Piper PA-28-180 N7698W

Summary

On 7 August 2011 at about 18:33 local time, a Piper PA-28-180 registered N7698W was involved in an accident near Millsap, Texas, United States. 2 people were 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

7 August 2011 at 18:33

Classification

Accident

Location

Millsap, Texas, United States

Nearest airport

None

Coordinates

32.7756, -98.0561

Aircraft

Piper PA-28-180

Registration

N7698W

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Mineral Wells → Grand Prairie

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CEN11LA555

Nobody was injured.

A sudden loss of engine thrust due to the separation of a propeller blade in cruise flight due to high cycle fatigue.

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

Read the full NTSB narrative

The pilot had just leveled off to cruise flight when the airplane jerked and began to vibrate violently. The pilot secured the engine and made a forced landing on a road. A postaccident examination revealed that an 18-inch section of one of the propeller blades had separated. Metallurgical examination of the remaining blade section revealed striations on the fracture surface consistent with high-cycle fatigue. At least three crack arrest marks were observed, which was consistent with the stopping and starting of the cyclic stresses. The propeller had accumulated 165.73 hours since being overhauled in 2004. The most recent 100-hour inspection was completed about 10 months before the accident. The Federal Aviation Administration issued Airworthiness Directive (AD) 69-09-03 R3 in 1996 to prevent propeller blade tip fatigue failure. The directive required that pilots avoid continuous operation between 2150 and 2350 rpm. The failure mode of the blade was consistent with it operating in the restricted rpm range. Due to the multiple arrest marks found in the examination, the fatigue crack had propagated over multiple flight cycles. It could not be determined when the fatigue crack was initiated.

Quoted verbatim from the NTSB record.