Cessna 150M N714DW

Summary

On 9 May 2017 at about 19:25 local time, a Cessna 150M registered N714DW, operated by Tailwheels Etc., was involved in an accident near Homerville, Georgia, United States. One person was on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

9 May 2017 at 19:25

Classification

Accident

Location

Homerville, Georgia, United States

Coordinates

31.0533, -82.7711

Aircraft

Cessna 150M

Registration

N714DW

Category

Airplane

Year built

1976

Engines

1

Operator

Tailwheels Etc.

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Lake City → Eastman

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ERA17LA176

Nobody was injured.

A total loss of engine power due to inadequate maintenance and inspection of the engine, which resulted in a fatigue crack and subsequent failure of the No. 4 cylinder.

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

Read the full NTSB narrative

The pilot was conducting a cross-country flight when, during cruise at 3,000 ft mean sea level, he heard an unusual sound from the engine and engine power decreased to 1,500 rpm. The pilot unsuccessfully attempted to restore engine power, then light smoke began to enter the cockpit. The pilot subsequently declared an emergency with air traffic control and selected a forced landing site. During touchdown on a soft field, the airplane nosed over and came to rest inverted, resulting in substantial damage. Examination revealed that the engine's No. 4 cylinder had separated about halfway along the cylinder barrel from a fatigue crack that initiated at a cooling fin valley on the exterior surface. The fatigue crack grew around the circumference of the cylinder through approximately 30% of the cross section, and the remaining cross section succumbed to overstress. Once the cylinder fractured, the other components, such as the piston and connecting rod, sustained subsequent damage. Metallographic cross section of the cylinder at and near the fracture revealed the presence of corrosion pits under the remaining paint and primer. While the alloy used in the engine’s cylinders was not necessarily susceptive to pitting, other issues, such as crevice corrosion near an unpainted area or use in salt environments, can lead to similar corrosion features. Corrosion pits can be a common cause of fatigue cracking. Although the accident engine had accrued about 2,249 hours since its most recent major overhaul about 21 years before the accident which exceeded the engine manufacturer's overhaul recommendations of 2,000 operating hours or 12 years in service, whichever occurred first, the No. 4 cylinder had been installed new about 9 years before the accident. However, the presence of pitting corrosion to the extent that it resulted in failure of a cylinder is consistent with inadequate inspection and maintenance of the engine.

Quoted verbatim from the NTSB record.