NTSB Factual Report

HISTORY OF FLIGHT

On August 23, 2010, approximately 1030 mountain daylight time, a Cessna 310C, N896H, was substantially damaged when it impacted terrain four miles southeast of Calhan, Colorado. Visual meteorological conditions prevailed at the time of the accident. The instructional flight was being conducted under the provisions of 14 Code of Federal Regulation Part 91 without a flight plan. The commercial pilot and certified flight instructor (CFI) were fatally injured. The local flight departed Meadow Lake Airport (KFLY), Colorado Springs, Colorado, approximately 1000.

Friends and family members reported that the two pilots departed that morning with the objective of completing a flight review for the commercial pilot. A friend of the CFI reported speaking with him just prior to the flight. It was anticipated that it would be a quick, routine checkride, with no issues.

According to the Federal Aviation Administration (FAA), the airplane was "maneuvering in the practice area" and was receiving radar flight following services from Colorado Springs approach. A review of the radar data revealed that the airplane's radar track initiated at 1000 just east of KFLY at an altitude of 8,300 feet mean sea level (msl). The airplane maneuvered to the south and east of KFLY. The airplane climbed to an altitude of 10,000 feet and initiated a left turn just prior to the track being lost at an altitude of 7,200 feet msl at 1029. The wreckage of the airplane was located in a field just after 1100 by a local resident, directly below the last radar hit.

PERSONNEL INFORMATION

Commercial Pilot

The commercial pilot, age 76, held a commercial pilot certificate with airplane single engine, multiengine, and instrument ratings. He was issued a special issuance third class airman medical certificate on January 13, 2010. The certificate contained the limitation "not valid for any class after January 31, 2012."

At the time of medical certificate application, the commercial pilot reported a total time of 3,425 hours, 10 hours of which were logged in the preceding six months.

CFI

The CFI, age 60, held an airline transport pilot certificate with a multiengine airplane rating and a commercial pilot certificate with airplane single engine and rotorcraft helicopter ratings. He also held a flight instructor certificate with airplane single and multiengine, airplane instrument, and rotorcraft helicopter ratings. He was issued a first class airman medical certificate on October 13, 2008. The certificate contained no limitations.

At the time of medical certificate application, the CFI reported a total time of 3,850 hours, 140 of which were logged in the preceding six months.

AIRCRAFT INFORMATION

The accident airplane, a Cessna 310C (serial number 35996), was manufactured in 1959. It was registered with the FAA on a standard airworthiness certificate for normal operations. Two Teledyne Continental Motors IO-470-D engines rated at 260 horsepower at 2,625 rpm powered the airplane. Each engine was equipped with a 2-blade, Hartzell propeller.

The airplane was registered to and operated by the pilot, and was maintained under an annual inspection program. A review of the maintenance records indicated that an annual inspection had been completed on August 3, 2009, at an airframe total time of 4,370.7 hours, and an airplane hobbs time of 1,953.0 hours. The airplane had flown 4.8 hours between the last inspection and the accident and had a total airframe time of 4,375.5 hours.

METEOROLOGICAL CONDITIONS

The closest official weather observation station was The City of Colorado Springs Municipal Airport (KCOS), Colorado Springs, Colorado, located 25 nautical miles (nm) southwest of the accident site. The elevation of the weather observation station was 6,187 feet msl. The routine aviation weather report (METAR) for KCOS, issued at 0954 reported winds 060 degrees at 17 knots, visibility 10 miles, sky condition scattered clouds at 11,000 feet, temperature 26 degrees Celsius (C), dew point 11 degrees C, altimeter 30.24 inches.

WRECKAGE AND IMPACT INFORMATION

The airplane came to rest, upright, in an open field characterized by short grass and rolling terrain, oriented on a measured heading of 358 degrees. The elevation was recorded as 6,878 feet msl. The main wreckage consisted of the fuselage, empennage, both wings, and both engine and propeller assemblies.

The nose tip of the fuselage was unremarkable. The nose landing gear was pushed up and the top of the landing gear assembly protruded out of the top of the nose of the fuselage. The forward cabin area was crushed up in an accordion manner. The Plexiglas windscreen was fragmented and the instrument panel was dislodged with several of the instrument faces being fragmented. The aft portion of the fuselage and empennage illustrated upward accordion crushing on the bottom or belly of the fuselage and empennage.

The following instrument indications were observed:

Airspeed Indicator - destroyed

Altimeter - 7,000 feet - short needle missing, Kollsman window 30.23

Vertical Speed Indicator - 980 feet per minute descent

ADF - destroyed

Attitude Gyro - destroyed

Heading Gyro - 118

The following miscellaneous switch positions and instrument indications were observed:

Right Engine Fuel selector - Main tanks

Left Engine Fuel selector - Main tanks

Auxiliary Fuel Pump - Left pump on - Right pump switch broken

The skin on the left side of the empennage and fuselage was torn. The empennage consisted of the horizontal and vertical stabilizers, rudder, and elevator assemblies.

