Aviation Accident Summaries

Aviation Accident Summary DEN05FA074

Ouray, CO, USA

Aircraft #1

N6807R

Cessna T210G

Analysis

The airplane was reported missing and the Civil Air Patrol located the wreckage near Mt. Whitehouse. A debris path, approximately 1/2 mile wide and 1 1/2 miles long was located in mountainous terrain, varying in elevation from 10,000 feet to 12,800 feet mean seal level. National Track Analysis Program radar data depicted the accident flight from 1252:27 until 1856:17, and the altitude varied from 17,500 feet msl to 19,200 feet msl. The aircraft ground speed during this time was measured to be between 124 knots and 314 knots. No flight plan had been filed and no weather briefing had been obtained. An Airman's Meteorological Information (AIRMET) for occasional moderate turbulence below FL180 (Flight Level 18,000 feet) was valid. The last radar return from the accident airplane was located within this advisory area. In addition, an AIRMET for occasional moderate turbulence between FL180 and FL410 and possible mountain wave action had been issued. The last radar return from the accident airplane was located within this advisory area. The right wing was located 4,461 feet (0.8 miles) west of the main wreckage at an elevation of 11,175 feet msl. The left wing was located 2,772 feet (0.5 miles) west of the main wreckage at an elevation of 11,500 feet msl.. The debris path started with the right wing and continued in an easterly direction towards the main wreckage. The propeller was located directly above the main wreckage at an estimated altitude of 12,800 feet msl. The fuselage, engine, propeller, horizontal stabilizer, and elevator were not recovered. These could not be examined for anomalies. The airplane's systems, including the vacuum, pitot static, electrical, and powerplant, could not be examined for anomalies. No evidence of fatigue cracking or other type of preexisting fracture was noted within the recovered wings. No record of a preflight or in-flight weather briefing, obtained by the pilot, was located.

