ERA13FA295

The pilot’s loss of airplane control during high-altitude maneuvering and his subsequent failure to recover airplane control. Contributing to the accident was the flight instructor’s inadequate supervision of the pilot and his failure to perform remedial action.

The purpose of the flight was for the pilot to accomplish a flight review with a flight instructor. According to air traffic control records, after takeoff, the pilot handling radio communications requested maneuvering airspace for airwork in an altitude block of 13,000 to 15,000 feet mean sea level (msl). About 8 minutes later, the air traffic controller asked the pilot to state his heading, but he did not respond. A review of recorded radar data revealed that, about 14,000 msl and 3 miles southeast of the accident site, the airplane made two constant-altitude 360-degree turns and then proceeded on a north-northeasterly heading for about 2.5 miles. The airplane then abruptly turned right and lost altitude, which is consistent with a loss of airplane control. The airplane continued to rapidly descend until it impacted trees and terrain on a southerly heading. No discernible distress calls were noted. The wreckage was found generally fragmented, and all of the airplane's structural components and flight control surfaces were accounted for within the wreckage debris path. Subsequent examination of the engines revealed evidence of rotation and operation at impact and no mechanical malfunctions or failures that would have precluded normal operation.

Enhanced Ground Proximity Warning System The airplane was equipped with a Honeywell Enhanced Ground Proximity Warning System (EGPWS). The outer case sustained minor damage; however, the internal memory survived the impact. The unit was sent to Honeywell for download of the data under the direction of a NTSB air safety investigator. Although the unit captured the final portion of the accident flight, the data, according to the manufacturer, was not accurate. The position data was observed in the "dead reckoning" mode, indicating that the GPS data was invalid or went out of navigation mode. This resulted in significant inaccuracies in the aircraft position data toward the end of the recording. Engines The engines were examined at the Honeywell facilities at Phoenix, Arizona on September 16 through 18, 2013, under the direction of the NTSB IIC. The teardown and examination of the left engine, S/N P-79794C, revealed that the type and degree of damage was indicative of an engine that was rotating and operating at the time of impact. Numerous indicators of rotation and operation were noted, including rotational scoring, ingested and burned organic debris, and metal spray adhesion. No pre-existing condition was found that would have prevented normal operation. The teardown and examination of the right engine, S/N P-79792C, revealed that the type and degree of damage was indicative of an engine that was rotating and operating at the time of impact. Numerous indicators of rotation and operation were noted, including rotational scoring, ingested and burned organic debris, and metal spray adhesion. No pre-existing condition was found that would have prevented normal operation. For additional information regarding the examination of the engines, refer to the Honeywell Engine Examination Reports, located in the public docket for this accident. Pilot A postmortem examination of the pilot was performed at the Medical University of South Carolina, Charleston, South Carolina on June 21, 2013. The autopsy report noted the cause of death as "Full body blunt trauma due to General aviation collision with ejection" and the manner of death was "Accident.". Forensic toxicology testing was performed on specimens of the pilot by the Federal Aviation Administration (FAA) Bioaeronautical Sciences Research Laboratory (CAMI), Oklahoma City, Oklahoma. The CAMI toxicology report indicated negative for carbon monoxide, ethanol, and drugs. Testing for cyanide was not performed. Flight Instructor A postmortem examination of the flight instructor was performed at the Medical University of South Carolina, Charleston, South Carolina on June 22, 2013. The autopsy report noted the cause of death as "Full body blunt force trauma" and the manner of death was "Accident.". Forensic toxicology testing was performed on specimens of the flight instructor by the Federal Aviation Administration (FAA) Bioaeronautical Sciences Research Laboratory (CAMI), Oklahoma City, Oklahoma. The CAMI toxicology report indicated negative for ethanol. Testing for carbon monoxide and cyanide was not performed. The report indicated that there was diphenhydramine in the liver and urine, pioglitazone in the liver and urine, and 47.3 ug/ml salicylate in the urine. Diphenhydramine (Benadryl® or Sominex®) is an over-the-counter sedating antihistamine used to treat allergies and Sominex® is marketed as a non-prescription sleep aid. A determination of possible impairment was not possible since there was no blood available for testing. Pioglitazone (Actos®) is a prescription oral antidiabetic agent that acts primarily by increasing uptake of glucose by peripheral organs and decreasing glucose production by the liver. It is used in the management of type 2 diabetes mellitus. According to CAMI, the flight instructor had diabetes that was treated and controlled with oral medications and was issued a Class 1, Restricted Medical Certificate, not valid for any class after May 31, 2014. He had also lost an eye due to an injury years ago; however, he was evaluated at 20/20 visual acuity in his remaining eye during his most recent FAA medical examination. Salicylate is a metabolite of aspirin, an over-the-counter anti-inflammatory medication to treat aches and pains, as an antipyretic to reduce fever. The report also noted 127 mg/dl glucose in the urine. Postmortem urine levels above 100 mg/dL are considered abnormal. No blood was available for hemoglobin A1C analysis. The accident site was situated on level ground on the grounds of the Francis Marion National Forest. The first point of impact was trees, then the ground. The accident site consisted of a swamp. The coordinates of the first observed impact with trees were 33.06239N, 079.52365W. The coordinates of the main wreckage (cockpit area) were 33.06193N, 079.52374W. The total length of the wreckage path was about 290 feet in length and 40 feet in width. The magnetic heading from initial tree impact to the cockpit was about 190 degrees. Measurements of the path through the trees was consistent with the airplane in a right bank of about 42 degrees and a descent angle of about 21 degrees. The wreckage was generally fragmented. There was no fire. All aircraft fuel tanks were breached during the impact sequence. There was a strong odor of jet fuel prevalent throughout the wreckage path. The left engine was separated from the airframe during the impact sequence and was found adjacent to the cockpit area. The right engine was located attached to the right, inboard wing section that was separated from the main wreckage and crushed against trees during the initial impact sequence. Several smoothly-cut tree branches were found at the area of initial tree impact. The disbursement of the branches was consistent with contact by both engine propellers. The wreckage was recovered to a storage facility at Griffin, Georgia, where a detailed examination of the wreckage was performed. All major structural components of the airframe, including all flight control surfaces, were accounted for. Flight control cable continuity could not be completely established due to the general fragmentation of the wreckage. Cable ends that were identified exhibited overstress indications or were torn from their attachment points. The landing gear selector handle was found in the up, or retracted, position. The physical position of the landing gear could not be determined due to impact damage. The position of the flaps at the time of the accident could not be determined due to impact damage. An external examination of the engines was performed during the wreckage review. No evidence of uncontained failure or in-flight fire was observed. The engines were shipped to the manufacturer's facility in Phoenix, Arizona, for a teardown examination under the direction of the NTSB Investigator-in-Charge (IIC). The propeller assemblies were examined during the wreckage review. Both propellers had similar damage. Each one had the cylinder/piston fractured off. Both propellers were missing their spinners. The left propeller was still attached to the gearbox; however, the gearbox was separated from the engine due to a fractured engine shaft. The propeller experienced damage due to impact and a power setting or blade angle could not be established; however, slight curved tips and some rotational scoring was noted on the blades. The right propeller was still attached to the gearbox; however, the gearbox had separated from the engine due to a fractured engine shaft. The "R3" blade was fractured off the clamp assembly. All three blades had slight twisting signatures. No anomalies were noted with either propeller assembly that would have precluded normal operation. For additional information regarding the examination of the propellers, refer to the Hartzell Propeller Examination Reports, located in the public docket for this accident. The airplane wa