Tomei S12 XL N8113N

Summary

On 3 April 2011 at about 19:53 local time, a Tomei S12 XL registered N8113N, operated by Tomei ED J, was involved in an accident near Pleasant Grove, California, United States. One person was on board and one died. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

3 April 2011 at 19:53

Classification

Accident

Location

Pleasant Grove, California, United States

Nearest airport

Private (PVT)

Coordinates

38.8719, -121.4708

Aircraft

Tomei S12 XL

Registration

N8113N

Category

Airplane

Engines

1

Operator

Tomei ED J

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Pleasant Grove → Pleasant Grove

Aircraft damage

Substantial

Weather

IMC

Light

Day

NTSB number

WPR11LA183

1 person died.

The pilot’s failure to allow the airplane’s engine to properly warm up before applying takeoff power, which resulted in the forward cylinder's piston seizing and a subsequent loss of engine power. Also causal was the pilot's failure to maintain an adequate airspeed after the loss of engine power, which resulted in a stall-spin.

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

Read the full NTSB narrative

A pilot-rated witness said that the airplane was airborne within “a couple of minutes” after the engine was started and that, when the airplane reached an altitude of 200 to 300 feet above the ground during climb out, it appeared to slow. The witness said that the airplane then banked left and descended in a spiral until it impacted the ground. Postaccident examination of the engine revealed evidence of abnormal piston wear and cylinder damage, including mechanical scoring and vertical grooves along the forward cylinder walls and piston skirt. A representative of the engine manufacturer reported that the observed cylinder and piston damage was consistent with an in-flight cold seizure of the piston (a condition where the piston seizes within the cylinder). About 17 years before the accident, the engine manufacturer issued a Service Information Letter (SIL) that addressed the potential for such a piston seizure. The SIL stated in part “...Putting a cold engine to hard work without uniform and correct warm up will cause the piston to expand quicker than the cylinder, minimizing clearance and creating piston scuffing and seizure.” It is likely that the pilot did not allow enough time for the engine to warm up before taking off.

Quoted verbatim from the NTSB record.