Aviation Accident Summaries

Aviation Accident Summary FTW00FA053

MCALESTER, OK, USA

Aircraft #1

N5697N

Mooney M20K

Analysis

The airplane impacted heavily wooded and rocky terrain during an uncontrolled descent from cruise climb in night visual meteorological conditions. Toxicological tests were positive for tramadol at therapeutic concentrations, and phenobarbital, nordiazepam, chlorepheniramine, pseudoephedrine, and phenylpropanolamine. The pilot had a history of substance abuse. It is reasonable to conclude that the pilot was impaired by the use of or withdrawal from the effects of such medications at the time of the accident. The airplane's left wing speed brake was found in the stowed position, and the right wing speed brake was found deployed. FAA verified that flight test results provided by the speed brake manufacturer indicated no significant effect on handling qualities with one speed brake deployed. No evidence of an in-flight fire was found at the accident site. No evidence of uncorrected discrepancies was found in the maintenance records. No evidence of an in-flight mechanical and/or flight control malfunction was found that would have rendered the airplane uncontrollable prior to the impact.

Factual Information

HISTORY OF FLIGHT On December 27, 1999, approximately 0610 central standard time, a Mooney M20K, N5697N, impacted trees and terrain east/southeast of the McAlester Regional Airport, near McAlester, Oklahoma. The airplane was registered to Airmed, Inc., of McAlester, Oklahoma and operated by the pilot under 14 Code of Federal Regulations (CFR) Part 91. Impact forces and fire destroyed the airplane. The private pilot, sole occupant, received fatal injuries. Night visual meteorological conditions prevailed for the planned cross-country flight, which originated from the McAlester Regional Airport, McAlester, Oklahoma, approximately 10 minutes prior to the accident. The flight's intended destination was Altus, Oklahoma, and a flight plan was not filed for the business flight. Local authorities, family members, acquaintances, and witnesses reported the following information to the NTSB investigator-in-charge (IIC). The pilot was a medical doctor (MD) and operated the McDaniel Medical Clinic, at McAlester, Oklahoma. He was also on the emergency room (ER) staff at the Jackson County Medical Hospital, Altus, Oklahoma, where he worked a 24-hour ER shift for 2 or 3 days per week. Following the ER duty, the pilot would rest before returning via his airplane to McAlester. On December 25, the pilot and his family flew on a round trip flight to Altus, Oklahoma. Following their arrival about midnight at McAlester, the pilot slept 7 to 8 hours. On December 26, 1999, the pilot was home with his family, and that night he slept 6 to 7 hours. The following morning, the pilot departed his residence approximately 0530 to go to the airport for the flight. Two deer hunters, driving through Watts Ranch, noticed a "red light and orange/yellow colored light weaving from left to right at a slow pace" approximately 1/2 to 1 mile height in the sky. Then the lights started to descend straight toward the ground. The lights disappeared near Jack Fork Mountain, the engine started "revving", and then there was a bright flash. The witnesses did not see any evidence of an in-flight fire. Another witness, from inside his residence, "heard the engine stalling and revving at least 3 times" at an altitude of 300 to 400 feet above the trees. This witness went outside his home, heard the impact and saw a "fireball." These witnesses reported the accident to local authorities. An air and ground search was initiated, and the aircraft was located later that morning at North 34.41.22 degrees; West 095.31.78 degrees along the northern ridge of Jack Fork Mountain in heavily wooded and rocky terrain. PERSONNEL INFORMATION The 46-year-old pilot held an FAA third class medical certificate, issued January 29, 1999, with no restrictions. Pilot records indicated that he had accumulated a total flight time of 2,239.8 hours as of July 1998. The pilot's logbook indicated that he flew the accident aircraft 341.5 hours in 1998, with the majority of his flights being between McAlester and Altus, Oklahoma. The NTSB IIC was informed that the pilot's current logbook would have been in the airplane. The logbook was not located and is presumed destroyed. AIRCRAFT INFORMATION N5697N, a Mooney M20K, serial number 25-0777, was issued an airworthiness certificate on October 7, 1983. Registration to the current owner/pilot was dated July 21, 1995. The airplane was equipped with the Rocket Conversion which included the Continental TSIO-520-NR reciprocating engine, serial number 290729R, rated at 305 horsepower with a McCauley model 3AF32C505-C, 3-bladed propeller, serial number 941669, installed. The airplane was equipped with an EGT-701 