The AS-B-5 is the UACs most advanced startobomber, this aircraft flies higher and faster than a B-52, while carrying a larger payload.
Undoubtedly the largest currently in the stratobomber range. It's a legacy air frame, but raw speed and sheer size on its side, the SB-16 carries the largest payload of all the stratobombers.
The UACs most recent fully operational stratobomber. Its slow and big, but compensates with a reinforced air frame and a large number built in redundancy systems.
Currently the only recent commercially available stratobomber. The worthy predecessor to the SB-17, the SB-7 carriers a smaller payload but can deliver it faster, with similar reliability.
One of the few "sensible" stratobomber designs and subsequently the only true stealth stratobomber available to UAC. It too is slow, but with the radar cross section of a bird, its not an issue.