NTSB Factual Report

HISTORY OF FLIGHT

On December 26, 2013, about 0530 eastern standard time, a Piper PA-30, N8372Y, was destroyed following an inflight break up, and impact with terrain near Biglerville, Pennsylvania. Night visual meteorological conditions prevailed and no flight plan was filed for the flight. The certificated private pilot and passenger were fatally injured. The personal flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. The flight originated from Bloomsburg Municipal Airport (N13), Bloomsburg, Pennsylvania, around 0445, with an intended destination of Summerville Airport (DYB), Summerville, South Carolina.

According to witnesses, the airplane was flying "low" and the engine noise was "loud." One witness reported that he heard the engine "miss" once, then the engine "revved up," and a few seconds later he heard the sound of impact. Another witness stated that when he heard the engine "spike."Radar tracking data that was obtained from the Federal Aviation Administration (FAA) Harrisburg Approach Control Radar facility located in Harrisburg, Pennsylvania. The radar data indicated that, the airplane was flying on a southwesterly heading at an altitude around 10,000 feet mean sea level (msl). Then around 0525, the airplane descended to 7,400 feet msl. At 0527 the airplane entered a left turn and descended. A few seconds later the radar target completed a 180 degree turn and the data indicated a 2,000 foot per minute descent and a 7.5 degrees per second turn rate. The last radar data, located in/near the accident location indicated that the airplanewas at 2,700 feet msl and a recorded ground speed of 179 knots.

PERSONNEL INFORMATION

According to FAA records, the pilot held a private pilot certificate with ratings for airplane single-engine land and multiengine land, and a third-class medical certificate issued on October 31, 2013, which included a restriction of "must wear corrective lenses for near and distant vision."

The pilot's logbook was recovered from the accident site and it listed a total of 196.1 hours of flight time. It also indicated that the pilot recorded a total of 12.3 hours of flight time at night, 1.2 hours of flight in actual instrument conditions, and 3.8 hours of flight time in simulated instrument conditions. In addition, there were 4.5 hours of flight time is the past 12 months, of which 4 hours occurred between December 20, 2013, and December 25, 2013.

AIRCRAFT INFORMATION

According to FAA records, the airplane was issued an airworthiness certificate in 1967 and was registered to the pilot on June 18, 2012. It was equipped with two Lycoming IO-320-series, 160- horsepower engines. It was also equipped with two 2-bladed Hartzell controllable pitch propellers. At the time of this writing, the maintenance logbooks had not been located. However, a receipt for maintenance performed on the airplane included an annual inspection that was dated November 18, 2014.

METEOROLOGICAL INFORMATION

An observation site from a National Weather Service source for Fountain Dale (RYT), Hamiltonban, Pennsylvania, located approximately 15 miles southwest of the accident site, at the time of the accident, showed rapidly changing conditions during the period with a band of snow moving across the region.

The RYT weather observation at 0453 indicated wind from 220 degrees at 3 knots, visibility 10 miles, ceiling overcast clouds at 7,000 feet above ground level (agl), temperature minus 4 degrees C, dew point minus 8 degrees C, and an altimeter setting 30.22 inches of mercury.

The RYT weather observation at 0553 indicated wind calm, visibility 10 miles, ceiling overcast at 3,200 feet agl, temperature minus4 degrees C, dew point minus 9 degrees C, and an altimeter setting of 30.21 inches of mercury.

The RYT weather observation at 0608 indicated calm wind, visibility 3 miles in light snow, ceiling broken at 2,800 feet, overcast at 7,000 feet, temperature minus 4 degrees C, dew point minus 8 degrees C, and an altimeter setting of 30.20 inches of mercury. In addition, the remarks section stated that snow began at 0556.

According to the Astronomical Applications Department at the United States Naval Observatory, the official moonset was at 1224, the official beginning of civil twilight was at 0659, and official sunrise was at 0729. The phase of the moon on the day of the accident was waning crescent, with 38 percent of the moon's visible disk illuminated.

