Oversprayer, you are wrong. It is NOT gravity that will eventually cause the ISS orbit decay. It is indeed drag: drag between the ISS and the very tenuous atmosphere at the ISS's altitude. It gradually, over the years, slows the Station and causes its perigee to lower. If unchecked, eventually the perigee would be low enough such that much greater drag forces do indeed cause the ISS to burn up. That was prevented during the Shuttle years not just by OMS burns, but also by the Russian Zayrya (spelling?) module and Soyuz and Progress spacecraft. But it is NOT gravity. Gravity simply opposes centripital acceleration to keep the ISS in orbit. If Earth was an airless body, the ISS would stay in orbit pretty much forever.

Falcon, no such manned heavylift vehicle exists, NONE!!!! I wish it did, but wishing don't make it so.... (sigh)