KayPam
Your French really makes no sense
My spelling, but the translation comes from my niece, a PhD in French linguistics.
Machinbird:
My definition of trim is mine, and it comes from flying aircraft whose Horizontal Stabiliser is fixed. In such a traditional platform, "trim" is accomplished by deflecting a "trim tab", and is used to reduce the need for constant pressure on the yoke. The tab is cranked in to establish a "trimmed" aspect for cruise.
My first flight instructor cautioned against using trim for maneuvering. For obvious reasons, imo, and 447 is a prime example of "runaway" trim.....again, automatic, no pilot input. In fact, once at the stop, it's bias NU prevented Recovery....
AF 447 was in jet upset, out of control, and auto trim cranked in full Nose Up, in and through aerodynamic Stall....once at the stop, the THS didn't budge; it held that full Nose Up "Trim" until Impact with the Sea.
In an exchange with an AE whose employer was at one time Airbus, I got a very frank admission that the THS program was a huge mistake, and needed to be changed....if the recorded data was accurate... these professionals, always with the "caveat", yes?