A search of Flight Service Station records revealed that the pilot requested weather information and Notice to Airman (NOTAMs) on the day of the accident for Williamsport Regional Airport (IPT), Williamsport, Pennsylvania, and Farmville Regional Airport (FVX), Farmville, Virginia. The pilot did not file a flight plan and did not receive any other services for the accident flight.

The weather reported at IPT, which was approximately 27 miles northwest of the departure airport, around the departure time, indicated wind from 090 at 8 knots, visibility 1 ¾ statute mile, light snow, clouds overcast at 2,600 feet agl, temperature minus 4 degrees C, dewpoint minus 7 degrees C.

WRECKAGE AND IMPACT INFORMATION

The airplane impacted the ground and came to rest inverted. The wreckage path was oriented on a 179 degree heading and the debris path began about 2,350 feet prior to where the main wreckage came to rest. The main wreckage was oriented on about a 180 degree heading. Several pieces of airframe skin were located in the field leading up to the main wreckage. The first piece of airframe skin was located approximately 2,350 feet prior to the main wreckage. First responders reported an odor similar to 100LL in the field where the main wreckage was located.

The nose landing gear was located in the vicinity of and was separated from, the main wreckage.

The left and right engines were separated from the main wreckage, embedded in the field, and located approximately 10 feet from the main wreckage. When they were removed from the ground, fuel and oil were present in the craters.

One propeller blade was located in the field approximately 400 feet from the main wreckage and its associated propeller hub was located in the field approximately 500 feet from the main wreckage . The other propeller blade was not located. The second propeller was located about 50 feet aft of the main wreckage. Both blades remained attached to the propeller hub and flange. Both spinners were separated from the engines and located in the field along the debris path.

The outboard 6 foot of the right wing was located along the debris path about 600 feet from the main wreckage in the field. The inboard approximate 10 feet remained attached to the fuselage and exhibited crush damage. The right wing tip, was separated and located approximately 50 feet from the outboard section of the right wing. The right aileron remained attached to the right outboard section of the wing through one attach point. The right flap remained attached to the right wing through all attach points. The right wing fuel cap remained intact and seated, however that section was separated from the right wing. The right main landing gear remained attached to the right wing in the retracted position.

The aft section of the fuselage was separated at the aft pressure bulkhead. The rudder, vertical stabilizer, and inboard section of the left stabilator was located about 200 feet from the main wreckage. The right section of the stabilator was located approximately 675 feet from the main wreckage in an area of trees. The forward section of the left stabilator remained attached to the empennage. The main spar of the stabilator remained attached to the aft bulkhead. The rudder remained attached to the vertical stabilizer through all attach points and exhibited impact damage.

The outboard approximate 6 foot of the left wing was found separated from the fuselage and located in a field about 600 feet from the main wreckage. The left aileron was located in the field approximately 200 feet from the left outboard section of the wing. The inboard approximate 10 feet of the left wing remained attached to the fuselage and exhibited crush and impact damage. The forward section of the left wing was separated from the left wing spar and located approximately 10 feet forward of the main spar. The left inboard section of the flap remained attached to the inboard section of the wing through the outboard attach point. Aileron control cable continuity was confirmed from the base of the control column to the associated fracture points out to the aileron attach point. The aileron cable exhibited tensile overload at all fracture points. The main landing gear remained in the up and in the retracted position.

The cockpit exhibited extensive crush damage and was separated from the fuselage. The engine controls were intact. The throttle levers and propeller levers were in the midrange position. Flight control continuity was confirmed from the cockpit to all flight control surfaces through the respective tensile overload breaks. The air driven attitude indicator was disassembled and the gyro and gyro housing exhibited rotational scoring, consistent with operating at the time of impact. The electric turn and bank indicator was disassembled and the internal gyro and housing exhibited rotational scoring, consistent with operating at the time of impact.

