No, "trim brake" (often spelled incorrectly) is the one people keep using to make themselves sound cool. ;)
Yes, to make it short and sweet, non-articulating trains don't have pivoting wheels. The problem is that even trains like the PTC's on Mean Streak articulate a little (so I've been told, anyway, I've never looked very hard), but the range of motion isn't significant enough to accurately track through turns.
If you want to see very cool articulating trains, check out those on Mike Graham's model coaster site:
http://modelcoasters.cjb.net/ In particular, look at this photo:
http://members.xoom.com/_XMCM/magraha/icecream/construction/12.html The actual wheel assemblies aren't on that picture, but you can see where they attach and how they articulate. The long rod sticking out toward you is the trailer hitch to the next car. It's connected by the universal joint I mentioned. This is precisely how B&M trains work, and you can see why the trains bend over every turn, curve and inversion. This configuration is so flexible that the front car could be pointing to the sky and the back car pointing to the ground.
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Jeff
Webmaster/Admin - CoasterBuzz.com