Hi FE Hoppy,
Funnily enough, as you will have noticed, we are having a discussion on the relative merits of slats and flaps for the WAT-limited take-off case in, of all places, AH&N:
http://www.pprune.org/aviation-histo...ml#post9679119
Quote from FE Hoppy:
"When discussing this with students I always draw a picture of the wing with both high lift devises in all positions and draw chord lines from Slat LE to Flap TE to show the different incidence on a fixed fuselage and then using Vref corrections discuss CL changes at different geometries.
This clearly shows those combinations where additional Slat does not increase Cl but simply changes the Incidence and thus the required attitude for a fixed Alpha."
That seems a very useful way of presenting the subject. But two things on your E170 scenario - where the flaps are stuck in position 1 - remain unclear to me:
1) Is braking not permitted prior to nose-wheel touchdown?
2) Why is it necessary to maintain a speed increment of +35 kt to the Vref (full) regardless of slat position? In effect, slats lower the stalling speed, and (continuing to state the obvious) basic Vapp is normally a function of Vs.
Is (2) to reduce the risk of tail-scrape, due to unfortunate geometry?