Speedbrakes/Autopilot
With over 8000 hrs on this airplane and having worked in numerous environments with it, I can only say that the speedbrake/overspeed issue only surfaced while in VNAV, fast and in the process of stowing the speedbrakes. As I previously stated, the autopilot calculates a profile to intercept the path and once speedbrakes are retracted, VNAV works to regain the vertical angle, which means increasing speed. The other variable is the fact that this airplane is so clean and once the drag is gone, the airplane wants to accelerate.
I have come to trust this autopilot like no other. I have hit turbulence so strong, crossing the North Pacific, that our flight bags came out of their stowage areas on our sides. The autopilot flew through it like it was supposed to.
One area that does 'irk' me with the speedbrakes, is the initial extension. It seems that the panels seem to 'pop' up from their stowed position and one can feel a very definite-uncomfortable pitch change. I've never really gotten a 'smooth' extension from a fully retracted speedbrake.
How on that, over?