Hi there, I'm working on a Trans-Hypersonic Passenger Aircraft. It is based on the Concorde .air file loosely, However, my aircraft accelerates nicely to well over Mach 4 @ 75k - 80k feet, in fact with the winds in favour, I have 'once' seen her hit Mach 5.03 !!!!! superb! (she can reach London UK to New Zealand in UNDER 5 hrs!!!) The engines are nicely tuned, so there is never any over speeding. & the aircraft is lovely & stable at ALL speeds. The problem is ....I seem to hit a 'wall' when my 'GROUND SPEED' reaches 2666kts.(Sometimes a few kts over, but never under.) - Irrespective of what my Mach & Airspeed are...(even when I reached 5.03, the groundspeed was below 2666, thus making the Mach 5+ possible) The airspeed & Mach all fluctuate according to the wind (as you would expect).... but the aircraft seems to suddenly stop accelerating when I reach the above ground speed. Have I discovered a physically programmed speed limit, actually set in stone by the sim? Or am I experiencing a virtual 'wall' set by some parameters in the .air file? If this is so, does anyone know what params to 'tweak' to overcome the problem? (I use 'AirEd' as my air file editor). In the past I'm POSITIVE I've seen aircraft whiz up well past this ground speed, (Mach 7+ - before the fuel quickly ran out :-) ), when messing with engine thrust & drag etc - so it must be possible?.... (Wish I could remember what .air file it was.) Can anyone help? (I've posted this message in the MS 'aircraft design' forum as well, to get a wider audience / response.) Kind regards. Al

P.S. I'm trying to achieve a 'groundspeed' of 3128kts (3600mph - 1 mile per sec) or greater.Al

BUMP

bump - AGAIN!Doesn't anybody know????Al

Hi,I recommend trying in the section of the forum titled... MSFS Aircraft and Panel Design ForumCheers,Jim

Hi :)I can't get FS planes to go above Mach 3.2 :( ... AirEd seems to limit the Mach Number :( ... over to the appropriate forum I go! :)

Hi JimI have this problem ALREADY posted in the aircraft design forum, & it is getting an equally stale response... :-(Does Anybody who works with aircraft dynamics know???