MASH - Metallurgical Assessment of Standard Hardware

EASA.2012/2

Standard fasteners are widely used on fixed wing aircraft, rotorcraft, engines, propeller attachments and appliances certified by the Agency. The assumptions made during certification rely on adherence to the certified standard. Deviations from the standard may result in unexpected failure of the fastener with consequences at the aircraft level. /p>

Within the last few years an accumulation of failed standard fasteners (nuts and bolts) in aviation has been observed (refer to EASA Safety Information Bulletin 2012-06). The failures occurring in high strength steel fasteners may happen immediately after installation or in a worst case after only a few flight cycles. This unexpected failure of the fasteners may have severe consequences at the aircraft level when used in critical installations./p>

The intent of the present research project MASH (Material Analysis of Standard Hardware), is to verify if a particular set of European manufactured fasteners adheres to its declared standard.