In previous post we brought out various aspects about PSLV launch flight sequence.
A planned flight sequence for PSLV C17 launch is shown below.
Notice the long 2nd COAST of about 145 seconds between 3rd stage separation and ignition of 4th stage where there is no active force acting from rocket burning but still the rocket rises for 164.6 kms to 189.3 kms even though the inertial velocity has fallen from 7762 m/sec to 7732 m/sec.
Just in is the ISRO release stating that the Countdown for which will span over 53 hours has started today morning.
We will give a small tutorial on the subject of COUNTDOWN shortly.