Aviation Accident Summaries

Aviation Accident Summary WPR09FA150

Pomona, CA, USA

Aircraft #1

N129AB

PIPER PA28-236

Analysis

The airplane departed the airport on an instrument-flight-rules clearance. The weather at the airport was 500-foot overcast, with a visibility of 1 mile. The overcast layer was solid up through 3,100 feet mean sea level (msl). The departure instructions were to climb on heading 150 to 1,400 feet msl, then initiate a climbing turn to heading 130, intersect the VOR 164 radial outbound until 9 miles south of the airport, and climb to 4,000 feet. Just after takeoff, at approximately 1,400 feet, the airplane made a climbing turn to 146 degrees and continued to climb on that course for about 1.5 minutes. At 2,500 feet, the airplane started a right-hand turn. The deviation of the airplane’s course prompted the terminal radar approach controller (TRACON) to ask if the pilot had canceled his clearance. The pilot responded in a steady even tone, “Negative, nine alpha bravo still climbing.” Five seconds later the airplane was no longer in radar contact. The radar track depicted the airplane in a climbing right-hand turn in a tightening spiral directly over the accident location. The aircraft wreckage was located on a hillside about 2 miles south of the departure airport and in the vicinity of the last radar return. A review of the pilot’s flight records revealed that he held an instrument rating issued in August 2006, and had logged just two instrument approaches since January 2007, neither within the last 90 days. Additionally, he had accumulated 0.8 hours of simulated instrument time and 0.8 hours of actual instrument time since January 2007. There is no record of the pilot obtaining an instrument proficiency check within the 12 months prior to the accident. The tone of the pilot’s response to TRACON’s radio query implied that he was not aware that the airplane had deviated from the departure clearance and was in a steadily tightening right-hand turn. This lack of awareness could be attributed to spatial disorientation or a distraction away from the primary flight instruments.

