Accident Details
Probable Cause and Findings
A LOOSE INTAKE MANIFOLD PIPE ON THE AIRPLANE'S ENGINE WHICH RESULTED FROM IMPROPER MAINTENANCE. FACTORS ASSOCIATED WITH THIS ACCIDENT WERE THE BUILDER/PILOT IMPROPERLY INSTALLING THE INTAKE MANIFOLD PIPE AND THE ALTERNATE LANDING AREA'S HIGH VEGETATION.
Aircraft Information
Registered Owner (Historical)
Analysis
On August 12, 1994, at 0900 central daylight time (cdt), a Schrieber-Stitts SA-3B, NX79GJ, registered to Robert L Schrieber of Muscatine, Iowa, and piloted by a private pilot, was substantially damaged during an off airport forced landing. The pilot reported a partial power loss during initial climbout after takeoff. The 14 CFR Part 91 flight was not operating on a flight plan. Visual meteorological conditions prevailed at the time of the accident. The pilot reported no injuries. The flight departed Muscatine, Iowa, at 0855 cdt.
According to the pilot's written statement on NTSB Form 6120.1/2, his airplane's engine experienced a partial loss of power as the airplane passed through 300 to 500 feet above the ground. He said he began a turn to return to the airport when the engine lost more power. He said he could not maintain altitude and chose a gravel road to land on.
The pilot said he lined up on the road for his landing. When the airplane was about 200 feet above the ground, the pilot said he noticed a vehicle coming toward him. He said he changed his landing area to a bean field next to the road. The airplane contacted three foot high soy bean plants just before touch down. The airplane nosed over after touch down according to the pilot.
An on-scene examination of the airplane revealed that the number four intake pipe had not seated properly against the engine's cylinder. The owner's written statement said the "Loose intake tube [caused] number four cylinder to run lean and intake valve to stick open." A Federal Aviation Administration Principal Maintenance Inspector stated, "The number four intake pipe... was removed and it was noted that the intake pipe seating marks in gasket... did not show a firm circumferential impression."
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# CHI94LA295