Beechcraft 23 N7941L

Summary

On 4 June 2020 at about 14:55 local time, a Beechcraft 23 registered N7941L was involved in an accident near Cleburne, Texas, 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

4 June 2020 at 14:55

Classification

Accident

Location

Cleburne, Texas, United States

Coordinates

32.3022, -97.5367

Aircraft

Beechcraft 23

Registration

N7941L

Category

Airplane

Year built

1966

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Cleburne → Cleburne

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CEN20LA211

Nobody was injured.

The total loss of engine power due to metal fatigue failure of the No. 1 cylinder wall.  

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

Read the full NTSB narrative

The private pilot departed on a local flight and had flown for “several” minutes when the oil pressure began decreasing. The pilot elected to return to the departure airport. As he continued on his return, the engine started “shaking” and subsequently stopped. He performed a forced landing on a curving gravel road and subsequently departed the road and impacted bushes and a tree, resulting in substantial damage to the airplane’s right wing. A postimpact examination of the engine revealed the No. 1 cylinder head was separated and the piston exposed. Further examination revealed fatigue cracking through the cylinder wall. The failure initiation was a through-wall crack located on the exhaust side of the cylinder. A review of the airplane logbook revealed debris was found under the oil pressure relief valve seat 4 years prior to the accident, which “caused the oil pressure gage to read zero.” Further review showed that the oil pressure relief valve had been removed, cleaned, and reinstalled 8 months before the accident and that, 3 weeks prior to the accident, the oil pressure relief valve seat was honed, and a new plunger was installed. It is likely the separation of the No. 1 cylinder head was a result of metal fatigue, which in turn, resulted in the complete failure of the engine.

Quoted verbatim from the NTSB record.