CEN15FA291

The pilot’s ostentatious low-altitude aerobatic display, which resulted in an aerodynamic stall/spin when he exceeded the airplane’s critical angle of attack. Contributing to the accident was the pilot’s impairment due to alcohol and drugs.

A witness reported seeing the airplane flying "right over the rooftop" of a home before turning along the shoreline at an altitude of 20-50 ft above the ground. He initially thought the airplane was going to land. The witness then observed the airplane climb straight up into a loop maneuver, roll inverted, then descend nose-first into the ground. Another witness said the airplane did 3-4 "wing waves" before it completed ½ of a loop, then descended straight down. A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The impact damage to the airplane was consistent with a stall/spin, which resulted from the airplane exceeding its critical angle of attack during the attempted loop. Toxicological testing revealed the presence of several impairing substances, including alcohol, opiod medication (hydrocodone), a benzodiazepine (alprazolam), as well as evidence of withdrawal from cocaine. The pilot was likely significantly impaired by the combination of these substances, and this level of impairment contributed to his poor decision-making, as well as his inability to safely operate the airplane.

The autopsy of the pilot was performed by the Medical Examiner, County of Nueces, Corpus Christi, Texas, on July 6, 2015. The cause of death was blunt head trauma and the manner of death was an accident. No significant natural disease was identified. Toxicology testing performed by AIT labs in Indianapolis, Indiana, at the request of the medical examiner identified alprazolam at 3.0 ng/ml, its metabolite, 7- aminoclonazepam at 12.2 ng/ml, benzoylecgonine at 116 ng/ml, hydrocodone at 18.7 ng/ml, and ethanol at 0.163 gm/dl in femoral blood. A Forensic Toxicology Fatal Accident Report was prepared by the FAA Civil Aerospace Medical Institute. No carbon monoxide was detected in the blood (heart). 153 (mg/dL, mg/hg) of ethanol was detected in the blood (femoral); 159 (mg/dL, mg/hg) of ethanol was detected in the urine; and 160 (mg/dL, mg/hg) of ethanol was detected in the vitreous. N-Propanol was detected in the urine. Anhydronecgonine methyl ester was not detected in the blood (heart), but it was detected in the urine. 0.133 (ug/ml, ug/g) of benzoylecgonine was detected in the blood (heart), and 2.9091(ug/ml, ug/g) of benzoylecgonine was detected in the urine. Dihydrocodeine was not detected in the blood (femoral), but 0.019 (ug/ml, ug/g) of dihydrocodeine was detected in the urine. Ecgonine methyl ester was detected in the urine and the blood (heart). 0.085 (ug/ml, ug/g) of hydrocodone was detected in the urine, and 0.021 (ug/ml, ug/g) of hydrocodone was detected in the blood (femoral). Hydromorphone was not detected in the blood (femoral), but 0.026 (ug/ml, ug/g) of hydromorphone was detected in the urine. The National Transportation Safety Board's (NTSB) Chief Medical Officer provided the following information concerning the toxicology results. (The NTSB Medical Factual Report is in the docket material associated with this accident report) Alprazolam is a benzodiazepine prescription medication available as a Schedule IV controlled substance. Benzodiazepines cause dose-related central nervous system depression varying from mild impairment to hypnosis. The usual therapeutic window for alprazolam is between 6 ng/ml and 20 ng/ml and it carries the following warning: The side effects of alprazolam are typical of benzodiazepines and include sedation, impaired coordination and muscle relaxation. Warnings - may impair mental and/or physical ability required for the performance of potentially hazardous tasks (e.g., driving, operating heavy machinery). Benzoylecgonine and ecgonine methyl ester are inactive metabolites of cocaine and anhydroecgonine methyl ester is a metabolite of cocaine that is only present after cocaine has been smoked. Cocaine is rapidly metabolized; its half-life is approximately 0.8 ± 0.2 hours, while the half- life of benzoylecgonine is 6 hours.3 Smoking cocaine acutely results in euphoria, excitation, feelings of well-being, general arousal, and increased sexual excitement; higher doses may result in psychosis, delusions, hallucinations, irritability, fear, paranoia, antisocial behavior, and aggressiveness. After the brief "high" wears off, users may exhibit dysphoria, depression, agitation, nervousness, drug craving, fatigue, and inability to sleep. Hydrocodone is an opioid analgesic available as a prescription medication and