Original Date: 10/14/1988
Revision Date: 01/18/2007

Computer Aided Tomography (CAT) scan radiography is being used by Bell Helicopter Textron, Inc. (BHTI) to inspect complex composite parts such as yokes and proprotor grips. CAT scans can be used to determine fiber misalignments and variations induced by the manufacturing process. In addition, they can also be used to find the typical anomalies which occur in composites, such as voids, porosity and delaminations, which can also be found with more conventional inspection methods. This makes a CAT scan an extremely sensitive and versatile diagnostic tool that can aid engineering and manufacturing in both part design and process development.

Initial activity has involved the use of CAT scan facilities available at local hospitals. The 40 KVma output available at these facilities is more than adequate for inspection of composite parts up to four inches thick. Using these facilities, V-22 proprotor grips and sections of the yokes have been inspected. The results were used to modify the manufacturing processes and design in order to minimize marcelling and wrinkling which occur in these thick section parts. The CAT scan will continue to be used as a design and manufacturing process development tool to further enhance product quality rather than an end item inspection method. The information gained from the use of available CAT scan facilities and results are being used to develop a requirements document and specification for the purchase of a CAT scan system by BHTI.

For more information see the Point of Contact for this survey.