OR,is the ‘lead axle‘ of each truck the one first in the direction of travel of the locomotive?
intersting que: if you think about it, yes, the lead axle is always an outside axle. ie: there is always one axle thats in the front, and i have never seen anything leading without it being an outside axle. like the others have said, the leading axle is the one that passes you first, in the direction of travel. you can only lead in one direction at a time, and one axle will ever be first. as far as outside goes, im sure im not entirely right here, but im thinking this is a shop term. if a truck is being worked on sans locomotive, and you wanted to discern one axle from another, the proper term would be inside and outside axles. ofcourse, im not entirely sure that 'lead' axle would ever apply here axcept to say if the trucks were uni directional. but that would give you 2 lead axles per unit. and this is for SD units (6 axle). on GPs, well lol both axles are outside axles. i have in my travels mostly heard of the axles referred to in numbers. axle 5 would be the center axle on an SD, 5th back from the F mark (denoting front). ofcourse thats trucks on the loco. with them off, thats where im pretty sure inside and outside comes from. as they wouldnt have any other way to tell them apart. just fyi, E units, which are 6 axle, are not all powered axles. the centers are known as 'idlers'. another term to add to inside, outside, and leading. idler axle. very good question i thought.
Lead axle is the one that would run over your foot first if you stood too close, regardless of direction the locomotive is facing. I have never heard the term outside axle.
I think i get where your going with the outside axle.But it's like Jim said the lead axle is the first axle to traverse the rail in the direction of movement.