listed as a Schedule II controlled substance, most commonly in combination with acetaminophen (also known as Tylenol). It is commonly sold with the names Vicodin, Lortab, and Norco. Hydrocodone does not undergo significant post mortem redistribution and post mortem levels likely represent antemortem ones. Its usual therapeutic range is between 0.010 and 0.050 ug/ml and it carries this warning: Hydrocodone is more toxic than codeine, with a greater addiction liability. May impair mental and/or physical ability required for the performance of potentially hazardous tasks (e.g., driving, operating heavy machinery). Hydromorphone and dihydrocodeine are metabolites of hydrocodone and are both also active opioid analgesics. Ethanol is the type of alcohol present in beer, wine, and liquor. It is a social drug that acts as a central nervous system depressant. After ingestion, at low doses, it impairs judgment, psychomotor functioning, and vigilance; at higher doses ethanol can cause coma and death. Generally, the rapid distribution of ethanol throughout the body after ingestion leads to similar levels in different tissues. Federal Aviation Regulations, Section 91.17 (a) prohibits any person from acting or attempting to act as a crewmember of a civil aircraft while having 0.040 gm/dl or more alcohol in the blood. The effects of alcohol on aviators are generally well understood; alcohol significantly impairs pilots' performance, even at very low levels. The 1356 surface weather observation at the Corpus Christi Naval Air Station (NGP) located about 11 miles to the south the accident site was: wind 150 degrees at 18 knots gusting to 25 knots; 10 miles visibility; few clouds at 2,100 feet; scattered clouds at 4,000 feet; temperature 31 degrees C; dew point 26 degrees C; altimeter 29.99 inches of mercury. The 28-year-old pilot held a private pilot certificate with a single-engine land airplane rating. He held a second class airman medical certificate that was issued on July 18, 2014, with the restriction to wear corrective lenses. During his medical examination in July 2014, the pilot reported that his total flight time was 700 hours. The airplane impacted the terrain in a steep, nose down attitude. There was no post impact ground fire. The engine compartment, fuselage, wings, and empennage exhibited extensive crushing and buckling, but otherwise remained intact. The propeller and engine compartment were crushed up and aft from the impact. The wings remained attached to the fuselage. The right wing was broken and buckled forward about mid-span. The inboard leading edge of the right wing was found resting over the engine compartment. The outboard leading edge of the right wing impacted the edge of the tee box where the terrain dropped down about 3 feet. The left wing exhibited aft crushing along its outboard lower leading edge. The ailerons remained attached to the wings. The tail and empennage exhibited forward buckling. There was no impact damage to the horizontal and vertical stabilizers. Flight control cable continuity was confirmed from all flight control surfaces to their respective cockpit controls. The elevator trim continuity was confirmed from the elevator trim to the elevator trim control. Witnesses, who arrived at the accident site before the emergency first responders, reported that they saw fuel leaking from the wings and smelled fuel. Both wing fuel tanks were split open along the leading edge of the fuel tanks. The grass exhibited fuel blight when it was examined about 48 hours after the accident occurred. The examination of the Continental 95-horsepower engine revealed that it had power train continuity when the propeller was turned. Thumb compression and suction were observed on all four cyliders. The left and right magnetos fired on all four towers when the magneto shaft was rotated. The spark plugs exhibited a light gray color and the electrodes exhibited normal wear patterns. The carburetor was broken at the air intake attachment. The carburetor bowl did not contain fuel and the carburetor floats were intact. The examination of the two-bladed wooden Sensenich propeller revealed that one blade was fractured about mid-span. About six to ten inches of the remaining wooden blade was splintered opposite the direction of rotation. The other blade remained intact, but it was cracked along the length of the span. The leading edge of the blade had a metal cap installed and it exhibited chordwise scratching. The airplane was a tandem two-seat, single-engine Champion 7BCM, serial number 47-934. It was equipped with a 95-horsepower Continental C90-8F engine, serial number 15452-9-8R,