Starra

(Forgot to respond to this, sorry!)

It's just so Shaped! Even if it went 0.5/3 on launch successes, I have a soft spot in my heart for this funky lil' guy. Something about the length of that wider upper section, paired with the ring of SRBs, transforms the diameter change from offputting to charming.

Background: the Delta III was the intended successor to the Delta II, using a new cryogenic upper stage (which went on to be used on the Delta IV and, with modifications, the SLS launch vehicle). Because liquid hydrogen is so much less dense than kerosene, the fuel tank on this upper stage needed to have much more volume, and it was decided that this would be accomplished by increasing its diameter from the Delta II's 2.44m to a full 4m. Combined with modifying the first-stage fuel tank dimensions to be shorter and fatter, this kept the rocket about the same overall height, allowing Delta II launch facilities to be reused with minimal modification.

Unfortunately, it only flew three times, with two total failures and one partial failure. For the first flight, the guidance system was designed with several assumptions carried over from the Delta II; however, there were some pretty important differences in how the vehicle behaved in flight, and some roll resonances combined with an open-cycle hydraulics system led to the vehicle losing control and being destroyed. The second flight fell victim to an extremely rare failure in the upper stage's RL-10 engine, failing to reach orbit, and the third flight with a dummy payload only barely squeaked into the target orbit range due to another problem with the second stage.

This string of failures made customers quite wary, and with the Delta II going strong and the new Delta IV now being ready, the program was officially ended a few years after the last flight.

It took a few revisions, and it's a combination of several different sources & inspirations (though SushiFur and FlayFuzzDerg are two major such sources of inspiration in terms of my sona's design) - there wasn't really any single driving event or anything ^^;

oooough, favorites are hard... don't really think I have one, sorry ^^;