PB=PV-(+/-d)-(+/- δ )
RB=RV-(+/-d)-(+/- δ )
RilB=RilV-(+/-d)-(+/-dev) la δ va presa sulla prora pPb o Pm
PV=PB+(+/- δ)+ (+/-d)
RV=RB+( +/-δ)+ (+/-d)
RilV=RilB+(+/- δ )+ (+/-d) la δ va presa sulla prora pPb o Pm
Pm= Pv-(+/-d)
RilV =Pv +/- RilP
Pb= Rv-(+/-der)-(+/-sc)-(+/-d)-(+/- δ )
Rv=Pb+(+/- δ )+(+/-d)+(+/-sc)+(+/-der)