Terry ... I may be reading you wrong but if I take the line off the H stab then that is on the assumption that the stab is set at 0* incidence. That again can give me as a referrence to check decalage same as taking from the wing chord line etc. But I am thinking if I want to ensure that both the H stab and wing incidences are at a certain amount then I will need the FRL as the referrence as the incidence is taken in relations to the FRL but decalage is only the difference between the stab and the wing. Am I correct or am I just not getting it right?