Originally Posted by
Wizofoz
In a word, No!!
I'm not sure where you got the VMCA-Vs relationship. The two have no connection to each other. VMCA is dependent on the amount of assymetric thrust present in an engine-fail situation vs the effectivness of the rudder, whilst Vs is dependent on the wings ability to create lift. Changing one has no direct effect on the other.
There IS a regulatory requirement which links the two, but there's, as you say, no technical direct connection.
Originally Posted by FAR25.149
(c) VMC may not exceed 1.2 VS with--
(1) Maximum available takeoff power or thrust on the engines;
(2) The most unfavorable center of gravity;
(3) The airplane trimmed for takeoff;
(4) The maximum sea level takeoff weight (or any lesser weight necessary to
show VMC);
(5) The airplane in the most critical takeoff configuration existing along
the flight path after the airplane becomes airborne, except with the landing
gear retracted;
(6) The airplane airborne and the ground effect negligible; and
(7) If applicable, the propeller of the inoperative engine--
(i) Windmilling;
(ii) In the most probable position for the specific design of the propeller
control; or
(iii) Feathered, if the airplane has an automatic feathering device
acceptable for showing compliance with the climb requirements of Sec. 25.121.
With the appropriate caveats regarding the amendment level of a given regulation