Aviation Accident Summaries

Aviation Accident Summary WPR11FA145

Phoenix, AZ, USA

Aircraft #1

N910PA

PIPER PA-28-181

Analysis

The airplane struck a rock outcropping near the peak of a 4,600-foot mountain during a night training flight that included very-high frequency omnidirectional radio range and GPS tracking and intercepting maneuvers in visual meteorological conditions. The airplane had a flight instructor and two pilot-rated students onboard. It could not be determined who was flying the airplane at the time of the accident. According to the operator, the flight instructor had been counseled not to fly in that particular area at night because it was dark with no ambient surface light to illuminate the area. The flight school had other approved areas designated for night training flights. It is likely that the pilots were practicing a tracking or intercepting maneuver while not adequately monitoring the environment, which lacked illumination, to maintain sufficient altitude as they approached mountainous terrain. The damage to the airplane and associated ground scars were consistent with the airplane flying in a straight-and-level attitude before impacting the rock outcropping. Postaccident examination of the airplane and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

Factual Information

HISTORY OF FLIGHT On February 25, 2011, about 2005 mountain standard time, a Piper PA-28-181, N910PA, impacted mountainous terrain about 20 miles northeast of Deer Valley Airport (DVT), Phoenix, Arizona. Bird Acquisition LLC., d.b.a. TransPac Aviation Academy, operated the airplane under the provisions of 14 Code of Federal Regulations Part 141, as an instructional flight. The certified flight instructor (CFI) and two students were fatally injured. The airplane was substantially damaged during the impact sequence and subsequent post impact fire. Night visual meteorological conditions prevailed for the night instrument training flight. A company flight plan had been filed for the night flight that had departed DVT about 1907. The flight was scheduled to return to DVT about 2230. According to the operator, the flight was dispatched at 1847 with a CFI and two students to conduct a training flight. The accident flight was the ninth lesson out of 40 lessons in the instrument rating, Chinese Ab-initio Course syllabus, and was an introduction to VOR (very high frequency omnidirectional range) and GPS (global positioning system) tracking and intercepting. The airplane was refueled by Cutter Aviation with an addition of 34 gallons 100-low lead aviation fuel, as requested by the CFI, at 1900. The airplane departed shortly thereafter. At 2230, the operator expected that the airplane would be back at their facility. At 2300, a late alarm sounded notifying the operators' dispatchers of the overdue airplane. At that point, the operator's emergency response plan was initiated, which included notifying the sheriff's department, DPS (Department of Public Safety), ARTCC (Air Route Traffic Control Center), FSS (Flight Service Station), TRACON (Terminal Radar Approach Control), and CAP (Civil Air Patrol). The following morning, search and rescue crews located airplane wreckage north of Carefree, Arizona, near the summit of Bronco Peak. There were no known witnesses to the accident. PERSONNEL INFORMATION The 23-year-old CFI seated in the right front seat, had been hired by TransPac Aviation Academy on September 27, 2010. The CFI's logbook was not made available to the investigation team. The aeronautical experience listed in this report was obtained from her employment application with the flight school, as well as the flight school's "person pilot log." According to flight records, from the time period of September 27, 2010, until February 25, 2011, the CFI had accrued 288.9 hours of flight time in the accident make and model airplane. For the month of February 2011, she had accrued 65.8 hours. The CFI held a first-class medical with no limitations, issued on February 5, 2008. Prior to her CFI position at TransPac Aviation Academy, the CFI had instructed at Alliance Flight Schools in Scottsdale, Arizona. The 21-year-old private pilot seated in the left front seat received his private pilot certificate with rating for airplane single engine land on February 17, 2011. A review of his flight log from the flight school showed a total time of 97.2 total hours, and in the make/model of the accident airplane. He held a third-class medical issued on September 22, 2010, with no limitations. The pilot had been enrolled at the flight school since September 20, 2010; the FAA approved program he was enrolled under was identified as the Chinese Ab-Initio Program. METEOROLOGICAL INFORMATION Reported Aviation Routine Weather Report (METAR) for DVT at 1853 reported calm wind; clear skies; visibility 10 miles; temperature was 14 degrees Celsius; dew point was minus 01 degrees Celsius; altimeter setting was 29.90 inches of Mercury. Sunset for the day of the accident as calculated by the United Sates Observatory Astronomical Applications Department was determined to be 1822, which was followed by the end of civil twilight at 1847. The phase of the moon for that day was a waning crescent with 41-percent of the moon's visible disk illuminated. According to the Federal Aviation Administration (FAA), the definition of night flight is the period between 1 hour after sunset and 1 hour before sunrise. AIRCRAFT INFORMATION The airplane was a 1999 Piper PA-28-181, serial number 2843300. The airplane had a progressive inspection