NTSB Factual Report

HISTORY OF FLIGHT

On October 12, 1995, at 1151 eastern daylight time, a Cessna 172M, N70080, collided with the terrain while maneuvering near Norwich, Vermont. The private pilot and front seat passenger were fatally injured, the rear seat passenger received serious injuries. No flight plan was filed. The airplane was destroyed. Visual meteorological conditions prevailed and the flight was conducted under 14 CFR Part 91. The aerial photography flight originated from Rutland State Airport in Rutland, Vermont, and included a brief stop at Lebanon Municipal Airport in Lebanon, New Hampshire to pickup the two passengers/photographers.

The rear seat passenger/photographer reported that the private pilot had been hired to fly the passengers/photographers over a cottage for aerial photography. The rear seat passenger stated that the pilot told the passengers that they would initially fly by the house/cottage at about 500 feet above ground level (AGL) at a reduced airspeed, and then climb to a higher altitude for more pictures. The rear seat passenger described the topography surrounding the cottage as wooded hills surrounded by rising terrain.

The rear seat passenger stated that the pilot had a specially constructed aerial camera, which he allowed the front seat passenger/photographer to use during the aerial photography flight. The rear seat passenger reported that during the low altitude fly by the cottage, he was taking pictures, and had not paid attention to the actions of the pilot or front seat passenger. He stated that after they passed the cottage and he finished taking pictures, his attention came back inside the airplane. He stated that he expected that the engine noise would increase, and the airplane would begin to climb to the higher altitude, as briefed by the pilot. The rear seat passenger reported that when the airplane did not begin he did not hear the engine noise change, he looked outside and became aware of their low altitude. He stated that he yelled to pull up in order to avoid the trees, but he did not noticed any response from the pilot. The rear seat passenger stated that the pilot appeared to be leaning forward as if trying to read something or trying to reach for something. The rear passenger stated that he could not remember any change in the engine noise prior to tree impact.

One witness stated that he was walking through the woods when he heard "...a very loud plane noise...saw a very small plane just above the trees. It passed by overhead...I heard the engine sputter and die, and then I heard [the airplane] crash." Another witness stated that the engine did not sound right, it sounded too loud and was very noisy for a small plane.

PERSONNEL INFORMATION

Examination of flight logbooks and other records revealed that the certificated private pilot had over 1200 hours in single engine land airplanes, and was current in the C-172. He held a current third class medical certificate with limitations that the holder shall wear lenses that correct for distant and near vision while exercising the privileges of his airman certificate. It was also discovered during the course of the investigation that the pilot was operating an aerial photography business without possessing a commercial pilot's license.

AIRCRAFT INFORMATION

The airplane had a current standard airworthiness certificate for normal and utility categories. The airplane's registration was current and maintenance logbooks for the airframe and engine were maintained and no anomalies were noted.

METEOROLOGICAL CONDITONS

A weather observation taken at Lebanon Municipal Airport (located about 10 miles northwest of the accident site) indicated that at the time of the accident the weather was: sky and ceiling were clear with visibility of 20 miles; temperature 72 degrees; dew point 47 degrees; humidity of 44%; winds were calm; and an altimeter setting of 30.03 inches Hg.

WRECKAGE AND IMPACT INFORMATION

The airplane was found inverted and substantially intact. The engine was separated from the firewall and was in a vertical position with the propeller assembly down. Both propeller blades remained attached to the engine and exhibited chordwise scratches. Postaccident investigation revealed no evidence of preimpact mechanical anomaly. Flight control continuity was confirmed. Engine continuity to the accessory gears was established and thumb compression was found on all 4 cylinders. The engine was equipped with an up-draft, float-type, fixed jet carburetor mounted on the bottom of the engine. Postaccident examination revealed that the carburetor was separated from the sump at the throttle body, and was destroyed.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy (Case Number 95-10-14) was performed by Dr. Paul L. Morrow of the Office of the Chief Medical Examiner, 18 East Avenue, Burlington, Vermont, 05401. Toxicological tests conducted by CAMI in Oklahoma City, Oklahoma, did not detect ethanol, cyanide, drugs, or carbon monoxide.

ADDITIONAL INFORMATION

Several Federal Aviation Administration publications and the Lycoming engine operator's manual indicate that under certain atmospheric conditions, ice will form in carburetors. These publications state that, although carburetor icing is most likely with an outside temperature range of 49 degrees Fahrenheit (F) to 60 degrees F, it can occur at temperatures as high as 90 degrees F. They also state that the formation of carburetor ice is more likely when operating the airplane at reduced throttle settings, and that float type carburetors are more prone to carburetor icing than pressure type carburetors. Excerpts from the publications, and a carburetor icing probability chart are appended.

NTSB Probable Cause

loss of engine power for undetermined reason(s), during a low altitude operation. A factor relating to the accident was: the lack of suitable terrain for a forced landing.