NTSB Factual Report

HISTORY OF FLIGHT

On October 4, 2000, about 0931 Pacific daylight time, a Cessna 182S, N2373D, descended into a pond about 2.3 nautical miles west of the Sonoma County Airport, Santa Rosa, California. Dragonfly Aviation, Inc., was operating the airplane under the provisions of 14 CFR Part 91. The pilot owned and operated a Cessna 206. It was receiving maintenance, and the pilot rented the accident airplane from a local fixed base operator to fly to a business meeting in Concord, California. During the impact sequence, the rented airplane was destroyed, and it sank in a pond to an estimated 50-foot depth. The pilot was fatally injured. Instrument meteorological conditions prevailed, and an instrument flight rules (IFR) flight plan was filed by the private pilot. The flight originated from Santa Rosa about 0927.

According to the Federal Aviation Administration (FAA), the pilot had requested and received an IFR departure clearance for the Santa Rosa Five Departure. He was then cleared to takeoff from runway 19 and climb to 5,000 feet, or until reaching visual conditions and canceling the IFR clearance. The prescribed departure procedure required the pilot to execute a right turn upon takeoff. Prior to taking off, the pilot read back the instrument clearance including the assigned transponder code of 3321.

At 0929:29, a radar controller from the Oakland Air Route Traffic Control Center (ARTCC) established radio contact with the airborne pilot. The pilot reported to the ARTCC controller that he was climbing through 1,100 feet mean sea level (msl).

At 0929:34, the controller acknowledged the pilot's transmission. Then, at 0930:15, the controller informed the pilot that he was not receiving the airplane's transponder signal. The controller advised the pilot to "verify squawking three three two one and say altitude leaving."

The pilot responded at 0930:23, and stated "sixteen hundred seven three delta." This was the last transmission recorded from the accident pilot. The controller subsequently indicated that, after he advised the pilot to verify his transponder code, "it came up and I got one hit" before the airplane disappeared from his radar a couple miles west of the airport.

Sonoma County Sheriff's Department personnel indicated that no witnesses reported having observed the airplane crash.

PERSONNEL INFORMATION

The pilot's personal flight record logbook was not provided for examination. Based upon information provided by acquaintances of the pilot from their examination of records associated with the operation of the pilot's own airplane (a Cessna 206), during the period between March 15, 2000, and September 10, 2000, the pilot had flown his Cessna 206 for 42 hours. During the preceding 12 months, from March 8, 1999, to March 8, 2000, the pilot had flown his airplane for 81.4 hours.

The operator (Dragonfly Aviation, Inc.) reported that the accident pilot had successfully completed a flight review on September 1, 2000. The certified flight instructor, who administered the review, did not recall having flown any instrument approaches during the flight.

Regarding the pilot's familiarity with the accident Cessna 182S, the operator reported it has no evidence that the accident pilot had previously flown or been checked out in this model of airplane.

The pilot was issued an instrument rating in September, 1996. The pilot's recent instrument flying experience was not determined.

On October 1, 1998, when the pilot was issued his most recent third-class aviation medical certificate, he indicated that his total flight time was about 600 hours.

AIRPLANE INFORMATION

The airplane was manufactured in 1999, and on September 13, 1999, it was issued an FAA airworthiness certificate. The airplane was equipped with dual, engine driven vacuum pumps and a two-axis autopilot.

Maintenance records indicated that in December 1999, and in April and June 2000, an engine oil analysis was performed for metal wear and other contaminants. According to the company that performed the analysis, all values appeared normal.

The airplane received its first annual inspection on June 21, 2000, at a total airframe and engine time of 102.0 hours. On September 7, 2000, the airplane received a 100-hour inspection at a total airframe and engine time of 199.8 hours. In the associated maintenance record write-up, the following notation was made: "Attitude gyro failed on post inspection run-up. Removed SN:T69688N. Installed new gyro SN: T73148P. Ops check ok."

On October 3, 2000, at a total airframe and engine time of 228 hours, the six top and six bottom spark plugs were replaced. This action was in response to a squawk received by the airplane's operator the previous day of an excessive magneto rpm drop. After the spark plugs were replaced the engine was run up, and no deficiencies were noted. Thereafter, according to the operator's contract mechanic, the airplane was returned to service.

METEOROLOGICAL INFORMATION

In pertinent part, at 0853 and 0953, Sonoma County Airport reported the following weather conditions: wind calm, visibility 7 and 6 miles, respectively, and an overcast ceiling at 600 feet above ground level. Also, during this period the temperature/dew point was reported at 12/10 degrees Celsius. According to an FAA air traffic controller, the top of the stratus cloud layer was 1,800 feet mean sea level.

AIDS TO NAVIGATION

According to the FAA, all electronic aids to navigation in the vicinity of the Sonoma County Airport were operating normally at the time of the accident.

WRECKAGE AND IMPACT INFORMATION

Sonoma County Sheriff's Department personnel reported that the airplane wreckage was located at the bottom of a manmade dredge pond in about 50 feet of water. The estimated position of the main wreckage was near 38 degrees 30.8 minutes north latitude by 122 degrees 51.7 minutes west longitude.

A diver, who was involved in the underwater wreckage recovery operation, provided a diagram indicating where principal components had been located. The diagram indicates that the engine and the cockpit's instrument panel were found about 20 feet north of the fuselage. Wing fragments were located next to the fuselage. The propeller blades were located separated from the hub and were found near the airplane's empennage. The underwater visibility was reported as being less than 1 foot.

