Gracie Virtuali!
I have never experienced it using the "Slew Mode" (as far as I know) but, I will make a few experiments... I do, however, see this on several sceneries and all the AICarriers models but, I assumed it was due to the motion of the carrier model on the waters (a form of "pitching deck"). Thus, I began to wonder if it was Landclass / terrain / scenery elevation "Correction" related; as I have FSGlobal, UTX - USA, Europe & Canada + All of Orbx's FTX AU Packages colliding and, the computer was updating their elevation information constantly, resulting in minor elevation corrections. That was my "theory" and, since you are an expert in these issues, I thought that I would seek your wisdom first...
I have had this issue for a while but, until now, I never though to inquire as to wheather it was a landclass collision with sceneries; or, as you've indicated, something entirely different. Finally, I just happend to read this review on AVSim,
http://www.avsim.com/pages/0809/Aerosoft/AES.htm , and the author just happened to mention:
"A bouncy A330 that I had to fix through trial and error" that it was aircraft related, as well. So, I'll consult him, as well, to see if it is something that can be fixed in the aircraft.cfg files or, perhaps, it could be something (as Mr. "skimmer" mentioned above related to AICarrier module) that magnifies this effect in the game. Either way, I have a better understanding of it and I thank you all for the time and info.
I'll see what I come up with... and post a solution, if it can be found; like I did for the Carriers Launch-Bar/Tailhook enabling and positional corrections in the Aircraft.cfg's, which makes Launches and Recoveries possible for all aircraft in FSX.
Thanks, again, & Ciao!