Pilot Debrief

ROCKWELL INTERNATIONAL 112 near Gainesville, GA — 2014-10-16

Final reportERA15FA016
Sign in to save
Date
2014-10-16
Location
Gainesville, GA, USA
Airport
GVL
Aircraft
ROCKWELL INTERNATIONAL 112
Registration
N1148J
Category
Airplane
Highest injury
Fatal
Fatalities
2
Phase of flight
Initial climb

Probable cause

The partial loss of engine power due to the undetected blockage of the inlet and outlet ports of the manifold valve by an organic compound of an unknown source.

NTSB narrative

The flight instructor and private pilot were conducting an instructional flight. A witness reported that, when the airplane about 400 ft above the ground, he heard a "surging" sound coming from the engine and observed pitch and roll oscillations occurring; he then lost sight of the airplane. A video provided by the fixed-based operator showed the airplane take off and begin to climb. Shortly after, it recorded a radio call on the common traffic advisory frequency indicating that an emergency existed and that the airplane was returning to the airport. Another witness reported seeing the airplane's landing gear barely clear a building as it flew toward the airport. He added that, as the airplane neared power lines, the airplane pitched up, likely in an attempt to avoid them. The airplane then collided with a telephone pole and unmarked transmission lines, which ruptured the fuel tank, and then struck the ground. A postcrash fire ensued that nearly consumed the cockpit, cabin, and both wings. Examination of the flight controls and heat-damaged engine revealed no evidence of preimpact failures or malfunctions. Examination of the manifold valve revealed that the inlet and outlet ports were blocked to varying degrees. Analysis of the blockage material determined that it was an organic polymer material consistent with polyester; however, the source of the contamination could not be determined. Although the blockages of the inlet and outlet ports precluded postaccident flow testing of the manifold valve, it is likely that the blockages resulted in the surging reported by the witness and the subsequent loss of engine power. The blockages likely would not have created a condition that would have been detectable to the pilots during the pretakeoff engine run-up. Although the fuel vent lines of both wings were found blocked with organic material consistent with insect nest material, the accident flight was very short and, therefore, it is unlikely that these blockages affected the engine operation. The blockages of the fuel vents were located in an area that would not have been visible to the pilots during the preflight inspection of the airplane.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Pilot could have aborted the takeoff after engine surging was first noticed.

NTSB coding

Evidence available

  • Photos
  • 16 docket documents
View NTSB final reportView NTSB docket

Docket documents16

Related mishaps