kinsman - how many flying miles did nasa have before they tried to use a D- rings beyond there certified test temp. limits. Equip comes with limits for reasons. If no limits have been established then it should only be used within the routine levels used in testing. Thus, if now required, new limits should be sought, by means test experiments- as is the case for SiO2 levels of safety in the ash. It will take time yes- but for facts on safety rather than deductions - that is what is required. You may be completly correct and it may be totaly safe to fly in the ash now - but that at the moment that can only be assumed and is not proven.