Once a rocket has reached its apogee, maximum altitude it will start to turn down into the ground and nothing good can come from that. The rocket could become broken, and what good is investing time into something only for it to break, which is why we develop parachutes. Parachutes slow the rate of descent meaning that when the rocket eventually touches the ground it wont get damaged.
I have the idea of incorporating the parachute into my rocket trajectory simulations, once a rocket reaches apogee Jy = 0, switch to formulas for parachute descent and track the parachutes descent. For those unaware of the study of projectiles in motion, you assume a projectile will be in movement from point a to b, in rockets halfway between a and b the rocket motor will have become spent so the rocket is now in freefall. Which is why I will have a module in my program to accomadate parachutes