Rockwell 112 N1148J

Summary

On 16 October 2014 at about 15:29 local time, a Rockwell 112 registered N1148J, operated by Youhanaian Lawrence, was involved in an accident near Gainesville, Georgia, United States. 2 people were on board and 2 died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

16 October 2014 at 15:29

Classification

Accident

Location

Gainesville, Georgia, United States

Nearest airport

Lee Gilmer Memorial Airport (GVL)

Coordinates

34.2700, -83.8372

Aircraft

Rockwell 112

Registration

N1148J

Category

Airplane

Year built

1975

Engines

1

Operator

Youhanaian Lawrence

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Gainesville → Gainesville

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

ERA15FA016

2 people died.

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.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full 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.

Quoted verbatim from the NTSB record.