Len
The dynamics of the situation - Cat A take-off -v- HV Curve - are completely different and it is quite possible that passage through the HV Curve is a necessary part of the Cat A profile.
The certification process for delineating the HV Curve is, I believe, one that is essentially static without the acceleration that characterises a take-off. All Cat A profiles are certified and therefore approved and to achieve that they will have been demonstrated with engine failures at all critical points.
If that profile seems to contradict the HV Curve then I am sure it is only a problem of perception, not a real one.
G.