The forward portion of the vertical stabilizer which attached to the aft portion of the fuselage separated and the entire empennage was canted to the right. The bottom portion of the rudder skin was creased to the right. The upper counter balance weight separated from the top portion of the rudder and was located 55 feet south of the main wreckage. A dark blue paint transfer mark was noted on the right side of the rudder, near the third rivet line up from the bottom of the control surface. The lower tail cone paint was fragmented. The rudder and vertical stabilizer were otherwise unremarkable.

The leading edge of the left horizontal stabilizer was unremarkable and the outboard trailing edge was wrinkled. The left elevator was creased and wrinkled. The skin on the right horizontal stabilizer and elevator was wrinkled along the upper portion of the control surface. The leading edge of the horizontal stabilizer was unremarkable.

Control continuity was established to the rudder and elevator flight controls.

The right wing remained attached to the fuselage at the wing root and included the right aileron, right flap assembly, right main landing gear assembly, and right engine and propeller assembly. The right main landing gear was extended and the tire was deflated. The outboard tip tank was split open and partially separated from the wing.

The right aileron was partially separated from the right wing at the outboard hinge attach point. The right aileron balance and control cables were continuous from the control surface inboard to the fuselage and forward to the flight control yoke. Flap pushrod continuity was confirmed.

The right engine remained attached to the right wing. One propeller blade separated at the blade hub and was embedded in the ground, directly beneath the wreckage of the airplane. This blade was labeled R-B for identification purposed only. The blade was muddy, oily, and exhibited span-wise scoring on the face of the propeller blade. The separated propeller blade also exhibited an "S" bend. Blade R-A remained attached to the engine at the propeller flange and was unremarkable.

The oil fill cap remained attached to the oil filler tube by the retainer chain and was located between cylinder numbers 4 and 6. Oil was present on the external portion on the inboard side of the engine. The engine crank case was cracked in several locations and the fuel pump and both magnetos separated from the engine. The engine cowling was crushed and wrinkled.

The left wing remained attached to the fuselage at the wing root and included the left aileron, left flap assembly, left main landing gear assembly, and left engine and propeller assembly. The skin at the wing root, along the fuselage was crushed up and wrinkled. The outboard tip tank was split open along the rivet line and partially separated from the wing. The fuel bladder material was torn and fragmented. The left main landing gear was extended and the tire was deflated.

The left aileron was partially separated from the left wing at the outboard hinge attach point. The left aileron balance cable continuity was established from the control surface inboard to the fuselage and forward to the flight control yoke. The left aileron control cable was separated near the landing gear wheel well in overload due to impact damage. Flap pushrod continuity was confirmed.

The left engine remained attached to the left wing. Both propeller blades were oriented horizontally, level with the left wing. The inboard positioned propeller blade labeled L-A exhibited 45 degree chordwise scratches on the blade face. The propeller blade face "L-A" also exhibited polishing on the cambered side of the propeller blade. The outboard propeller blade labeled L-B was unremarkable. The engine cowling was crushed and wrinkled.

MEDICAL AND PATHOLOGICAL INFORMATION

Commercial Pilot

The El Paso County Coroner's Office performed the autopsy on the pilot on August 24, 2010, as authorized by the El Paso County Coroner. The autopsy concluded that the cause of death was multiple blunt force injuries.

The FAA's Civil Aerospace Medical Institute, Oklahoma City, Oklahoma, performed toxicological tests on specimens that were collected during the autopsy (CAMI Reference #201000222002). Results were negative for carbon monoxide, cyanide, and volatiles. Testing of the urine revealed candesartan.

CFI

The El Paso County Coroner's Office performed the autopsy on the CFI on August 24, 2010, as authorized by the El Paso County Coroner. The autopsy concluded that the cause of death was multiple blunt force injuries.

The FAA's Civil Aerospace Medical Institute, Oklahoma City, Oklahoma, performed toxicological tests on specimens that were collected during the autopsy (CAMI Reference #201000222001). Results were negative for carbon monoxide, cyanide, and drugs. Testing of the muscle detected 67 mg/dL of ethanol and testing of the muscle and brain tissue detected 1 mg/dL, respectively, of methanol. The report noted that the results were due to postmortem ethanol formation and not the ingestion of ethanol.

TESTS AND RESEARCH

The wreckage was recovered and relocated to Greeley, Colorado. The engines were examined by investigators from the NTSB, Cessna Aircraft, and Teledyne Continental Motors. Both engines were rotated through, by hand, and valve and air movement was noted with all six cylinders. Both engine driven fuel pumps were free to rotate and the splines were continuous. The engine driven magnetos produced a blue spark at each lead when rotated by hand. Normal operating signatures were present.

An examination of the fuel boost pumps revealed no anomalies.

NTSB Probable Cause

The pilots'failure to maintain control of the airplane which resulted in an inadvertent stall and spin.