Kent & East Sussex Railway

I don't think it is as simple as that. For example, the worst riding loco I have ever been on is a GWR 56xx, which had a horrible fore-and-aft surge. But I believe that that is because it was balanced in a way to minimise vertical imbalance (hammer blow), which it did by transferring that to longitudinal. The reason AIUI is because balancing in that way minimised risk when working in areas, such as collieries, liable to subsidence - which sort of suggests that actually it might have been quite kind on the track, at least from a hammer blow perspective!

So I am not sure there is necessarily a correlation between "this loco is rough when experienced from the cab" and "this loco is hard on the track". My hunch is that Austerities ride badly primarily because they have short wheelbase and therefore pitch around on any localised dips that a longer locomotive would ride over more smoothly, but that doesn't necessarily mean they are therefore hard on the track.

I think you really need to understand what are the factors that cause damage to track, and then see which locos have those factors. But I believe it is more complex than a straight relationship that says "because this type of loco is rough riding, it is therefore automatically hard on the track".

Tom

 

And where would you place a Pacer in the table of who wrecks the track (Jointed Flatbottom)
Who will be first with A Skip


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A Pacer is relatively softly sprung, and being a diesel will have little or no hammer blow effect. One of their nicknames is 'nodding donkey' and certainly they bounce over any dropped joints but it's a not a hard hit as such. Probably they worse they do, is the sideways wear on curves due to the long 4 wheelbase (the effects of which can be heard by the squeal on curves! I much prefer driving them in the wet as the rain lubricates the flanges! Mind you one of ours also lubricates the driver at one end as the cab roof leaks! )

"First with a skip?" Don't tempt me!

 

You must come over and "footplate" our Yank tanks sometime. Make an Austerity ride feel like a Rolls Royce! They are hard on the track and the crews.

 

I imagine that both Austerities and S100s are susceptible to 'boxing' due to cylinders ahead of the wheelbase. The S100 would be worse if that is true.
Pat

 

Ah, my comment was insufficiently precise (which would have been wordier and longer). I was only considering 'rough riding for the crew' from motion in the vertical direction, not in the horizontal direction. (I would assume the direction does not make much difference, to the crew; but to the rails, it will.)

I wonder if oscillations in the horizontal direction damage rails (and the tyres on the loco wheels)? I would posit that they could increase surface, frictional effects on both (caused by the tyres 'dragging' a tiny little bit/distance, forward and backward, as they go through their oscillatory cycle), but whether that creates noticeable wear to the rails and tyres, over time, I have no idea. A statistical study of tyre lifetimes on various classes of locos, over time, would be interesting.

Noel