Originally Posted by
john_tullamarine
The guy impressed me when he said that he flies the A320 quite happily at 30-35kts above VMO all day
.. but probably displays a lack of certification knowledge and regulatory compliance discipline. I would have been more impressed had his observation been along the lines of "it isn't going to cause a problem if Vmo is exceeded for a short period, but I won't intentionally permit it to occur unless specifically authorised".
I am presuming that the Airbus is aligned with the usual Vmo/Mmo requirements as, for example, in FAR 25.1505 (
https://www.ecfr.gov/cgi-bin/text-id...11505&rgn=div8)
I fear you might have thought that this was some regular joe that didn't care about being 35kts fast. For avoidance of doubt, the guy leading this instructors conference was a well regarded Airbus test-pilot.
He discussed flying the A320 as a test aircraft rather than a certificated aircraft - sitting at that speed for 30mins towards 2hrs for certification purposes. That's a very different situation than commercial ops; so any of your FAA regs go out the window. He explained that Airbus flew at that speed to calculate a regulatory VMO. I recall poorly - as half of it was going well over my simple head, but it was along the lines of that if they can prove the aircraft can recover from a dive where max speed reaches 385kts without damage (VMO+35kts), then via regulatory requirements, that aircraft can be certificated upto 350kts; tested speed -10% or whatever the regulator required - I'm sure the FAA or EASA has buried that requirement far deeper than you have found.
To satisfy the FAA regs, I imagine that they'd need a big sticker saying "Experimental Aircraft" above the door or something as equally pointless to keep the fed from blushing.
I don't know FAA regs but I would have thought something similar would be amongst the rules over there? How is a VMO calculated under FAA regs? 350kts is a nice round number, but I'm pretty sure there is a little more too it than that?!