Failure Analysis of a Cracked CH-47 Swashplate Rotating Ring, S/N BCW-1379
Abstract
The U.S. Aviation and Missile Command sent the U.S. Army Research Laboratory s Weapons and Materials Research Directorate three swashplate rotating rings from the CH-47 helicopter for investigation. The components were examined due to the presence of cracks found during routine overhaul. These cracks were on and adjacent to the bearing retention shoulder. One of these rotating rings, S/N BCW-1379, was included for a detailed failure analysis to determine the cause of the cracking. This component was QDR exhibit number W45N7V-04-0307. The components were required to be forged from aluminum alloy 2014-T6. The focus of this investigation, BCW-1379, was characterized by nondestructive inspection, chemical analysis, optical microscopy, scanning electron microscopy, and mechanical testing. The holes of the rotating ring were numbered 0 36 around the perimeter, consistent with the convention of the MELRs from Boeing helicopters.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2006
- Accession Number
- ADA455914
Entities
People
- Russell Yocum
- Scott M. Grendahl
Organizations
- United States Army Research Laboratory