DJPIL
- the designer must provide for full control deflection unless limited by "pilot effort". There are specified values of pilot forces for each of the controls which can mean, for many aircraft types, that only partial control deflection is designed for at Va.
As you say in many aircraft types that means partial control deflection only at Va.
The standard V/N Diagram is for load factor in the pitching plane only and of course shows the edges of any planes envelope based on its structural design limits and Va at the intersection of the stall limit at max load factor.
The Airbus accident highlighted the complexities of the FARs Part 23 and 25 which designers know well but many pilots do not.
Here in the States after the accident and the investigation there were many good articles in the pilot magazines explaining in detail the basic point I was trying to make which was that full control deflection of the aileron and or rudder at or even below Va down to some given speed will very possibly lead to a structural failure. This came as a big shock to many pilots including extremely experienced airline veterans who were unaware of this fact.
Sorry I have not recently read those FAR paras applicable.