NTSB Factual Report

On December 6, 2006, about 1030 Pacific standard time, a Cessna 150G, N3394J, experienced a loss of engine power and the pilot ditched the airplane in Humboldt Bay near Eureka, California. The pilot/owner operated the airplane under the provisions of 14 CFR Part 91. The airplane sustained structural damage to the left wing and fuselage. The private pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed for the local area flight that departed Murray Field Airport (EKA), Eureka, about 1015.

Humboldt Bay Harbor is a recreation and conservation district that is the only deep seawater port on California's North Coast. The airplane came to rest near an oyster farm.

The closest official weather reporting station was located about 10 miles north of the accident site at Arcata Airport (ACV), Arcata/Eureka. The ASOS reported the following METAR data; wind conditions calm; clear skies with a broken cloud layer at 7,000 feet; temperature 14 degrees Celsius; dew point 9 degrees Celsius; and an altimeter setting of 30.06 inches of Mercury.

According to an icing probability chart, the conditions were conducive to serious icing at cruise power.

A witness to the accident was on a boat on Humboldt Bay working in an oyster farm when he observed the accident airplane flying towards him and a coworker. He stated that everyone knows the accident airplane as it normally flies in the area. The airplane was a cause for concern, as this time it was heading towards them in a nose down attitude, which was not a normal configuration for the airplane. The witness reported that the engine was "running very slow and did not sound like it usually did." The propeller was still turning as the airplane impacted the water.

The National Transportation Safety Board investigator-in-charge (IIC) interviewed the pilot. The pilot stated that he had been flying around for about 15 minutes when the "engine started to fade out." He turned on the carburetor heat, but "not soon enough," and the engine quit. He ditched the airplane into Humboldt Bay. The airplane landed left wing low and spun the airplane around before it came to rest. The pilot was able to get himself out of the airplane and was picked up by a nearby boat.

The pilot reported that both fuel tanks each had 1/2 tank of fuel, and his intent was to fly around the area for about an hour before he came back to land and refuel. The airplane holds a Supplemental Type Certificate (STC) for auto fuel.

In the pilot's written report, he reported that the airplane reached an altitude of 900 feet when the rpm's (revolutions per minute) dropped "some." He applied a little carburetor heat, but the rpm's continued to drop more, and then the engine quit. He attempted to restart the engine, and said that it was "turning over," but would not start. He lowered the flaps to 20 degrees and continued attempts to restart the engine. When he as not able to restart the engine, he made a "standard water landing" in about 12 feet of water.

In the section titled RECOMMENDATION (How could this accident have been prevented) of the pilot's written report (NTSB Pilot/Operator Report, Form 6120.1 (rev. 11/2005)), the pilot stated that the accident could have been prevented had he been advised of carburetor icing conditions before takeoff. The weather portion of the report contained incomplete information, with no temperature or dew point information filled out. In the same section, the SOURCE OF WEATHER INFORMATION, METHOD OF BRIEFING, and BRIEFING TYPE/COMPLETION sections were not filled out.

In an interview with a Federal Aviation Administration (FAA) airworthiness inspector, the pilot reported that the engine experienced carburetor icing, and that he pulled the carburetor heat control, but it did not help.

An FAA airworthiness inspector examined the airplane after it had been recovered from Humboldt Bay. During a thorough examination by the FAA inspector, he noted the poor condition in which the airplane was maintained. The FAA inspector opened both fuel caps and noted that each tank was 1/2 full, and the fuel had an odor he associated with auto fuel. He also noted that a placard above the carburetor heat arm stated that it was inoperative. He was not able to determine why the engine quit.

Records located inside the airplane indicated that the last annual inspection had been completed on June 1, 1990. The owner/pilot reported that he performed the maintenance on his airplane. A review of the FAA airframe and power plant (A&P) mechanic database revealed that the pilot did not hold and A&P certificate.

A review of FAA records found that the pilot's last recorded medical certificate was dated March 20, 2000, and no biannual flight review recorded. The pilot voluntarily surrendered his private pilot certificate, as well as, the airplane's airworthiness certificate and data plate to the FAA Oakland, California, Flight Standards District Office (OAK FSDO) on December 11-12, 2006.

NTSB Probable Cause

a loss of engine power due to carburetor icing and the pilot's inadequate preflight planning and decision to operate the airplane in carburetor icing conditions with an inoperative carburetor heat system.