SAE ARP4991A

This SAE Aerospace Recommended Practice (ARP) describes standard methods for restoring damaged core on commercial aircraft sandwich structures. It currently applies to wet lay up repairs only. The methods shall only be used when specified in an approved repair procedure or with the agreement of the Original Equipment Manufacturer (OEM) or regulatory authority. The repair materials shall be defined in the approved repairs referencing these methods.

The purpose of this document is to provide a set of standard methods that may be referenced in repair documents provides by airlines or airframe and engine manufacturers. It is intended that this document be one of a number of ARPs that will cover other aspects of the techniques required to perform composite repairs. This will provide a suite of available repair techniques that are acceptable for use throughout the commercial aircraft industry.