Event 2 performed on February 15, 2011. The recorded airplane total time was 13,646.3 hours; engine total time was 8,484.3 hours and propeller total time was 212.4 hours. According to the flight school, from February 15 to the date of the accident the airplane had flown a total of 26.3 hours; airframe total time was 13,672.6 hours, engine total time was 8,510.6 hours, and propeller had 238.7 hours, time since new. A Lycoming normally aspirated O-360-A4M engine, serial number L-27382-26A, powered the accident airplane. The recorded engine total time at the last condition inspection was 8,510.6 hours since new, with 238.7 hours flown since overhaul. WRECKAGE AND IMPACT INFORMATION The accident site was located in the Tonto National Forest, identified as Bronco Peak, at an elevation of 4,600 feet. The wreckage came to rest on a 10-degree slope with the debris path oriented along a magnetic heading of 020 degrees. The first identified point of impact (FIPC) was on the north-facing side of the Bronco Peak summit, which consisted of pieces of the left wing, and was about 900 feet south of the main wreckage. On the north face was a vertical rock outcropping that was oriented along a north and south heading. A section of the left wing with the aileron attached, was located about halfway down the rock outcropping. The height of the rock outcropping was estimated to be about 15 feet in height. At the top of the rock outcropping were paint chips, as well as aluminum transfer. An inspection of this section of wing revealed that the bell crank remained in the wing along with the attached aileron cables; the cables had separated and exhibited overload signatures. About 20 feet upslope of the outboard left wing was the left wing center section. Both of these pieces were located on the southeast side of the rock outcropping. On the northwest side of the rock outcropping, about 50 feet upslope from the FIPC, the left inboard wing section with flap and fuel tank was located with the fuel cap, which remained secured in its normal location. Approximately 30 feet upslope of the left inboard wing section was the left main landing gear. No debris from the left landing gear was located at the top of the saddle. Another debris field was identified on the south side of the summit approximately 750 feet away from the FIPC. This area consisted of shards of Plexiglas, as well as desert vegetation with pulled up roots. The main wreckage came to rest about 150 feet downslope of the second debris path; there were no other major components from the FIPC's debris path to the second debris path. The main wreckage consisted of the fuselage, empennage and tail section, and the engine. The fuselage section was inverted and mostly consumed by the post-crash fire. The empennage section exhibited fire damage. The tail section came to rest inverted, and all flight control surfaces remained attached. Due to terrain and environmental conditions, partial control continuity was verified from the tail to cabin area. All major flight control surfaces were identified on-scene. In the cabin area (forward cockpit controls), both horizontal stabilator cables remained attached to the T-bar assembly; however, the T-bar assembly was not attached to any structure in the forward cockpit area. The left rudder cable remained attached to the rudder pedal bar by its link. The link remained attached to the rudder tube. During the on-site investigation the right rudder cable and the aileron cables or chains were not located. At the tail section both rudder cables remained attached to the rudder horn. The trim drum assembly was displaced from the tail cone section due to fire damage. Five exposed threads on the top of the trim drum jack screw were measured, which correlated to a neutral trim position. All tail section control surfaces were present, but fire damaged. The right wing with landing gear separated from the fuselage and came to rest about 25 feet upslope of the main wreckage. The wing was complete with control surfaces attached; there was no evidence of fire noted on the wing. The engine came to rest inverted facing downhill on a 020-degree heading, which was in line with the airplane's direction of travel when it struck the rock outcropping at the FIPC. It remained attached to the firewall by wires and cables. The propeller remained attached via the propeller assembly and crankshaft. There were no obvious holes in the crankcase, but a crack in the crankcase in between the Nos. 2 and 4 cylinders was noted. The accessory section sustained thermal damage. Once at the staging area the left wing was laid out in its entirety for further examination, as it had been fragmented into several pieces at the accident site. At the wing tip section leading to trailing edge accordion crush damage was observed. The crush damage angle was consistent with straight-and-level flight. Radar Data Radar data obtained from the Phoenix Terminal Radar Approach Control (TRACON) facility, identified the accident airplane departing DVT and proceeding toward the Carefree Sky Ranch Airport (18AZ) passing over the airport at 5,000 feet at 1943. The radar target continued on a north-northeast heading following Victor 327 airway and climbing to 6,100 feet. At 1951, the radar target turned back to follow Victor 327 toward Phoenix at 6,000 feet. At 1958, the radar target passed over the east side of 18AZ along Victor 327 at 5,000 feet. At 2000, the radar target was positioned southeast of 18AZ at 4,500 feet, it then showed a 180-degree left turn to a northwest