly. The left and right rudder control cables remained attached to the rudder control arm assemblies.

The left and right wings were separated from the fuselage at their respective roots and displayed varying degrees of impact and fire damage. Neither left nor right wing aileron bellcrank stops exhibited indications of flutter, and all control cable separations exhibited signatures of overstress. The fuel selector was in the left tank position, and the filter was free of contaminants. The fuel system was breached in multiple locations. The landing gear down-locks displayed no damage, consistent with the landing gear having been in a retracted position at the time of impact. Measurement of the wing flap actuator threads corresponded to a flaps-retracted position.

The empennage displayed significant impact damage and was separated into several sections. The right side horizontal stabilizer exhibited thermal damage. Both stabilator cables remained attached to the stabilator arm assembly, and the left and right rudder cables remained attached to the rudder bellcrank assembly.

The propeller was separated from the engine at the crankshaft flange. All three propeller blades remained attached at the hub and exhibited varying degrees of torsional twisting and s-bending. The propeller governor remained attached at its mounting pad with the pitch control rod securely attached to the control wheel. The governor was removed for examination; the drive was intact and free to rotate, and the gasket screen was free of contamination.

The engine was separated from its mounts and displayed significant impact damage to the Nos. 1, 3, and 5 cylinders. The No. 1 cylinder rocker assemblies were absent. The No. 3 cylinder head was impact separated, leaving only the barrel in place. The No. 5 cylinder was completely separated from the engine; the piston remained in place. Due to impact damage, the crankshaft could not be rotated by hand. The spark plugs were removed (except for those from the No. 3 cylinder, which were not located), and all displayed normal wear. The Nos. 2, 4, and 6 cylinder rocker covers were removed, and the rocker boxes displayed no anomalies. The Nos. 2, 4, and 6 cylinder combustion chambers were examined with a borescope and exhibited no anomalies.

Holes were drilled through the engine case to facilitate internal examination of the connecting rods, crankshaft, and camshaft, which revealed no evidence of any preimpact mechanical malfunctions or anomalies.

All accessories were separated from the engine. The accessory case was removed, and the accessory gears, including the crankshaft gear, bolt, and dowel, were intact and undamaged. The left and right magnetos were destroyed. The primary vacuum pump was separated from the engine, and its drive and rotor/vanes were not located. The standby vacuum pump was disassembled for examination and its internal components displayed damage consistent with impact.

The turbocharger system components were displaced from their mountings and exhibited impact damage. There was no evidence of foreign object ingestion. The wastegate remained intact and undamaged. The turbocharger housing exhibited signatures of rotation at the time of impact.

The fuel injection servo was impact separated. The throttle plate and shaft with attached control arm were separated from the servo. The throttle and mixture controls were found securely attached. The fuel inlet screen was free of contamination. The servo was disassembled and no anomalies were noted. The fuel flow divider remained secured to its mounting bracket, but all fuel lines were damaged or separated on impact. The flow divider was disassembled and no anomalies were noted.

The fuel pump was separated from the engine, though a portion of its mounting flange remained attached to the engine. The fuel pump was disassembled, and the rotor and vane assembly remained intact and free to rotate. The diaphragm was torn, and it was retained for further examination.

Fuel Pump Diaphragm

The fuel pump diaphragm was examined at the NTSB Materials Laboratory. Scanning electron microscope imagery of the tear in the diaphragm revealed signatures consistent with tensile overstress as a result of impact forces.

Spatial Disorientation

The FAA Civil Aeromedical Institute's publication, "Introduction to Aviation Physiology," defines spatial disorientation as a loss of proper bearings or a state of mental confusion as to position, location, or movement relative to the position of the earth. Factors contributing to spatial disorientation include changes in acceleration, flight in IMC, frequent transfer between visual meteorological conditions (VMC) and IMC, and unperceived changes in aircraft attitude. The publication states that pilots flying in IMC are more susceptible than usual to the stresses of flight, such as fatigue and anxiety, and any event that produces an emotional upset is likely to disrupt the pilot's mental processes, making them more vulnerable to illusions and false sensations.

The FAA's Airplane Flying Handbook (FAA-H-8083-3A) describes some hazards associated with flying when the ground or horizon are obscured. The handbook states, in part: "The vestibular sense (motion sensing by the inner ear) in particular tends to confuse the pilot. Because of inertia, the sensory areas of the inner ear cannot detect slight changes in the attitude of the airplane, nor can they accurately sense attitude changes that occur at a uniform rate over a period of time. On the other hand, false sensations are often generated; leading the pilot to believe the attitude of the airplane has changed when in fact, it has not. These false sensations result in the pilot experiencing spatial disorientation."

The Alameda County Sheriff's Office Coroner's Bureau, Oakland, California, performed an autopsy on the pilot. The cause of death was listed as blunt force trauma. The FAA's Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, performed toxicological testing; tests were negative for ethanol and all tested-for drugs. Carbon monoxide testing could not be performed with the samples available.