So, these are some of the considerations we take while designing the hull form so that we get
favorable resistance, calm water resistance. Then, after the hull form is designed we go and
do the model test, from model test we extrapolate for full scale and then during trial condition
you compare whether you have got good prediction or not. But this is not enough for us to
draw up a hull form. So, what else we have, how do you know the resistance at the very early
stage, or for a ship for which resistance data is not available, the tank test data is not
available, what methodology do we follow to estimate the resistance if such data is not
available, tank test data is not available? Over the years, over the last, I would say nearly 70,
80 years, a number of ships, a series of ships have been designed and tested.