Factual Information

HISTORY OF FLIGHT On May 11, 2005, at 1256 mountain daylight time, a Cessna T210G, N6807R, operated by a private pilot, was destroyed when it impacted terrain 3 nautical miles northwest of Ouray, Colorado. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The pilot and three passengers were fatally injured. The cross-country flight departed Page Municipal Airport (PGA), Page, Arizona, approximately 1150 and was en route to Kelly Airpark, Elbert, Colorado. Concerned family members reported the airplane missing on May 12, 2005. The Civil Air Patrol (CAP) located the wreckage, near Mt. Whitehouse, at approximately 1700 mountain daylight time on May 13, 2005. A debris path, approximately 1 1/2 miles long and 1/2 mile wide was located in mountainous terrain, varying in elevation from 10,000 feet to 12,800 feet mean seal level (msl). According to the family, the airplane departed California early in the morning on May 11, 2005. The airplane landed at PGA, and according to airport personnel and fuel receipts, the airplane took on 30 gallons of fuel; 20 gallons in the left tank and 10 in the right tank. The fueler stated that he did not top off the fuel tanks and that the airplane departed shortly after the fueling services. No other services were rendered. National Track Analysis Program (NTAP) radar data depicted the accident flight, progressing in an easterly direction, at an altitude of 18,000 feet msl, from 1243:00 until 1252:17. From 1252:27 until 1856:17, the altitude varied from 17,500 feet msl to 19,200 feet msl. The NTAP recorded the last radar information at 1856:17, in a location of 38 degrees, 02 minutes, 23 seconds north latitude, and 107 degrees, 45 minutes, 24 seconds west longitude, and an encoded altitude of 19,200 feet msl (2.7 miles west of the main wreckage). The aircraft ground speed during this time was measured to be between 124 knots and 314 knots. PERSONNEL INFORMATION The pilot, age 59, held a private pilot certificate issued on January 20, 2000, with an airplane single engine land and instrument rating. He held a third class airman medical certificate issued on February 28, 2005. The certificate contained the limitation "must wear corrective lenses." At the time of medical application, the pilot reported a total flight time of 1,350 hours, 100 hours of which had been flown in the previous 6 months. According to the insurance company, the pilot had reported a total time of 1,360 hours, 1,210 hours of which had been logged in the make and model of the accident airplane. AIRCRAFT INFORMATION The accident airplane, a Cessna T210G (serial number T210-0207), was manufactured in 1967. It was registered with the Federal Aviation Administration (FAA) on a standard airworthiness certificate for normal operations. The airplane was equipped with a Continental TSIO-520M6B, S/N: 532139 with a rated maximum continuous BHP of 285 at 2700 RPM and a rated maximum take-off BHP of 310 at 2700 RPM. The engine was equipped with a three bladed, controllable pitch McCauley propeller. The airplane was registered to and operated by Robert R. Ford Trucking Incorporated, located in Chino, California, and was maintained under an annual inspection program. A review of the maintenance records indicated that an annual inspection had been completed on March 15, 2005, at a tachometer time of 815 and an airframe total time of 4,225 hours. At the same time, a new aft bulkhead, wet vacuum pump, and new stall-warning unit were installed. On April 9, 2005, the standby vacuum system was removed. METEOROLOGICAL INFORMATION The closest official weather observation station was Telluride Regional Airport (TEX), Telluride, Colorado, located 9 nautical miles west, southwest, of the accident site. The elevation of the weather observation station was 9,078 feet msl. The aviation routine weather report (METAR), taken at 1248, reported winds, 190 degrees at 7 knots, varying from 160 to 230 degrees; visibility, 10 statute miles or greater; sky condition, clear; temperature 6 degrees Celsius (C); dewpoint, minus 14 degrees C; altimeter 29.94 inches. An Airman's Meteorological Information (AIRMET) for occasional moderate turbulence below FL180 (Flight Level 18,000 feet) was valid for Arizona, New Mexico, and the southern half of Colorado. The last radar return from the accident airplane was located within this advisory area. In addition, an AIRMET for occasional moderate turbulence between FL180 and FL410 and possible mountain wave action for Colorado and portions New Mexico had been issued. The last radar return from the accident airplane was located within this advisory area. No record of a preflight or in-flight weather briefing, obtained by the pilot, was located. WRECKAGE AND IMPACT INFORMATION Due to deep snow, rugged terrain, and avalanche danger, the National Transportation Safety Board did not travel to the accident scene. According to the search and rescue teams, and civil air patrol, the accident site was located in mountainous terrain. A global positioning system (GPS) receiver recorded the main wreckage location as 38 degrees, 01.73 minutes north latitude and 107 degrees, 43.59 minutes west longitude. The elevation of the main wreckage was 11,524 feet msl. A GPS receiver recorded the right wing location as 38 degrees, 01 minutes, and 57.278 seconds north latitude and 107 degrees, 44 minutes, 28.586 seconds west longitude. The elevation of the right wing was 11,175 feet msl. The right wing was located 4,461 feet (0.8 miles) west of the main wreckage on a magnetic bearing of 67 degrees (to the main wreckage). A GPS receiver recorded the left wing location as 38 degrees, 02 minutes, and 1.793 seconds north latitude and 107 degrees, 44 minutes, 1.544 seconds west longitude. The elevation of the left wing was 11,500 feet msl. The left wing was located 2,772 feet (0.5 miles) west of the main wreckage on a magnetic bearing of 120 degrees (to the main wreckage). The debris path started with the right wing and continued in an easterly direction towards the main wreckage. Portions of the interior panel, the left wing, a door, an inner door panel, and Plexiglas were all located within the debris path. The propeller was located directly above the main wreckage at an estimated altitude of 12,800 feet msl. Photographs of the propeller, provided by the CAP showed the propeller stuck in deep snow. A ground scar in the snow preceded the propeller and continued downhill, past the point where the propeller came to rest. A photograph of the airplane fuselage, provided by the CAP, illustrated that the fuselage, to include the cabin, firewall, instrument panel, and engine, was destroyed. The fuselage, engine, propeller, horizontal stabilizer, and elevator were not recovered. These could not be examined for anomalies. The airplane's systems, including the vacuum, pitot static, electrical, and powerplant, could not be examined for anomalies. