IAD99LA018

The pilot-in-command departed Wilkes-Barre, Pennsylvania, approximately 2145 in the Cessna 172 destined for Essex, Maryland, 125 nautical miles (straight line) distant. He reported a total of 30 gallons of fuel aboard at departure (20 gallons having been purchased at Wilkes-Barre), and estimated a flight duration of 1.75 hours. According to the aircraft owner's manual, unusable fuel was 2.5 gallons per tank, and the maximum fuel consumption for the O-300-A engine at 2,500 feet above sea level is 12.6 gallons/hour (worst case scenario). Fuel consumption decreases as altitude is increased and/or RPM is decreased. Approaching his destination, the pilot descended from 3,500 feet 1,000 feet, entered the downwind, applied carburetor heat and initiated a left base turn at 700 feet. He reported that RPM dropped off, and unable to reach the airport, he ditched the aircraft in a river under dark night conditions approximately 2330 local. A post crash test run of the engine was inconclusive and approximately 6 gallons of fuel was recovered from within the right wing fuel tank with the remaining fluid from both tanks being water. Temperature/dew point near the time of the accident was 43/30 degrees F. and serious carburetor icing conditions may have existed.

On November 15, 1998, approximately 2330 eastern standard time, a Cessna 172, N5806A, registered to an individual owner and being flown by a private pilot, was substantially damaged when it was intentionally ditched in the Back River, near Essex, Maryland, following a power loss. The pilot and passenger received minor injuries. Visual meteorological dark night conditions prevailed, and a flight plan was not filed. The personal flight was to have been operated under 14 CFR Part 91, and originated from Montreal, Quebec, approximately 1345. The intended destination was the Essex Skypark airport, Essex, Maryland.

The pilot reported that he "cancelled flight following about 10 miles NW of [the] field. Descended from 3,500 ft to 1,500 ft. Entered the pattern at 1,000 ft. on a left hand pattern for runway 34. Turned on carb[uretor] heat and checked [the] fuel tanks and mixture controls. Started [a] left base turn @ 700 IA. As I retarded [the] throttle to bleed off airspeed, RPM's dropped right off. Checked mixture and fuel selector again and found no problems. Then rotated through [the] fuel tank selections without [the] engine coming back on." The pilot then determined that he would not be able to make the airfield and ditched the aircraft.

The aircraft was not recovered from the Back River until November 17th. Following the recovery, it was determined that substantial damage had been incurred and a representative from the Federal Aviation Administration's (FAA) Baltimore Flight Standards District Office (FSDO) examined the aircraft on November 18th.

The inspector reported that, following the aircraft's removal from the river, the engine was examined. The oil was drained and replaced, a small amount of fresh fuel was supplied to the engine, and an "as is" test run was initiated. The inspector reported that although the magnetos had been exposed to water the engine fired, "spitted" and "popped" but would not run smoothly. He also reported that both fuel tanks were drained subsequent to the aircraft's recovery. The left tank yielded only water, whereas the right tank contained both fuel and water. The inspector estimated the fuel quantity in the right tank as 6 gallons.

The aircraft was equipped with two metal fuel tanks, one mounted within each wing. Each tank had a capacity of 21 gallons of which 18.5 gallons were reported by the manufacturer as useable. Either fuel tank could be selected individually, as well as both tanks simultaneously, from the cockpit mounted fuel selector. The engine was supplied fuel from the fuel tanks by means of gravity, and no boost pump or engine driven pump was installed.

The aircraft reportedly departed Montreal and stopped at Watertown, New York, to clear US customs. The sole fuel provider at the Watertown airport reported that there was no record of N5806A acquiring fuel on November 15th, although a record of 12.5 gallons for this registration was noted two days earlier.

According to the fuel provider at the Wilkes-Barre Scranton International airport (Wilkes-Barre, Pennsylvania), N5806A acquired 20.0 gallons of 100 low lead aviation octane fuel late on the evening of November 15th. The pilot reported departing Wilkes-Barre at 2145.

The approximate straight line distances (nautical miles) between the three flight legs conducted on November 15th were measured on a chart and noted below:

Montreal, QB --> Watertown, NY: 135 nm Watertown, NY --> Wilkes-Barre, PA: 161 nm Wilkes-Barre, PA --> Essex, MD: 125 nm

The fuel state of the aircraft upon departure from Montreal was not known. However, the pilot estimated that he had approximately 30 gallons of fuel on board, and anticipated a 1 hour and 45 minute flight to Essex upon departing from Wilkes-Barre. According to the aircraft owner's manual, the maximum fuel consumption for the O-300-A engine at 2,500 feet above sea level is 12.6 gallons/hour (worst case scenario). The pilot's projected fuel burn was not inconsistent with the fuel burn rates for the Continental O-300-A powered Cessna 172 at 2,500 to 5,000 feet above mean sea level, as depicted in ATTACHMENT OM-I.

The outside air temperature at the Baltimore-Washington International airport, located 12 nautical miles west of the accident site, at 2354 local was 43 degrees Fahrenheit and the corresponding dew point was 32 degrees Fahrenheit (refer to ATTACHMENT CI-I "Carburetor Icing Chart").