Factual Information

HISTORY OF FLIGHT On March 14, 2009, at 1115 Pacific daylight time, a Piper PA-28-236, N129AB, impacted elevated terrain in Pomona, California. The airplane was operated by the owner under Title 14 Code of Federal Regulations Part 91. The two private pilots on board were killed, and the airplane was destroyed. Instrument meteorological conditions (IMC) prevailed, and an instrument flight plan (IFR) had been filed. The flight originated at Brackett Field Airport, La Verne, California, about 1112, and its destination was Mojave, California. The accident site was 2.15 miles south of Brackett Field Airport. At 1147, Brackett Field METAR reported winds variable at 5 knots; 1-statute mile visibility in mist; and 500-foot overcast. The next closest airport was the Ontario Airport, which is located 10 miles east of Brackett Field reported at 1053, winds 150 degees at 4 knots; and visibility was 2.5-statute miles in mist, with an 800-foot overcast. A pilot who departed ahead of the accident aircraft stated that he encountered IMC conditions at 500 feet above ground level (agl) and was in solid IMC until on top of the cloud layer at 3,100 feet mean sea level (msl). Witnesses reported that before departure they observed the male pilot seated in the left seat and the female pilot seated in the right seat of the airplane. The pilot received his IFR clearance from Brackett ground control at 1046. The pilot was cleared to Paradise VORTAC via Brackett departure 26 (climb via heading 159 to 1,400 feet msl, then climbing left turn via heading 130, intersect the Pomona VOR 164 radial outbound to PRADO intersection), then follow V16 to the Paradise VORTAC. The Pomona VORTAC is situated to the left of the airplane's departure course, and PRADO intersection is 9 miles south of the airport. The pilot was to climb to VFR on-top conditions, if not on top by 4,000 feet, to maintain 4,000 feet and advise air traffic control (ATC). Radar data obtained from Southern California terminal radar approach control (TRACON) tracked the airplane from Brackett Field to the accident location. The first radar return was at 1,300 feet at 1112:16, over the west end of runway 26. The track makes a climbing left turn to a course of 146 degrees. At 1113:46, at 2,500 feet, the track starts a right-hand turn that climbs as it tightens into a spiral. At 1114:20, the track passes through 90 degrees of the right-hand turn, 2,600 feet, and the pilot acknowledges his instructions to climb to 4,000 feet, and if not on-top to advise the controller. Twenty seconds later, at 2,900 feet, the controller asks if the pilot had canceled (his clearance). The pilot responded in a steady even tone, “Negative, nine alpha bravo still climbing.” At this point the track had turned 180 degrees, and was at 2,700 feet. This was the last communication from the pilot. Five second later, at 2,600 feet, the controller asks the pilot, “Ok, where are you going? Turn right heading 130…” The last radar return was at 1114:49, and 2,600 feet, directly over the accident location. PERSONNEL INFORMATION The pilot, age 52, held a private pilot certificate with ratings for airplane single-engine land and instrument airplane, issued on August 29, 2006. He held a third-class medical certificate issued on November 2, 2007, with no limitations. On his application for his instrument rating, dated August 29, 2006, he reported a total flight time of 190.9 hours. An electronic pilot logbook was obtained from the family; the first entry was dated January 20, 2007, and the last entry was dated February 28, 2009. Examination of the electronic logbook revealed total flight time during this period of time was 286.9 hours, 0.8 hours of actual instrument time, 0.8 hours of simulated instrument time, and 4 instrument approaches. The most recent instrument approach was dated October 29, 2008, flown in an SR-22. The next prior instrument approach was dated April 28, 2007, in the accident airplane. The pilot’s certified flight instructor (CFI) stated that he performed the pilot’s biennial flight review (BFR) on August 22, 2008. The flight review focused on visual flight rules (VFR) techniques and procedures; they did not fly any practice approaches or fly under simulated instrument conditions. The pilot’s total flight time was estimated to have been 478 hours. Federal Aviation Administration Regulation, Part 61.57 (c), states that no person may act as pilot-in-command under instrument flight rules (IFR) or in weather less than the minimum prescribed for visual flight rules (VFR), unless within the preceding 12 months that person has completed an instrument proficiency check, and within the preceding 6 calendar months, that person has logged at least 6 instrument approaches, holding procedures, and intercepting and tracking courses through the use of navigation systems. The second pilot, age 48, held a private pilot certificate, with a rating for single-engine land, issued on March 3, 2007. She held a third-class medical certificate issued on September 25, 2007, with the limitation of wearing glasses for near vision. She reported that her total pilot time was 180 hours on her medical application. On August 23, 2008, she started receiving instrument flight instruction from the same CFI that instructed the pilot. He stated that he had flown about 1.3 hours of actual instrument time, and 37 hours of simulated instrument time with her. AIRCRAFT INFORMATION The four-seat, low wing, fixed landing gear airplane, serial number (s/n) 28-7911303, was manufactured in 1979. It was powered by a Lycoming O-540-J3A5D, 235-hp engine, and equipped with a Hartzell constant speed propeller. Review of copies of the maintenance logbook records showed that an annual inspection was completed on March 6, 2009, at a recorded tachometer reading of 1125.3 hours, airframe total of 4,297.8 hours, and engine time since major overhaul (TSMOH) of 2,291.4 hours. Lycoming recommends 2,000 hours between overhauls. Damage to the Hobbs hour-meter and engine tachometer precluded the determination of current readings. A recent photograph of the airplane’s instrument panel was provided by the family. The instrument panel contained a single attitude gyro in front of the left seat and a directional gyro mounted below it. A vertical card compass was mounted on the center windscreen bow. Two course deviation (CDI) and glide slope indicators were also on the instrument panel. The com-nav suite consisted of two Garmin GNS-430’s positioned in the center of the instrument panel between the front seats. A Garmin GPSMap 496 was mounted to the left control yoke. Mounted in front of the right side instrument panel was a tablet computer, oriented slightly towards the left seat. WRECKAGE AND IMPACT The wreckage was located on a hillside at an elevation of 916 feet, on a 40-degree slope. The majority of the terrain was rock covered with dirt and grass. The hill is sparsely populated with scrub oak trees. There was a post impact fire that destroyed the cockpit remnants and center fuselage structure. The vertical stabilizer, horizontal stabilator, and left wing were located together. All control cable ends were attached to their control surface bell cranks. All separated control cable ends exhibited broomstrawed characteristics. A 5-foot outboard section of right wing was located 585 feet northeast of the main wreckage. The wing separation area had damage consistent with ground object impact. The engine had separated from its engine mount, the case was fractured, revealing the crankshaft, and missing three of the six cylinders and pistons. Both propeller blades had separated from the propeller hub and exhibited twisting along their longitudinal axis, and leading edge damage. The left wing and vertical stabilizer exhibited leading edge crushing aft along their entire length. Smaller aircraft debris were located downslope from the main wreckage. On April 3, 2009, the wreckage was examined by a Federal Aviation Administration (FAA) inspector and technical representatives from the airframe and engine manufacturer under the supervision of the Safety Board Investigator-in-Charge (IIC). The cockpit was completely destroyed; all instruments, tablet computer, and GPS components were fragmented. A SD card and a PCMCIA card were recovered and sent to the Safety Board Vehicle Recorder Laboratory. The PCMCIA card was too damaged to determine if any data could be recovered, and the SD card contained no recoverable data. The integrity of the instrument vacuum system could not be verified. Control cables were isolated and laid out. Control cable ends were observed connected to the aileron, stabilator, and rudder bell cranks. All cable separations had a broomstawed appearance, consistent with overload. The engine crank case was fragmented. The forward crankshaft bearing exhibited no signs of pitting or over temperature, no heat distress was observed on rotating engine components, and all exhaust elements had similar gray coloration. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy was performed on both pilots on March 20, 2009, by the Los Angeles County Coroner, Los Angeles, California. Both autopsy report findings stated the cause of death of each pilot was ascribed to "multiple blunt force injuries." The condition of the victims prevented the coroner from obtaining blood samples for toxicology testing. Forensic toxicology was performed on tissue specimens from the male pilot by the FAA Forensic Toxicology Research Team, Oklahoma City, Oklahoma. The toxicology report stated that the carbon monoxide test was not performed, the cyanide test was not performed, and results for volatiles included less than 13 mg/dl of ethanol detected in muscle. The results of the analysis were negative for all tested drugs. ADDITIONAL INFORMATION Spatial Disorientation The Instrument Flying Handbook (FAA-H-083-15A) defines spatial disorientation as " the lack of orientation with regard to position in space and to other objects." "A pilot in a prolonged coordinated, constant rate turn, will have the illusion of not turning. During the recovery to level flight, the pilot will experience the sensation of turning in the opposite direction. The disoriented pilot may return the aircraft to its original turn. Because an aircraft tends to lose altitude in turns unless the pilot compensates for the loss in lift, the pilot may notice a loss of altitude. The absence of any sensation of turning creates the illusion of being in a level descent. The pilot may pull back on the controls in an attempt to climb or stop the descent. This action tightens the spiral and increases the loss of altitude; hence, this illusion is referred to as a graveyard spiral. At some point, this could lead to a loss of control by the pilot." (FAA-H-083-15A)

Probable Cause and Findings

The pilot's spatial disorientation while flying in instrument meteorological conditions that resulted in a loss of control of the airplane. Contributing to the accident was the pilot's lack of recent instrument flying experience.

 

Source: NTSB Aviation Accident Database

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