Rearwin 8135 NC25545

Summary

On 18 February 2011 at about 16:58 local time, a Rearwin 8135 registered NC25545, operated by Robert L Copeland Trust, was involved in an accident near Casa Grande, Arizona, 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

18 February 2011 at 16:58

Classification

Accident

Location

Casa Grande, Arizona, United States

Coordinates

32.9082, -111.7589

Aircraft

Rearwin 8135

Registration

NC25545

Category

Airplane

Engines

1

Operator

Robert L Copeland Trust

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Eloy → Chandler

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR11LA140

Nobody was injured.

The partial loss of engine power due to the separation of an exhaust valve rocker box as a result of the failure of the rocker box attaching studs.

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

Read the full NTSB narrative

The engine began losing power immediately after takeoff, and the pilot executed a forced landing in a rough, uneven field. The main landing gear sheared off, and the airframe sustained substantial damage. Postaccident examination of the engine determined that the No. 4 cylinder exhaust valve rocker box was detached from the head of the cylinder. Three of the six attaching studs where broken, and the other three studs had pulled out of the head. One of the three studs that had pulled out was rounded off, indicating that it had been loose in the head for some time. The adjacent stud was also rounded off, but not as much, and the final stud had no signs of rounding off. It is likely that the separation of the rocker box resulted in the partial loss of engine power because the exhaust valve for the No. 4 cylinder could no longer open and close properly, which allowed exhaust gases to migrate through the No. 4 cylinder's intake valve and into the induction system.

Quoted verbatim from the NTSB record.