heading, followed by a turn to the north, and maintained altitude at 4,500 feet. At 2004, the radar target was at 4,500 feet on a north-northeast heading west of Victor 327 and North of 18AZ. At 2004:30, the radar track stops moving, with no further movement observed until the track ends at 2004:58. MEDICAL AND PATHOLOGICAL INFORMATION The Maricopa County Coroner, Phoenix, completed autopsies for the certified flight instructor (CFI), and two private pilots; all three autopsies were completed on March 1, 2011. The cause of death listed for all three pilots was blunt impact injuries. The FAA's Civil Aerospace Medical Institute performed forensic toxicology on specimens from all three pilots. Right seat - CFI toxicology findings Analysis of the specimens contained no findings of carbon monoxide, ethanol, or tested drugs. The report contained the following findings for cyanide: 3.11 (ug/ml) cyanide detected in blood. Left seat - Private pilot toxicology findings Analysis of the specimens for the pilot contained no findings for carbon monoxide, cyanide, volatiles or tested drugs. TESTS AND RESEARCH Flight control continuity was established throughout all the primary flight control surfaces (aileron, flaps, stabilator, and rudder). At the forward cockpit controls the primary aileron cables were attached to either end of the chain assembly. The chain was engaged with the T-bar sprocket (center). The horizontal portion of the T-bar section with associated sprockets separated in two pieces from the vertical section. Located within the forward cockpit section, the right rudder cable with the link was still attached to the cable, but the link separated from the rudder tube assembly at the weld. From the primary cables to the aileron, the left cables were still attached to the bell crank (at site). During the wreckage reconstruction the primary and balance cables remained attached to bell crank. The cables were broomstrawed at the separation points. Aileron control continuity was established. The horizontal stabilator cables remained attached to the stabilator tube assembly. The fuel selector valve was not located. The ELT was found, but thermally destroyed, with no make and model data available. The instrument panel was destroyed. The airspeed indicator remained in the instrument panel and indicated 55 knots. The horizontal situation indicator (HSI) was manufactured by Garmin, and the information is displayed digitally; due to damage to the unit, the frequency was not determined. The card was set at 175 degrees, with the horizontal needle full scale UP. The vertical needle was deflected left in between the center and first hash mark. Both flags were visible. The vertical speed indicator face separated from the case. No needle was present, and no marks on the face were visible. The directional gyro, was manufactured by Sigmatek, remained intact, and displayed a heading of 130 degrees. No heading bug was visible. The card setting shaft was bent to the right. There was no knob. The Artificial Horizon exhibited extensive impact damage, with the glass and case partially broken, and was not readable. Engine Manual rotation of the engine via the crankshaft and propeller assembly produced mechanical and valve train continuity; thumb compression was also obtained in all cylinders. The spark plugs appeared normal according to the Champion aviation check-a-plug chart AV-27. The oil pick up screen was free of debris. The carburetor inlet screen was also free of debris. Both magnetos sustained fire damage and did not rotate; but remained attached at their respective mounting pads. The fuel pump had been mostly consumed by fire. The vacuum pump was displaced and broken open; the rotor remained intact. It also sustained fire damage and melted. Propeller The propeller was a Sensenich model 76EM8S14-0-62, serial number 64765. Total time since the last condition inspection was 238.7 hours since new. Both blades exhibited some leading and trailing edge damage. One blade was bent at the tip. The other blade was corkscrewed and bent aft with red transfer on the face of the blade. The propeller remained connected to the engine via the propeller assembly. At the conclusion of the postaccident airframe and engine examinations, there was no evidence of a mechanical malfunction or failure that would have precluded normal operation. OTHER INFORMATION According to the operator, the CFI had been counseled not to fly in that particular area at night, as it was dark with no ambient surface light from the surrounding city to illuminate the area. There are other approved areas that the flight school has designated for night training flights. As a result of this accident, the operator revised and clarified their operating procedures for night flights, training areas, and minimum safe operating altitudes (identified as Minimum Authorized Altitudes (MAA's).) The area where the accident occurred, no maneuvers shall be done within 3 nautical miles of the Sky Ranch at Carefree Airport at any altitude. The MAA's were established only for night flights in the practice areas.

Probable Cause and Findings

The pilot and flight instructor's failure to adequately monitor the flight task and environment while maneuvering to maintain sufficient altitude with rising terrain in dark night conditions and the flight instructor's improper decision to practice in an area known to have no illumination, which led to collision with a rock outcropping.

 

Source: NTSB Aviation Accident Database

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