N82531

HISTORY OF FLIGHT

On July 23, 2010, at 1017 eastern daylight time (edt), a Cessna U206F, N82531, sustained substantial damage when it was ditched in Lake Michigan about 5 miles west of Ludington, Michigan, after a loss of engine power. The airplane was owned and operated by the pilot as a personal flight under 14 Code of Federal Regulations Part 91. It departed the Gratiot Community Airport (AMN), Alma, Michigan, at 0850 and was en route to Rochester International Airport (RST), Rochester, Minnesota. The single-engine airplane was over Lake Michigan at 10,000 feet above mean sea level (msl) when the engine lost power. The pilot reversed course but was unable to reach the shore, and he ditched the airplane. The pilot survived and was rescued by a fishing boat about 38 minutes later. The pilot rated passenger and three other passengers did not survive. Visual meteorological conditions prevailed at the time of the accident. An instrument flight rules (IFR) flight plan was activated.

On July 23, 2010, about 0659, the pilot rated passenger called the Princeton Automated Flight Service Station to obtain a weather brief and to file an IFR flight plan. The briefer informed him that there was an airmen's meteorological information (AIRMET) for IFR conditions for the entire route of flight that was valid until about 1100 - 1400. There was a Convective significant meteorological information (SIGMET) to the south that paralleled the route of flight. The briefer reported that the winds aloft were from 260 degrees at 41 knots at 9,000 feet, and 270 degrees at 35 knots at 12,000 feet. The pilot rated passenger filed the flight plan and identified the flight as a "lifeguard" flight.

The pilot reported that the purpose of the flight was to take one of the passengers to the Mayo Clinic in Rochester, Minnesota, for medical treatments. The flight was a personal flight and was not associated with a charity organization. The patient and his wife were seated in the aft seats, seats 5 and 6. The patient's doctor was sitting in the middle row on the left in seat 3. The pilot was in the left front seat and the pilot rated passenger was in the right front seat, seat 2. The fuel tanks were filled to capacity the night before the flight. The pilot reported that after climbing to 10,000 feet msl, he leaned the fuel mixture to approximately 14 gallons per hour (gph).

The pilot reported that all of the instrument readings were within normal limits as they crossed the shore near Ludington, Michigan. The head winds were about 40 knots "directly on the nose." Near mid-point over the lake (about 24 statute miles from the shoreline), the engine began to misfire and lose power, with the fuel flow dropping to about 11 gph. The pilot attempted to regain power by pushing in the mixture control to full rich but without effect. About 1005, the pilot contacted the Minneapolis Air Route Traffic Control Center (ARTCC) and reported that the airplane was losing power. He reversed course toward the Michigan shoreline. The fuel flow dropped to about 8 gph. The pilot switched fuel tanks and adjusted the mixture control in and out to try to regain power. He attempted to prime the engine but that had no effect. He reported that he turned on the high boost pump and got a short burst of power for about 30 - 45 seconds, but then the engine "failed completely."

The airplane descended through a cloud layer. About 1012, the airplane was about 12 miles from Ludington and about 2,300 feet above mean sea level (msl) and the airplane was still in the clouds. The surface weather at Ludington indicated that the cloud bases were at 1,800 feet msl. The pilot reported that they had a few minutes before water impact after breaking out of the clouds, so he had everyone don and inflate their life vests. Before impact, the pilot unlatched the pilot's door on the left side of the airplane, and he had the front door of the rear cargo door unlatched. The pilot reported that he did not lower the flaps since the cargo doors would not open if the flaps were extended.

The pilot reported that when he ditched the airplane, either the tail or the landing gear hit the water as he pulled up to go over a swell. The airplane pitched forward, flipped over on its back, and began to fill with water. The pilot unbuckled his seat belt and shoulder harness, fell a short distance, pushed the door open, and got out. He reported that the airplane was sinking rapidly. He saw the right seat passenger and the doctor in the water. A wave hit the pilot and when he resurfaced "everything was gone." He kept yelling but got no response. He eventually started to swim toward the shoreline. About 30 minutes later a US Coast Guard helicopter flew over him but they did not spot him. A few minutes later a fishing boat spotted him and rescued him from the water. He was transferred to a Coast Guard vessel and was taken to shore.

Using side scanning sonar, the Michigan State Police Dive Team located the airplane in about 173 feet of water on July 30. The dive team recovered all the bodies, with the last body being recovered on the morning of August 1, 2010.