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy was performed by Montrose Memorial Hospital, Division of Forensic Pathology, on May 20, 2005, as authorized by the Ouray Country Coroner's Office. During the autopsy, tissue samples were retained for toxicological purposes. The autopsy revealed the cause of death due to "multiple traumatic injuries." A toxicology was performed by the Federal Aviation Administration's Civil Aerospace Medical Institute, Oklahoma City, Oklahoma. Tests for carbon monoxide and cyanide were not performed. No ethanol was detected in the liver or muscle. Morphine, Citalopram, N-Desmethylcitalopram, DI-N-Desmethylcitalopram, and Phentermine were detected in the liver and kidney. Levels of Butalbital (2.301 ug/ml, ug/g in the liver and 2.318 ug/ml, ug/g in the kidney), and Codeine (0.511 ug/ml, ug/g in the liver and 0.786 ug/ml, ug/g in the kidney) were detected. According to the pilot's family and primary care medical records, he may have been taking Fiorinal #3 for back pain in addition to Celexa for stress management. The pilot was admitted to the hospital on May 6, 2005, for an "altered level of consciousness and periorbital cellulitis." He was discharged from the hospital on May 7, 2005, with the diagnosis of "periorbital cellulitis of the right eye." TESTS AND RESEARCH The left and right wings and the vertical stabilizer were recovered and relocated to a hangar in Greeley, Colorado, for further examination. The left wing separated from the fuselage at the wing root. The entire wing was bowed down, and exhibited wrinkled, torn, and scratched metal along its entire span. The outboard portion (33 inches) of the aileron had separated. The right wing separated from the fuselage at the wing root. The entire wing was bowed down at midspan, along the rivet line, between the flap and the aileron. The wing exhibited wrinkled, torn, and scratched metal along its entire span, and accordion crushing from the wing spar aft at the wing root. Control continuity to both ailerons and flaps was confirmed to the wing roots only. Inboard portions of the left and right wing, including the spar, and a midspan portion of the right wing spar, were sent to the National Transportation Safety Board, Office of Research and Engineering, Materials Laboratory Division, for further examination. Visual examinations of the various fractures in the submitted pieces revealed features typical of overstress separation. No evidence of fatigue cracking or other type of preexisting fracture was noted. The inboard portion of the left wing was fractured on its inboard side. The leading edge fuselage-to-wing attachment fittings were fractured, and slight compression buckling on the upper sides of the fractured fittings consistent with an upward bending load. The main spar for the left wing was located approximately 2 feet aft of the leading edge attachment point. The inboard end of the upper spar cap was bent downward. The upper skin of the wing around the bent upper cap contained spanwise scraping marks, and some portions of the skin directly above the spar cap had been pushed and folded in an outward direction, all consistent with movement of the upper side of the left wing into other structure during the wing separation process. The vertical flange of the upper cap was fractured where it blended into the main portion of the cap over the length of spar where the upper cap that was deformed downward. Within 13 inches of the inboard end of the lower spar cap, the cap's vertical flange was sheared through fastener holes, consistent with motion of the lower cap in the outboard direction relative to the fasteners. The inboard ends of the upper and lower spar caps contain a strap on the forward side and a strap on the aft side of each cap's vertical flange. On the left wing spar, these straps were fractured about 13 inches outboard of the inboard ends of the caps. The inboard portion of the left wing spar was cut out of the remainder of the wing piece in order to more easily view the fractured ends of the straps. Significant out-of-plane deformation was not found adjacent to the strap fractures. It was also noted that the spar web members were fractured approximately in line with the strap fractures, and that the web adjacent to the fracture contained 45 degree compression wrinkles, consistent with excessive upward loading. After the left wing spar was removed from the remainder of the wing section, very heavy smearing was noted on the fracture surface of the vertical flange of the lower spar cap, consistent with contact from fasteners and other structure during the fracture process. The portion of the right wing included a portion of the main spar and wing skin forward of the spar. The structure was also fractured on its inboard end. The main spar was fractured approximately 15 inches outboard of the inboard end of the wing skin. The inboard end of each element in the spar was bent in the aft direction adjacent to the fracture, consistent with the wing outboard of the fracture moving in the aft direction as the fracture occurred. It was also noted that the upper wing skin, the lower wing skin, and the rib at the fracture location (inboard rib for a fuel tank) all contained buckling deformation adjacent to the main spar, consistent with aft loads on this structure. The wing structure forward of the spar was deformed in the aft direction, and the inboard ends of the pieces of this structure were folded up and aft. The midspan portion of the right wing spar was fractured through the lower spar cap and upward through the lower 75 percent of the spar web approximately in line with the lower spar cap fracture. The forward portion of the lower cap was bent aft, twisted, and deformed at the fracture area. The horizontal flange on the aft side of the lower cap was slightly buckled at a location 14 inches outboard of the lower cap fracture, and was significantly buckled (and the cap bent) at a location 12 inches inboard of the lower cap fracture. In addition, the vertical web of the upper cap was fractured and split from the upper cap over an 8-inch length above the lower cap fracture. The lower wing skin aft of the lower cap fracture area was also heavily deformed in the aft direction. The fracture features and deformation patterns on this piece of the spar were consistent with a local impact to the lower portion of the spar in the aft direction. ADDITIONAL INFORMATION Parties to the investigation include Cessna Aircraft Company, and the Federal Aviation Administration, as represented by an inspector from the Salt Lake City Flight Standards District Office. The wreckage was released to the insurance company representing the pilot's estate on June 8, 2006. This narrative was modified on August 31, 2006.

Probable Cause and Findings

the pilot's inadvertent flight into adverse weather conditions, loss of control, and resulting exceedence of the design stress limits of the aircraft. which led to an in-flight structural failure. Factors in the accident included the pilot's inadequate preflight and in-flight planning and decision making, the severe turbulence, and the mountain wave.

 

Source: NTSB Aviation Accident Database

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