ASN Wikibase Occurrence # 170512
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can submit corrected information.
| Date: | Thursday 16 October 2014 |
| Time: | 11:29 |
| Type: |  Rockwell Commander 112A |
| Owner/operator: | Youhanaian Lawrence |
| Registration: | N1148J |
| MSN: | 428 |
| Year of manufacture: | 1975 |
| Total airframe hrs: | 3657 hours |
| Engine model: | Lycoming IO-360-C1D6 |
| Fatalities: | Fatalities: 2 / Occupants: 2 |
| Aircraft damage: | Destroyed |
| Category: | Accident |
| Location: | Near Lee Gilmer Memorial Airport (KGVL), Gainesville, GA -
 United States of America
|
| Phase: | Approach |
| Nature: | Training |
| Departure airport: | Gainesville, GA (GVL) |
| Gainesville, GA (GVL) | |
| Investigating agency: | NTSB |
| Confidence Rating: |  Accident investigation report completed and information captured |
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.
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.
Accident investigation:
 |
|
Sources:
NTSB
Location
Revision history:
| Date/time | Contributor | Updates |
|---|---|---|
| 17-Oct-2014 07:15 | Geno | Added |
| 17-Oct-2014 17:33 | harro | Updated [Aircraft type, Registration, Cn, Operator, Total fatalities, Source] |
| 17-Oct-2014 21:19 | Anon. | Updated [Departure airport] |
| 19-Oct-2014 08:20 | reformfaanow | Updated [Location, Narrative] |
| 24-Oct-2014 05:46 | Geno | Updated [Time, Location, Nature, Departure airport, Destination airport, Source, Narrative] |
| 11-Nov-2014 22:16 | Geno | Updated [Total fatalities, Source, Narrative] |
| 21-Dec-2016 19:28 | ASN Update Bot | Updated [Time, Damage, Category, Investigating agency] |
| 30-Nov-2017 19:28 | ASN Update Bot | Updated [Operator, Other fatalities, Departure airport, Destination airport, Source, Narrative] |
Corrections or additions? ... Edit this accident description
The Aviation Safety Network is an exclusive service provided by:
Quick Links:
| ASN Home | Send Correction / Feedback |
| FSF Home | Disclaimer | Copyright |
| Contact Us | Privacy Policy |
| Press / Media |
CONNECT WITH US:
©2024 Flight Safety Foundation