Originally Posted by
18-Wheeler
Perhaps you should talk to some of the Formula One teams - I think it was Renault that showed Airbus how to perform some CFD work about 30 times faster than they could before. And whilst F1 doesn't do a lot of work with stalled aerofoils they do a lot of work on regular airflow and vortex generation and control.
You missed out my subsequent sentence which (typo corrected
) was:
Sometimes its even simpler and cheaper to just flight test something!
That's where the F1 and Scaled sit. F1 teams routinely do a lot of wind tunnel tests (which negates the point of the OP - they are definitely not replacing WT by CFD) and Scaled are very much a prototyping company. Almost no-one above a certain size makes prototypes any more - test airliners are really pre-production aircraft. The cost involved is such that if you're forced into any kind of significant aerodynamic design change once you're in flight test the whole programme is badly in trouble.
There's also an FAA Ac 9or maybe draft AC, I'd have to go digging) on the topic of flight testing for antennae etc., really aimed at STCs, which sets a significantly high bar to the use of CFD to replace flight test, such that flight test is more-or-less mandatory. (The Part 25 regulation in question, 25.251, actually specifically requires flight test as the means of compliance with the reg)