Originally Posted by z987k
It may not need to be stated in TAS because of reasons I already went over(dumbing it down), but physics dictates that it is in TAS. As in the airplane does not care what your ias is. Ever.
The Vne is what the manufacturer says it is and tests to. If the aircraft mfg. establishes the Vne as 200 KIAS and ensures that the aircraft has required structural and flutter margin at the service ceiling at that speed, then the Vne is in indicated airspeed for that aircraft as stated by the manufacturer.
If structural strength and not flutter margin is the limiting factor for establishing a particular aircraft's Vne, then the Vne would truly be based on indicated airspeed.
It all depends on the air frame and manufacturer.