Certifying an aero vehicle usually means generating your own material allowables and substantiating them by test. Sending coupons to an external test house places a critical part of the programme in someone else's hands and can introduce delays whenever questions arise. Having testing on the same site as our design office allows issues to be addressed as they emerge. An allowable identified during testing can often be reviewed by the design team and resolved within hours rather than through the days or weeks that can result from external interfaces, significantly reducing programme timescales. This close integration is one of the reasons we can offer design, manufacture, test and approval as a single, seamless package.