Nick Thomas, AZR...
Thanks to you both. Your input is most helpful.
Briefly, I conclude the bogie is rotating about its horizontal plane as a result of a missing stand-off spacer. I do so because the tires are tracking irregularly in a plane which would ordinarily not be active.
Yes the marks were deposited after the rupture. The artifact that describes the shape of the tread cut suggests the tire was still reasonably intact at the site of the strip's insult.
If this contravenes BEA material, I think it worthy of mention..
So there we are.
A very enlightening discussion, and again, thank you.
Cheers
