VV wrote:There are other reasons why you fly an aircraft not following the plan. The usual reason is when a very annoying CEO of an airline keeps saying, "What the cruise performance of the aircraft after 200 hours of flight you must know it?" Despite the fact there are dedicated flight for the NAMS (or cruise performance tests), some people are not patient to wait. Unfortunately you cannot always say, "Go play around else where, we have things to do here."
Customers can be so irritating, but without them, there wouldn't be any testing or new models. Reminds me of Yes Minister, and the UK's most administratively efficient hospital, with no patients.
Remember behind the scenes, the Boeing sales team, are trying to firm customers to specific milestone payments, on specific dates, on specific aircraft, from specific tranches. Hard to do with just modeled performance. Well not difficult, but customers will build in more penalties and exit opportunities, the more fluid the performance promises, if you can get them to execute at all. And where WB aircraft especially are concerned, the financiers have become as concerned with performance as their customers, so the customer may say yes, and the financiers no, not until we see the numbers.
Presumably Boeing's most annoying CEO's are the majority of current X customers. Airbus would be keen to switch X orders to A350 orders, if Boeing's X sales and engineering teams are too busy building and testing new aircraft to pause their diaries.