MEDICAL AND PATHOLOGICAL INFORMATION

Family members and acquaintances described the pilot as having been in recent good health and active. Nothing atypical was reported regarding his behavior within 48 hours of the accident flight.

Following recovery of the pilot's body on October 5, 2000, an autopsy was performed by the Sonoma County Sheriff-Coroner, 3336 Chanate Road, Santa Rosa, California 95404.

According to the manager of the FAA's Toxicology and Accident Research Laboratory, tests on specimens from the pilot revealed no evidence of screened drugs. The ethanol found during the examination was from postmortem formation and not from the ingestion of ethanol.

TESTS AND RESEARCH

Under the direction and supervision of the National Transportation Safety Board investigator, the airframe and engine components were examined following their recovery from the pond. There was no evidence of fire.

Airframe Examination.

All portions of the observed wreckage were found impact damaged. In summary, the engine was found separated from the fuselage, which was observed crushed in an aft direction to the aft cabin area. The engine was found attached to the firewall and instrument panel. Two of the three propeller blades were recovered.

The wing flaps were found in a zero degree setting as evidenced by the position of the flap jack screw. The fuel tank selector valve was found set to the "both" position.

The recovered flight control surfaces were found fragmented and deformed. The following components were not located: the right elevator, the right lift strut, and the left wing flap. Attachment fittings associated with these components were found bent.

Both wing spars were found separated from the fuselage, mostly devoid of skin, and were fragmented. The left and right wing spar-to-fuselage attachment fittings were found intact. The spars were found broken at their carry through structure. Both wing spars were found broken at the mid span location in the vicinity of the wing lift strut attachment point. The left wing spar was found with its skin crushed in an aft direction. The right wing spar was observed crushed and fragmented in a manner similar to the left wing.

The left horizontal stabilizer and left elevator were observed bent in an upward direction at about a 45-degree angle. The left elevator was found separated at its attachment fittings. The right elevator's attachment fitting was found broken, and the stabilizer was found separated from the empennage.

Control cable continuity was confirmed between the cockpit and the rudder. Elevator control cable continuity was confirmed between the cockpit and the elevator horn. Separations in the flight control cables exhibited broomstraw signatures.

The instrument panel was destroyed. Neither the artificial horizon nor the directional gyroscope was located. The turn coordinator was found, and it was disassembled. Its gyro rotor bore circumferential score marks. The low vacuum warning indicator bulb was missing from the crushed instrument panel.

No evidence of oil streaking, charred material, or soot was noted on any component. The bundled instrument panel electrical wiring was externally viewed and no evidence of melted insulation material was noted.

Engine Examination.

The fuel screens were found clean. The main fuel line from the engine driven pump to the flow divider was observed broken at the pump end in an impact damaged area of the engine. Fuel was observed in the fuel servo and in the main fuel line to the fuel servo. In total, about 3/4 teaspoon of fuel was found in the fuel injector nozzle lines.

All of the spark plugs appeared wet, were contaminated with silt, and appeared in a "like new" condition according to the engine participant. Both magnetos were found internally wet. Their drive gears were rotated by hand, and spark was noted.

The engine was equipped with two vacuum pumps. The upper mounted pump was found free to rotate and appeared undamaged. Its drive coupling was found intact. The lower mounted pump's internal rotor was found fractured. Its drive coupling was also found intact. Water and silt were found in both pumps.

In summary, the participant reported that all observed damage to the engine case appeared impact related. No evidence was found of any preimpact mechanical malfunction with regard to the engine or engine-related accessories. See the participant's report for additional details.

Propeller Examination.

The propeller blades were found separated from the hub. They appeared torsionally twisted and had gouges in their leading edges. The blades were positioned against various surfaces on the engine where damage was observed. A cylinder cooling fin pattern was noted to correspond to the gouge pattern in one blade. Another blade's leading edge bore a gouge that was geometrically similar in appearance to a chop-like mark in the engine crankcase, which was found cracked.

Component Examinations.

The following components were removed from the engine: six fuel nozzles, six fuel lines, the flow divider and the fuel servo. Under Safety Board supervision, these components were examined at Precision Airmotive Corporation, Marysville, Washington. In pertinent part, the components were found impact damaged. Some of the parts were found rusted and/or contaminated with mud. The flow divider's diaphragm was found intact. No evidence of pre-impact malfunction was observed.

Radar Track Data.

The FAA reviewed all radar data from the Sonoma County Airport area around the time of the accident. The FAA indicated that in this location it has only one long-range radar site that covers the area below 5,000 feet. When the recorded radar data was filtered to search for targets within a 10 nm radius around the airport and up to 5,000 feet, the subject airplane was only observed one time on a transponder code of 3311. The target had an invalid Mode C code at that time, with no radar reinforcement.

The approximate distance and bearing from the end of runway 19 at the Sonoma County Airport, to this first radar hit, is 2.3 nm and 261 degrees, magnetic. The approximate distance and bearing from the radar hit to the crash site is 0.6 nm and 042 degrees, magnetic.

Based upon a subsequent examination of the radar data showing all targets, three additional non Mode C transponder (primary) targets were located. The positions of these targets were noted southwest of the airport, at the following times: 0929:22, 0929:58, and 0930:22. The calculated ground speed between these hits and the previously identified Mode C target was, respectively, 75, 131, and 163 knots. (See the radar track plot for additional information.)

ADDITIONAL INFORMATION

The airplane wreckage was released to the owner's assigned recovery agent on October 6, 2000. Component testing was completed on November 6, 2000, and subsequently all components were returned to the recovery agent.

NTSB Probable Cause

the pilot's loss of airplane control due to spatial disorientation. A related factor was the low ceiling.