I'm intimately familiar with the cnt tanks on the F28. The stupid little snaps that are just out of arms reach. BAE146 cnt tank feels like you are lying on your head as you go in, but had ok room inside. 727-100 cnt tank will kill someone if it hasn't already. The access hole is too small, and is half blocked by the aircon duct. And I hate to lace the tanks. I rather F28 snaps, just wish I had longer arms. C130 Bladder tanks aren't bad, lots of room. I came close to death in a 737-200 wing tank trying to get to the MLG casting. I got stuck, had my light break, and my mask got a leak. My manager told me to go in through the wing root access, I told him I wanted to go in through the centre tank access, but he didn't want to have the A/C defueled. He knew best. Ha Ha. Ended up doing it my way, because I refused to do it any other way. I also once got my head wedged between some ribs in the outbrd tank of a C130, and had to get a couple of guys to pull me out.