N72268Cessna 337G · 1973

On May 27, 2010, about 1843 eastern daylight time, a Cessna 337G, N72268, was substantially damaged when it impacted terrain during a forced landing, in High Springs, Florida. The certificated private pilot was not injured. Visual meteorological conditions prevailed for the flight which departed from Valdosta Regional Airport (VLD), Valdosta, Georgia destined for Shady International Airport (FA49), Ocala, Florida. An IFR flight plan was filed for the personal flight conducted under Title 14 Code of Federal Regulations Part 91.

According to the pilot prior to departing VLD he topped off his fuel tanks. After departure he climbed to an altitude of 5,000 feet above mean sea level (msl). While he was in cruise flight at 5,000 feet msl, air traffic control (ATC) cleared him to descend to 2,000 feet. He started to descend, and as the airplane was descending through 3,500 feet msl, the airplane started "acting bad" and "started losing manifold pressure" in both engines and he smelled "oil". He then requested an alternate airfield and was vectored to Camp Kulaqua Field (91FA), High Springs, Florida by ATC. He was unable to make the field but was able to "find a clear area," and make a forced landing.

According to the air traffic controller that was working the flight, after the pilot checked on, he had a discussion with the pilot about his destination. During the discussion, the air traffic controller noticed that the airplane had descended to 4,000 feet msl. As the air traffic controller was about to confirm the airplane's altitude with the pilot, the pilot advised him that he was having a problem and needed to go to the nearest airport. He then directed him to 91FA.

According to Federal Aviation Administration (FAA) records, the pilot held a private pilot certificate with ratings for airplane single-engine-land, multi-engine-land, and instrument airplane. His most recent application for a FAA second-class medical certificate was on May 31, 2008. He reported 6,500 total hours of flight experience on that date.

The accident aircraft was a high wing twin engine airplane of conventional construction. It was powered by two Lycoming IO-360 engines, each producing 210 horsepower. The airplane was built in a push-pull configuration with its engines mounted in the nose and rear of its pod-style fuselage. Twin booms extended aft of the wings to the vertical stabilizers with the rear engine between them. The horizontal stabilizer was aft of the pusher propeller, mounted between and connecting the two booms.

According to FAA records the airplane was manufactured in 1973. According to airplane maintenance records, the airplane's most recent annual inspection was completed on February 26, 2010. At the time of the inspection, it had accumulated 5130.5 total hours of operation.

A weather observation taken about 10 minutes after the accident, at Gainesville Regional Airport (GNV), located approximately 17 nautical miles southeast of the accident site included; wind at 330 degrees at 6 knots, visibility 10 miles, sky clear, temperature 31 degrees C, Dew point 16 degrees C, and an altimeter setting of 29.76 inches of mercury.

Examination of the accident site by an FAA inspector revealed that during the forced landing the airplane's left wing had separated from the fuselage after striking several trees. Both propeller blades of the front engine's propeller were bent aft and the rear engine's propeller was feathered. Fuel was present throughout the accident site.

Examination of the wreckage by NTSB investigators revealed that oil spatter was visible on the underside of the horizontal stabilizer and elevator. Examination of the cockpit revealed that the throttle levers, propeller pitch control levers, and mixture control levers, were full forward. Both fuel selectors were in the right tank position.

Examination of the fuel system revealed no evidence of preimpact malfunction. All fuel filler caps were closed and fastened securely. Fuel samples obtained from the fuel system appeared to be bright, clear, and exhibited no visible contamination. When the fuel samples were applied to coupons containing water-finding paste, the paste did not change color, indicating that water was not present.

Examination of the front engine revealed no evidence of any preimpact malfunctions or anomalies. The front engine's propeller blades were bent aft approximately 6 inches in from the tips. The blade faces in these areas exhibited polishing and span wise scratching. The front engine's crankshaft could be rotated by hand, and continuity was established throughout the drive train. Thumb compression was obtained on all cylinders with the exception of the No.1 cylinder which was impact damaged. Both magnetos exhibited spark at all leads, and fuel was present in the flow divider.

Examination of the rear engine revealed that the engine's crankshaft could not be rotated. Further examination revealed that a hole was present in the top of the engine case, with the end of a connecting rod protruding from it. A portion of one of the connecting rod's bolt was also discovered inside the cowling. Both exhaust manifold and muffler assemblies had remained attached to the engine but a fastener for the number 3 exhaust manifold was missing. Further examination also revealed that the engine's SCAT hoses were worn, partially collapsed in some locations, and disintegrating. The ignition harness shielding was worn through in several places. The mixture control cable was secured to its mounting bracket with a piece of safety wire instead of by the required mounting bolt. The mixture control cable bolt was also loose, its threads were worn excessively, and the drilled hole where the cotter pin was inserted was elongated. Numerous other fasteners and engine bolts were loose and could be rotated by hand, and oil was observed to be weeping from various portions of the engine. Review of photographs of the airplane's parking spot in VLD also exhibited evidence of oil leakage from the rear engine in the form of visible oil on the surface of the asphalt ramp.

