Viguie G/Viguie M LANCAIR LEGACY N550AC

Summary

On 18 October 2014 at about 23:30 local time, a Viguie G/Viguie M LANCAIR LEGACY registered N550AC, operated by Crawford Alan R, was involved in an accident near Livingston, Texas, United States. One person was on board and one was seriously injured. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

18 October 2014 at 23:30

Classification

Accident

Location

Livingston, Texas, United States

Coordinates

30.9667, -94.0719

Aircraft

Viguie G/Viguie M LANCAIR LEGACY

Registration

N550AC

Category

Airplane

Year built

2008

Engines

1

Operator

Crawford Alan R

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Jasper → Buchanan Dam

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

CEN15LA018

1 person was seriously injured.

A catastrophic and uncontained engine failure due to oil starvation. Contributing to the accident was the missing No. 3 cylinder intake rocker cover for reasons that could not be determined based on the available evidence.

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

Read the full NTSB narrative

The pilot reported that he was returning from an air race competition and that, about 15 minutes into the flight, he heard a "thump" and thought the airplane had struck a bird. The pilot then heard a second "thump" along with a "rattle and vibration," so he found a place to make a forced landing. While preparing to land, he heard an "explosion" and then saw flames by his left foot and black smoke fill the cockpit. The pilot made a forced landing to a field and exited the airplane before it was destroyed by fire. Postaccident examination of the engine revealed that the No. 3 cylinder's exhaust rocker cover was present but that it was only installed on the cylinder by one screw. The other four screws were missing. The No. 3 cylinder's intake rocker cover and aft rocker arm bolt were missing. The forward rocker arm bolt was installed but loose, and visible rubbing was observed on the boss where the missing bolt was supposed to be installed. According to the engine manufacturer, if a rocker cover is not installed, the engine will port out most of its oil is several minutes. Therefore, the missing rocker cover likely resulted in the engine losing a significant amount of oil during the flight, which led to a catastrophic and uncontained engine failure. It is also likely that, when the crankcase was breached, the fuel lines and the electronic fuel transducer were compromised, which resulted in the subsequent in-flight fire. The No. 3 cylinder intake rocker cover was not located at the accident site, and the pilot reported that he did not know why the rocker cover and aft rocker arm bolt were not installed or why the exhaust rocker cover was only partially installed. He said that the engine performed great during the air race and that he did not perform engine maintenance after the race.

Quoted verbatim from the NTSB record.