The fuselage came to rest inverted in a corn field and it exhibited extensive impact damage The inboard section of the main wing spar remained attached to the fuselage. All seats were separated from the fuselage. The fuel selector valves were located in the fuselage and were disassembled. Both fuel selectors contained a fluid that tested positive for water using the water detecting paste.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy was performed on the pilot on December 27, 2013, by Forensic Pathology Associates, Allentown, Pennsylvania. The autopsy findings included the cause of death as "multiple injuries."

Forensic toxicology was performed on specimens from the pilot by the FAA Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma. The toxicology report stated no ethanol or drugs were detected in the liver.

TESTS AND RESEARCH

Engine Examinations

Both engines were examined at Anglin Aircraft Recovery in Clayton, Delaware. They were removed from storage and placed on pallets prior to the investigation team arrival. Upon arrival, the team determined which engine was the left and the right. The examination revealed that there were no mechanical malfunctions or abnormalities that would have precluded normal operation with either engine.

A detailed engine examination report for each engine are available in the official docket of this investigation.

Electronic Devices

A Garmin GPSMAP 696, an iPhone, a Motorola Droid X, and an iPad were found in the main wreckage area, retained, and sent to the National Transportation Safety Board Recorders laboratory for data download. Data was unable to be extracted from the iPhone nor the Motorola Droid X due to impact damage.

The Garmin GPSMAP 696 contained data that was recorded at the time of the accident flight. The data began at 0439 and continued until 0528. The last recorded data points indicated that the airplane was on a direct course to DYB, made a slight right turn approximately 45 degrees away from the track toward DYB at 0524. Then, it made a turn back to the left approximately 90 degrees, to the right approximately 90 degrees, and finally, it banked to the left and continued the bank and began a descent until the data points ended. The last data point recorded a ground speed of 141 knots.

ADDITIONAL INFORMATION

Spatial Disorientation

According to the FAA Airplane Flying Handbook (FAA-H-8083-3), "Night flying is very different from day flying and demands more attention of the pilot. The most noticeable difference is the limited availability of outside visual references. Therefore, flight instruments should be used to a greater degree.… Generally, at night it is difficult to see clouds and restrictions to visibility, particularly on dark nights or under overcast. The pilot flying under VFR must exercise caution to avoid flying into clouds or a layer of fog." The handbook described some hazards associated with flying in airplanes under VFR when visual references, such as the ground or horizon, are obscured. "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."

According to the FAA Instrument Flying Handbook (FAA-H-8083-15), a rapid acceleration "...stimulates the otolith organs in the same way as tilting the head backwards. This action creates the somatogravic illusion of being in a nose-up attitude, especially in situations without good visual references. The disoriented pilot may push the aircraft into a nose-low

or dive attitude."

The FAA publication Medical Facts for Pilots (AM-400-03/1), described several vestibular illusions associated with the operation of aircraft in low visibility conditions. Somatogyral illusions, those involving the semicircular canals of the vestibular system, were generally placed into one of four categories, one of which was the "graveyard spiral." According to the text, the graveyard spiral, "…is associated with a return to level flight following an intentional or unintentional prolonged bank turn. For example, a pilot who enters a banking turn to the left will initially have a sensation of a turn in the same direction. If the left turn continues (~20 seconds or more), the pilot will experience the sensation that the airplane is no longer turning to the left. At this point, if the pilot attempts to level the wings this action will produce a sensation that the airplane is turning and banking in the opposite direction (to the right). If the pilot believes the illusion of a right turn (which can be very compelling), he/she will reenter the original left turn in an attempt to counteract the sensation of a right turn. Unfortunately, while this is happening, the airplane is still turning to the left and losing latitude.

Pulling the control yoke/stick and applying power while turning would not be a good idea–because it would only make the left turn tighter. If the pilot fails to recognize the illusion and does not level the wings, the airplane will continue turning left and losing altitude until it impacts the ground."

NTSB Probable Cause

The noninstrument-rated pilot's spatial disorientation after inadvertently encountering instrument meteorological conditions at night and his subsequent loss of airplane control.