The rear engine's dipstick indicated that it contained approximately 8 quarts of oil. When the rear engine's oil sump was drained for examination however, both oil and a translucent light brown colored liquid were captured. The oil was cloudy in appearance, and when the translucent light brown liquid was applied to a coupon containing water finding paste, the paste changed color, indicating that water was present.

Internal examination of the rear engine revealed corrosion and rotational scoring in the oil pump, corrosion in multiple areas of the engine, and thermal damage in the areas of the No.1 and No.2 cylinder's crankshaft journals. Examination of the engine's oil sump revealed the presence of metal fragments, debris, and multiple pieces of the No.1 and No. 2 cylinder's connecting rod bolts, connecting rod caps, and crankshaft bearings.

Test results of an oil sample taken from the rear engine indicated that the oil contained high levels of Iron, Copper, Aluminum, Silicon, and Tin, which was indicative of excessive wear.

Review of maintenance records for the airplane and engines revealed that they were incomplete and that the only entries were for the yearly annual inspections. No entries regarding repairs, alterations, part replacements, oil changes, or preventive maintenance were listed.

Time Between Overhauls

According to Teledyne Continental Motors (TCM) Aircraft Engine Service Information Letter SIL98-9A, the time between o overhaul (TBO) applies only to engines that have been operated and maintained in accordance with TCM's instructions. Engine mounted components and accessories require overhaul at the same hourly and calendar intervals as the engine, unless otherwise specified by the component or accessory manufacturer. An engine’s published TBO also does not mean that every engine will operate the number of hours or years listed without requiring component replacements and unscheduled maintenance events. Non compliance with instructions for continued airworthiness, operational and environmental factors may necessitate repair or replacement of the engine, engine components, and accessories.

Additionally, TCM recommended that along with the engine’s published TBO, in determining the engine’s continued airworthiness, that it be considered whether the engine had been operated regularly or had been in storage, and that gaskets, seals synthetic and natural rubber goods deteriorate over time. Consideration should also be given to environmental corrosion, as corrosion can occur internally and externally on the engine and that this naturally occurring process can inevitably affect continued airworthiness of the engine, and engine mounted components and accessories. For these reasons, TCM recommended that engines be overhauled at least every twelve (12) years, or on accumulation of the operating hours listed for the engine model.

According to the maintenance records, total time in service for the failed rear engine was 2404.3 hours. According to the information contained in SIL98-9A, TBO was 1,500 hours.

Engine Out Procedures

During a telephonic interview when asked about the airplane manufacturer's procedures for a loss of power (engine out procedures), the pilot was unable to articulate them, and when asked about his subsequent actions, the pilot advised that he had not feathered the propellers.

Examination of the airplane had revealed that both throttle levers were full open, both propeller control levers were full increase, the mixture controls were full rich, and the fuel selectors were both selected to the right fuel tank but, according to the airplane manufacturer, in the event of an engine failure, the "ENGINE-OUT DURING FLIGHT" checklist (which is published in the Owner's Manual) should be used by the pilot to determine the inoperative engine and secure it by moving the mixture to idle cutoff, feathering the propeller, turning off the auxiliary fuel pump, turning off the alternator, turning off the ignition switches, turning off the fuel selector valve, and closing the cowl flaps.

Furthermore, a review of Section VI (Operational Data) of the Owner's Manual revealed that if the airplane was configured using the "ENGINE-OUT DURING FLIGHT" checklist, the airplane had sufficient residual performance to continue flight.

Post accident review of ATC data, controller statements, and publicly available documents revealed that even though the accident airplane would not have been able to glide far enough to reach the airport that the air traffic controller was vectoring the pilot to, he would not have been able to land at 91FA as it was no longer an operational airport and had been turned into a privately owned camp and retreat, and a water park existed where the airport used to be.

As a result, in order to improve safety, the FAA took the following actions:

1. FAA personnel re-emphasized to listed airport owners the necessity to keep the FAA informed of any changes to the status of their airports.

2. The FAA's Air Traffic Organization (ATO) verified nationwide that airports listed on the emergency radar vector maps were operational.

These actions were concluded by the FAA on May 25, 2011.