Hi t-stick, sorry to hear about your problems with UC. I'm not in the aviation industry but the general comments on UC above are all very helpful.
I had severe UC flare-ups in 2006, but (touch wood) since then have been pretty stable. I am taking Azathioprine and Asacol on a daily basis which are keeping things settled. It has been useful to change my lifestyle too, ie. I drink less, try to eat a bit more healthy foods and I exercise a lot more.
The steriods were a very effective course of action over a short period of time to calm things down.
As well as the link that pinkpyjama mentioned, it would be useful to check this group out too:
Crohn's and Colitis UK
Also, if you happen to live in North London, the staff at the Gastro Clinic at the Whittington Hospital in Archway were fantastic towards me, so supportive and helpful. If you don't live there, then hopefully your local NHS trust will be as good.
Best of luck to you, and hope things settle down soon (and stay settled).
Cheers, IJM