Constant force Y is NOT gravity

Could be user error. I have this nice ship flying around and if you let off the thrust you fall down as I set my constant force to be a value of like 4. This is great, but when you start to thrust again you instantly take off straight up again. Its like the its not really gravity as there are no real accelerations to be into account. So how can i make it that while you fall you fall faster and faster...and then
if you thrust (which when thrusting the impulse force polar is set to a direction basted on rotation and then just set to thrust a standard value)...seems like this impulse force polar isnt something we want to use if we want it to be where when you start to thrust it takes a little while for your ship to get going in the up direction again...

anyone can give some insight, i just can't see how to do this.

So the constant force Y works for now, makes your ship "Fall" but you dont fall faster the longer you fall and breaking the fall is so easy any push of the "thrust" button and your on your way again...feels wonky.

Any ideas?