Aviation Accident Summaries

Aviation Accident Summary CHI95LA230

WYANDOTTE, IN, USA

Aircraft #1

N8599U

CESSNA 172F

Analysis

THE PILOT RATED PASSENGER REPORTED THAT THE ENGINE BEGAN TO 'POP' AND THE ENGINE SPEED DROPPED TO 1,400 RPM. THE PILOT SWITCHED FUEL TANKS AND APPLIED CARBURETOR HEAT, BUT THE ENGINE DID NOT RECOVER. THE AIRPLANE WAS OVER HILLY/FOREST TERRAIN WITH ONLY A SMALL WHEAT FIELD. DURING AN ATTEMPTED FORCED LANDING. THE PILOT MADE A 50 DEGREE TURN TO ALIGN THE AIRPLANE WITH THE FIELD. THE AIRPLANE IMPACTED THE TERRAIN AND SUSTAINED SUBSTANTIAL DAMAGE TO THE FUSELAGE, WINGS, AND EMPENNAGE. A COMPRESSION CHECK REVEALED COMPRESSIONS OF 50, 55, 10, 66, 62, AND 58 POUNDS PER SQUARE INCH IN CYLINDERS ONE THROUGH SIX RESPECTIVELY. DURING THE CHECK OF THE NUMBER THREE CYLINDER, AIR COULD BE HEARD FLOWING INTO THE INTAKE MANIFOLD. EXAMINATION OF THE NUMBER THREE INTAKE VALVE REVEALED 'CONSIDERABLE' CARBON UNDER THE INTAKE VALVE SEAT AND SCRATCHES IN THE VALVE STEM.

Factual Information

On July 22, 1995, at 1010 eastern daylight time, a Cessna 172F, N157JW, sustained substantial damage during a forced landing near Wyandotte, Indiana. The private pilot and one passenger reported minor injuries. The personal flight, conducted under 14 CFR Part 91, departed Coshocton, Ohio at 0720 eastern daylight time, with a planned destination of Tell City, Indiana. Visual meteorological conditions prevailed and no flight plan was filed. During a telephone interview, the pilot rated passenger reported they were cruising at 2,600 feet mean sea level. The engine began to "pop" and the engine speed dropped to 1,400 rpm. The pilot switched fuel tanks. He pulled the carburetor heat to the on position and the engine speed decreased slowly. The engine did not recover. The terrain was hilly forest, with no open fields. The pilot attempted a forced landing in a small wheat field. He made a 50 degree turn to align the airplane with the field. The airplane impacted the terrain sustaining substantial damage to the fuselage, wings, and empennage. The wreckage was examined by a Federal Aviation Administration (FAA) Airworthiness Inspector. He reported no evidence of preimpact airframe malfunction. A compression check revealed compressions of 50, 55, 10, 66, 62, and 58 pounds per square inch on cylinders one through six respectively. During the check of the number three cylinder, air could be heard flowing into the intake manifold. The number three cylinder was removed and examined by an airframe and powerplant mechanic. He reported "considerable" carbon under the intake valve seat and scratches in the valve stem.

Probable Cause and Findings

the number three intake valve became stuck (seized), which resulted in a loss of engine power. The lack of suitable terrain for a forced landing was a related factor.

 

Source: NTSB Aviation Accident Database

Get all the details on your iPhone or iPad with:

Aviation Accidents App

In-Depth Access to Aviation Accident Reports