has anyone had the same problem, I low the sensitivity to the lowest and it still is very on stable

I think he means "unstable"

yes, that what I was try to say. any help.

Rastajune,First, I understand that English is most likely not your first language. That's okay. Can you be more specific with your question? Is this the Project Mach 2 Concorde from FSFrance? Describe how you fly it, since the Concorde has to be flown a certain way. For example: Do you fly with the visor up or down? Do you fly at Mach 2 below the recommended altitude of FL550?In my limited experience, I've found that the Concorde can be unforgiving if procedures aren't followed. Post in your native language if you can be more descriptive and comfortable. Between Babelfish and the many bilingual members here, I'm sure we can figure it out. :)Cheers!JonKATL

Do you fly at Mach 2 below the recommended altitude of FL550?Can't say I've ever seen that recommendation in any of the volumes of flying manuals for Concorde.I would recommend the one at flightsim.com by Paul Varn. Andrew

Andrew,Poor choice of words on my part. In my own limited experience, I've found that supersonic speeds in the Concorde below 50,000 seems to net me Center of Gravity and Overspeed warnings, which may or may not be the cause for it to roll side to side while in straight flight. Once I'm up to altitude, that clears up. Also, I've found on initial descent while still at mach 1-plus, the aircraft tends to porpoise while trying to find a good descent attitude.This may be a case of my own misunderstanding of how to fly it. :-lolThanks for the heads up on that guide!Cheers,JonKATL

No worries Jon :-) It's quite hard to simulate (design) this aircraft in FS. The CG doesn't seem to have any effect on how the aircraft flies - you just get a warning light. Also MS modelled the fuel pump system completely wrong, which doesn't help! :-rollThe autopilot in FS is very basic/general, and many of the AFCS modes on the aircraft will actually aid the pilot in flying it. The thing I found with the PM2 airfile was that in order to get the correct fuel consumption, they had modelled low N1/2, and a high FF - where it should almost be the other way around.I say almost: it burns around 7T of fuel an hour in normal idle on the ground ;) Due to this and some other factors, I found it very hard to follow through the checklist with this air-file, which requires the crew to check and set different parameters for different areas of flight, which were just not attainable with their model. Andrew