>>16703805
>not have a thrust to weight ratio above one until late into the flight.
You don't need TWR > 1 late in the flight actually.
The closer you get to orbital speed the less effective gravitational acceleration you experience, this is why gravitational pull is weaker on the equator from earth's rotation so it's not full one g all the way until you hit orbital speed and then it suddenly transitions straight to 0.
For example when you are at 80% of orbital velocity, you only experience 36% of normal gravitational pull, the rest is canceled by your fraction of orbital speed which can be also described as fictional centrifugal force so your TWR only need to be higher than 0.36