The airplane was found resting on its main landing gear on the sandy lake bottom. The airframe and engine were separated by the water impact. Both were raised to the surface by a local commercial recovery service on August 1, 2010. The airframe and engine were taken to a local facility where the National Transportation Safety Board (NTSB) conducted its on-site investigation.

PERSONNEL INFORMATION

The 66-year-old pilot held a private pilot certificate with a single-engine land and airplane instrument ratings. He reported that he had 2,660 total flight hours with 1,200 hours in a Cessna 206. He had logged 25 hours of flight time in the last 90 days, and 7 hours in the last 30 days. He held a third-class medical certificate that was issued in November 2008.

The pilot reported that he had flown similar "lifeguard" flights in the airplane with the pilot rated passenger in the past. He reported that the pilot rated passenger performed copilot duties when he flew with him. The pilot rated passenger also owned an airplane. When they flew in the pilot rated passenger's airplane, the accident pilot would perform copilot duties.

The 70-year-old pilot rated passenger held a private pilot certificate with a single-engine land and airplane instrument ratings. He held a third-class medical certificate that was issued on November 17, 2009. He had 2,150 hours of total flight time at the time of his medical examination.

AIRCRAFT INFORMATION

The airplane was a single-engine Cessna U206F, serial number U-206-01734, manufactured in 1972. It was designed to seat six and it had a maximum gross weight of 3,600 pounds. The airplane was equipped with a pilot (left) side door and a clamshell rear door serving the back two rows of seats. The accident airplane had its middle, right seat (Seat 4) removed. The engine was a 300-horsepower Continental IO-520-F3B, serial number 280171R.

Annual Inspections

The airplane's maintenance logbooks indicated that four different inspection authorization (IA) mechanics had conducted the required annual maintenance inspections on the airplane within the last ten years. The logbooks indicated that the same IA mechanic had performed the last three annual maintenance inspections. On September 27, 2007, the IA mechanic performed his first annual maintenance inspection of the airplane. The total airframe time was 3,893.4 hours. His second annual inspection of the airplane was conducted on October 1, 2008, and the airplane had a total time of 3,908.1 hours. The last annual maintenance inspection was conducted on November 5, 2009, and it had a total time of 3,938.0 hours. At the time of the accident, the airplane had flown 7.5 hours since the last inspection and had a total time of 3,945.5 hours.

FAA inspectors interviewed the IA mechanic concerning the annual maintenance inspections he had conducted on the accident airplane. According to the FAA inspectors, the IA mechanic reported that he used the inspection checklists provided by the pilot/owner in order to conduct the annual maintenance inspections. The pilot/owner provided the IA mechanic with the Cessna Service Manual for "Stationair Series, Skywagon 206 Series and Super Skylane Series, 1969 thru 1971." The service manual indicated the items that needed to be inspected during a 50-hour inspection and 100-hour (annual) inspection. In the section of the checklist covering the "Engine Compartment," Item 29 states that the "Fuel-air control unit screen" is required to be checked during every 100-hour inspection. In the section of the checklist covering the "Fuel System," Item 2 states that the "Fuel strainer screen and bowl" is required to be checked during every 100-hour inspection.

The Cessna Service Manual provides the following information about the fuel strainer:

"Section 13-42. FUEL STRAINER DISASSEMBLY. (See figure 13.9.) To disassemble and assemble the strainer, proceed as follows:

a. Turn off fuel selector valve.

b. Disconnect strainer drain tube and remove safety wire, nut, and washer at bottom of filter bowl and remove bowl.

c. Carefully unscrew standpipe and remove.

d. Remove filter screen and gasket. Wash filter screen and bowl in solvent (Federal Specification P-S-661, or equivalent) and dry with compressed air.

e. Using a new gasket between filter screen and top assembly, install screen and standpipe. Tighten standpipe only finger tight.

f. Using all new O-rings, install bowl. Note that step-washer at bottom of bowl is installed so that step washer seats against O-ring. Connect strainer drain tube.

The engine manufacturer's "Operator's Manual for IO-520 Series Aircraft Engines, FAA Approved September 1980," also provided a checklist for 100-hours inspections of the engine. Item 14 of the 100-hour inspection checklist stated: "Fuel Metering Unit Inlet Screen:...