History of Flight
On September 7, 2010, about 1320 Central Daylight Time, a Cessna T210N, N2081U, sustained substantial damage following an in-flight breakup and subsequent impact with trees and terrain near Mountain Home, Arkansas. The airplane was registered to Monterey Bay Aviation, Incorporated, Watsonville, California. The cross-country flight originated at Vermilion Regional Airport, Danville, Illinois, about 0930 and was en route to Georgetown, Texas. No flight plan was filed, but the pilot was receiving radar flight following from Memphis Air Route Traffic Control Center (ARTCC).
The pilot contacted Memphis ARTCC at 1245. The controller asked if the pilot could see the precipitation around the Flippin VOR. The pilot replied “Roger.” The airplane was flying on about a 235-degree heading at 6,700 feet msl. At 1305, the controller reported a large area of precipitation 30 miles ahead and later directed the pilot to a new frequency. At 1307, the pilot checked in and was informed of heavy to extreme precipitation 15 miles ahead for 180 miles.
At 1317, the pilot requested a descent to 4,500 feet “for VFR.” The controller cleared the pilot to maintain VFR. At 1318:51, the airplane turned left to about 160 degrees, then right back to the southwest. Radar contact was lost at 1320:40, 7 nautical miles south of FLP at 6,600 feet msl. The controller broadcast that he had lost the airplane on radar; the pilot did not respond.
Witnesses reported hearing the engine “revving up and down” but could not see the airplane due to an overcast layer. Moments later, the airplane appeared from clouds and was observed descending in a nose-down spiral. Before descending out of sight, one wing “appeared to fold.”
Personnel Information
The 62-year-old pilot in the left seat held a private pilot certificate with a single-engine land rating. His logbook showed he flew 2.0 hours with an instructor in the accident airplane on July 18, 2010, and completed a flight review on July 7, 2010. He held a third-class medical certificate dated June 15, 2010, with the limitation “Holder shall possess glasses which correct near.” He reported 2,000 total hours and 20 hours in the previous six months.
The 32-year-old pilot in the right seat held a private pilot certificate with a single-engine land rating. No logbooks were found for him; he did not hold a current medical certificate. His last medical application was November 23, 2005, when he reported 120 total hours and none in the previous six months.
Aircraft Information
The airplane was a 1982 Cessna Model T210N, serial number 21064764, powered by a Teledyne Continental Motors TSIO-520-R engine. According to the logbook, it underwent an annual inspection on November 20, 2009, with a tachometer reading of 87.2 hours. An October 18, 2009 entry recorded an airframe time of 426.4 hours after repainting.
Meteorological Information
A National Weather Service surface analysis at 1300 depicted a stationary front extending across southeastern Missouri into northern Arkansas and Oklahoma. Tropical Storm Hermine was located to the southeast over southern Texas. A deformation zone was indicated by wind flow over southern Missouri and Arkansas. Station models showed extensive rain along and south of the front.
A Radar Summary Chart showed a large area of intense to extreme echoes over Oklahoma and northern Arkansas. A Convective Outlook indicated a general risk of thunderstorms with a slight risk of severe thunderstorms over southern Texas.
At 1253, Baxter County Airport (BPK) reported wind from 170° at 5 knots, visibility 9 miles, ceiling broken at 2,900 feet, overcast at 3,800 feet, temperature 78°F, dew point 71°F, altimeter 30.12 inHg. At 1315, a special observation reported wind 200° at 8 knots gusting to 14 knots, visibility 9 miles, ceiling broken at 3,300 feet, overcast at 4,700 feet. At 1349, light rain began; visibility 9 miles, few clouds at 600 feet, overcast at 5,000 feet.
Harrison Airport (HRO) at 1328 reported wind 170° at 4 knots, visibility 2.5 miles in moderate rain and mist, few clouds at 1,300 feet, scattered at 2,700 feet, overcast at 3,400 feet.
Springfield WSR-88D radar at 1319 showed a large east-to-west band of echoes with 35-40 dBZ over the accident site and maximum 50 dBZ echoes 12 miles east. FAA Advisory Circular AC00-24B identifies 35-40 dBZ as possible moderate to severe turbulence with lightning.
Terminal Aerodrome Forecasts issued at 0623 expected winds 210° at 9 knots, visibility >6 miles with showers, scattered clouds at 5,000 feet, ceiling broken at 9,000 feet, with temporary conditions of visibility 4 miles in thunderstorms between 1500 and 1900 CDT.
Wreckage and Impact Information
The main wreckage was located in a heavily wooded area 5 miles south of Mountain Home. The debris field covered about 3,850 feet along a line from the main wreckage extending north on about a 001° magnetic heading. The main wreckage consisted of the cabin, fuselage, right wing, landing gear, and engine, lodged in trees. The fuselage was oriented on a 262° heading. The cowling, cabin area, instrument panel, glareshield, and seats were broken open, charred, and consumed by fire. The inboard portion of the right wing was charred. Flight control continuity was established.
The engine was broken out but intact, resting on its left side. The propeller hub was broken at the flange; one blade remained with the hub, curled forward with torsional bending and scratches. Two other blades were broken out and nearby, also showing torsional bending and scratches.
Separated components extended north: at 300 feet, the center section of the horizontal stabilizer and elevator; at 1,350 feet, the outboard right horizontal stabilizer; at 1,900 feet, the outboard left elevator; at 2,300 feet, the vertical stabilizer broken aft at the base; at 2,350 feet, the top third of the rudder; at 2,850 feet, the left wing bent upward, twisted, and broken aft at the root, with spars broken upward and twisted aft, and aileron control cables showing overload failures; at 3,850 feet, the outboard half of the left aileron.
Medical and Pathological Information
Autopsies were performed on both pilots on September 9, 2010. Toxicology tests for the 32-year-old pilot were negative. Tests for the 62-year-old pilot showed volatile ethanol in muscle tissue at 21 mg/dl, attributed to postmortem formation, not ingestion.
Tests and Research
Examination of the engine on September 9, 2010, at Clinton, Arkansas, revealed no abnormalities that would have prevented normal operation and production of rated horsepower. Other airplane systems showed no preimpact anomalies.