All that’s required is an extra graph to calculate horizontal distance to achieve Vtoss from TDP and then the existing ‘elevated helideck profile without exposure’ (PC2e) graphs could be used to fly PC1. The missing element now is the ability to demonstrate obstacle clearance because you can’t work out where to start using the climb gradient figures for the 1st and 2nd segments . I was asking for this 12 years ago for the same purpose....