Originally Posted by
rudestuff
Hopefully the philosophy is the same: on a 767 in the old days they had flap maneuver speeds based on weight, basically Vref30 +20, +40, +60 etc. They were blanket speeds designed to cover all eventualities and still provide the 1.3g buffer. (Flap 15 and flap 20 both used the same speed for example).
More modern versions use speed tape display which has an amber band which is a much more dynamic display: the top of which represents the minimum maneuver speed which still provides full protection at 40° bank. It also moves up and down noticeably with speed brake.
According to the FCTM the Flap maneuver speeds are recommended, and the bug should not be set below minimum maneuver speed, so technically you can fly below the Flap maneuver speed as long as you are above the minimum maneuver speed (amber band) - and cognisant that it is dynamic. Very few do.
Thanks for that. Referring to the FCTM, on page 5.7, it seems pretty clear that we need to add flaps before slowing below the
flap speed. I’m just trying to figure out why this is necessary if there’s still a good margin to the 1.3G buffet at the minimum manoeuvring speed.