Unfortunately we do not have A of A meter. I have come to the
conclusion that using the flight manual for specific flap setting and
speeds and wing loading is the way to go.
For example: At a gross of 800 lb and a flap setting of +20 the
optimum speed range is about 5-7 kt, about the same in a 45 deg. bank
with the needed extra speed added for that bank.
But in level cruise the minimum drag has a range from about 70 kt to
95 kt at zero flap and 800 lb gross. You will feel the aft loading
of the airfoil in climb at the Flap handle , but no load in cruise.
Due to friction this " flap handle feel", as an indicator is
unreliable and depending on the airfoil also misleading.
I can speak from practical experience. On my past projects I had to
calculate the speeds for each flap setting as well as wing loading
In case of that airfoil it had a very narrow speed range in each flap
setting to maximize performance but it comes at a cost of having to
pay attention to the flaps to get the most out of each setting.
Udo

On Jul 10, 11:49 am, "Ken Kochanski (KK)"
wrote:
I understand, a wing will perform optimally when the flap is set at
the proper angle for the airspeed ... any mismatch of flap to airspeed
will result in some performance losses vs. the correct setting. Of
course, we have a couple of compromises here ... the flaps are set at
fixed increments and the airspeed varies continuously ... so by
design, you will rarely have the flap and airspeed matched up
perfectly.

I remember seeing a story where one of the German schools modified an
LS-3 with springs, etc. so it automatically put in the correct amount
of flap for the airspeed ... did this result in a measurable
improvement?

Along the same lines, I have heard some pilots say they put the flap
in a position where they feel no pressure ... does this work?

I myself tend to go negative quicker or maintain a negative setting
longer ... then pulling in positive flap ... thinking being too
positive is more costly then too negative ... is this valid?

KK