engine monitor, long range fuel tanks, and a fuel totalizer [FT-101] management system. Precision Flight, Inc., speed brakes and standby vacuum system were installed. On April 3, 1999, the last annual inspection was performed at an accumulated airframe time of 2,243.3 hours and an engine time of 1,115.1 hours. The last engine maintenance was performed on December 22, 1999, at a tachometer time of 1,340 hours (224.9 hours after the annual inspection). The total time on the airframe on December 22, 1999, was estimated at 2,468.2 hours. No evidence of uncorrected discrepancies was found in the maintenance records. METEOROLOGICAL INFORMATION McAlester Flight Service Station personnel reported that the pilot obtained a limited weather briefing for the flight from McAlester to Altus, Oklahoma. The pilot requested and was given the winds aloft at 6, 9, and 12 thousand feet, which were 310 degrees at 28 knots, 310 degrees at 27 knots, and 300 degrees at 30 knots respectively. Per his request, he was also advised that there were no flight precautions along the planned route of flight. At 0553, the surface observation at McAlester was clear skies and calm wind with a temperature of 33.8 degrees Fahrenheit. The altimeter setting was 30.20 inches of Mercury. The U. S. Naval Observatory reported sunrise for McAlester, Oklahoma, at 0729. Witnesses reported calm wind and clear skies. WRECKAGE AND IMPACT INFORMATION The accident site was located 16 nautical miles on the 122-degree radial from the McAlester VOR and 18 nautical miles on a 125-degree magnetic heading from the McAlester Regional Airport. The wreckage distribution path was on a measured magnetic heading of 230 degrees and extended for 147 feet to the main wreckage. Portions of wing skin were found 57 feet beyond the main wreckage. The initial impact point was in 15 to 20-foot tall trees which had broken branches. Numerous portions of wings, ailerons, spars, and flaps were found distributed among the base of the trees. At 62 feet from the initial tree, a portion of metal from the left flap was stuck into a tree trunk at 18 feet agl. The initial ground impact crater (4 feet, by 8 feet, by 2 feet) was found 93 feet from the initial tree. Portions of engine baffling were found in the crater. Part of the flaps, one propeller blade, and pieces of the green navigation lens (right wing) were found near the periphery of the crater. The left wing speed brake (s/n 4005) was found in the stowed position and separated from the left wing. The right wing speed brake (s/n 4004) was found deployed and remained with the right wing. Flight control continuity was confirmed to the rudder and elevators. Deformation and fire destruction precluded a determination of continuity for the ailerons and the flaps. The cockpit and instrument panel were destroyed. No evidence of an in-flight fire was found at the accident site. According to the manufacturer, the flap jackscrew measurement of 2 3/8 inches would place the flaps in the retracted position. According to the manufacturer, the gear actuator measurement of 3 inches would place the gear in the retracted position. The electrical system of the airplane was found destroyed. All parts of the airplane, except the right aileron counterweight and the fuel selector valve, were accounted for in the wreckage debris. The engine and its accessories exhibited impact damage. Thermal damage and impact distortion precluded post-accident rotation of the turbocharger shaft. The three propeller blades were all separated from the propeller hub and exhibited twisting and bending. One of the propeller blades exhibited leading edge gouges. MEDICAL AND PATHOLOGICAL INFORMATION The autopsy was performed on December 28. 1999, at the Office of the Chief Medical Examiner, Tulsa, Oklahoma. Aviation toxicological testing was performed by the FAA Civil Aeromedical Institute (CAMI) Forensic Toxicology and Accident Research Center at Oklahoma City, Oklahoma. The toxicological tests were positive for the following drugs: 1.509 (ug/ml) phenobarbital detected in kidney; 1.65 (ug/ml) phenobarbital detected in muscle; 2.183 (ug/ml) tramadol detected in kidney; 1.356 (ug/ml) tramadol detected in lung; and a non quantified amount of nordiazepam and phenolpropane detected in kidney and lung; and a non quantified amount of chlorpheniramine detected in kidney. The toxicology was positive for ethanol, acetaldehyde, and N-Propanol. According to Dr. Canfield (CAMI), and Dr. Salazar (FAA Southwest Regional Flight Surgeon), several medications could have impaired the pilot. The most significant was the pain medication tramadol, which was detected at therapeutic concentrations. In addition, phenobarbital, nordiazepam, chlorepheniramine, pseudoephedrine, and phenylpropanolamine could have contributed to the impairment. No alcohol ingestion prior to death was