[r9etb]

Columbia, especially, was way overdesigned, structurally. That's why it could have never reached the ISS. It was too heavy.

Of course you mean that it was too heavy to carry full-sized ISS components up to the ISS orbit. I'm pretty sure it flew above ISS altitudes on several missions.

[snopercod]

Of course you mean that it was too heavy to carry full-sized ISS components up to the ISS orbit.

You are correct. But don't forget the 30% penalty to reach the 51 degree orbit. Columbia's maximum payload capacity to a standard orbit is 52,500 lbs. to the best of my knowledge.

I believe, but am not sure, that that figure includes the weight of passengers, expendables, and OMS/RCS fuel as well as the junk in the trunk.