We've had freight cars derail when running behind new ES44AC engines around curves. Running a passenger car behind the engine is a solution, but I also found that the REA Sensor car will work on at least 060 curves. Anyone have any ideas about this?
I assume you mean Lionel? The problem is the swing of the semi fixed pilots and coupler. Some of my lighter cars do this on O54 curves when behind the engine. I run my heavier and longer cars behind the engine and that resolves it.
Yes, I did mean Lionel. I thought that the limited swing of the pilot just twisted the truck of the freight car right off the rail...but heavier cars resist the derailing? I'll give that a try too. The REA car looks pretty believable behind the engine...but a passenger car with a freight cars is a stretch for me.
Couple a heavy, die-cast, open-top, three-bay hopper from Lionel behind the Lionel ES44AC loco to see if that makes the pilots and coupler move correctly.
I use MTH freight cars that have truck mounted couplers in which the couplers also can move independently of the trucks. This allows them to be coupled directly to the ES44AC and to track fine without derailing.