detected; however, some post-mortem alcohol was present. A review by the NTSB medical officer of the records maintained on the pilot by the FAA Civil Aeromedical Institute Aeromedical Certification Division indicated that the pilot had a history of substance abuse involving cocaine and other substances. The records indicated that the pilot completed treatment for chemical dependency in October of 1986. The following medical information was extracted by NTSB medical officer from the medical records maintained on the pilot by the McAlester Clinic, Inc.: October 14, 1991, letter from private physician to the pilot notes "your chemical profile appears to show typical Gilbert's syndrome. Enzyme induction with Phenobarbital, as you know, can be helpful to lower the bilirubin level. Enclosed is a prescription for phenobarbital, as we discussed." The following medical information was extracted by NTSB medical officer from the medical records maintained on the pilot by the Jackson County Memorial Hospital: September 9, 1999, the pilot underwent surgery for "partial rotator cuff tear of the left shoulder." Medications are noted as "occasional Phenobarbital 15 mg per day." Discharge summary indicated "Medications: Vicoprofen [hydrocodone and ibuprofen]/Keflex [cephalexin]." The following medical information was extracted by NTSB medical officer from the pharmacy records maintained on the pilot by Clinic Pharmacy in Altus, Oklahoma, and Wood's Pharmacy in McAlester, Oklahoma: In the 30 days prior to the accident, the pilot filled prescriptions at the above pharmacies for 50 tablets containing 7.5 mg of hydrocodone, 30 tablets containing 10 mg of zolpidem, 60 tablets containing 350 mg of carisoprodol, and 120 tablets containing 50 mg of tramadol. In the 6 months prior to that, the pilot filled prescriptions at the above pharmacies for a total of 320 tablets containing 7.5 mg of hydrocodone, 180 tablets containing 10 mg of zolpidem, 50 tablets containing 350 mg of carisoprodol, 360 tablets containing 50 mg of tramadol, and 100 tablets containing 15 mg of phenobarbital. In one-30 day period approximately 6 months prior to the accident, the pilot filled prescriptions totaling 210 tablets containing 7.5 mg of hydrocodone. TEST AND RESEARCH On February 3, 2000, Precise Flight, Inc., at Bend, Oregon, under the supervision of their FAA project manager, completed a visual examination, inspection, and functional test on the damaged speed brake units. The examination for the right wing speed brake (s/n 4004) found that the blades were bent aft and "appear[ed] to have been in fully deployed position during impact." All indications were that the right speed brake cartridge "would have functioned normally prior to impact." The examination of the left wing speed brake (s/n 4005) "suggest[ed] speed brake blades appear to have been retracted at time of impact" and the speed brake cartridge assembly "operated correctly prior to impact." According to the Supplemental Type Certificate issued to Precise Flight, Inc., November 3, 1988, and the FAA approved flight manual supplement, the Precise Flight Speed Brake System (SBS) may be installed in the Mooney M20K. The SBS push button switch located on the pilot's control wheel features a push/on (in)-push/off (out) position to fully deploy and retract the speed brakes. The SBS safety toggle switch, located near the engine control console, features a pull out and up action to fully deploy the speed brakes, and out and down to retract the speed brakes. The SBS receives electrical power from the aircraft electrical buss through a disconnect type circuit breaker. The FAA approved flight manual supplement for the operating procedures states in part: BEFORE TAKEOFF a. Place the SBS switch in an "on" position to deploy speed brakes. b. Place the SBS switch in an "off" position to retract speed brakes. The procedure during takeoff and en route states in part: Speed brake switch off. According to the manufacturer's representative, the speed brakes were designed to automatically retract during an electrical system fluctuation/interrupt. On October 19, 1988, Precise Flight, Inc., tested a Mooney M20J, N57186, with only a left speed brake panel deployed. Results were 10% of corrective aileron travel and 5 lb. of rudder pressure required for coordinated flight from stall through Vne. In a letter dated, December 8, 1988, the FAA stated that the testing showed no significant effect on handling qualities with one speed brake deployed. ADDITIONAL INFORMATION The airplane was released to the owner's representative on April 21, 2000.

Probable Cause and Findings

The pilot's failure to maintain aircraft control. Factors were the pilot's impairment (drugs), the deployed right speed brake, and the night conditions.

 

Source: NTSB Aviation Accident Database

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