In message , at 11:26:45 on Fri, 16 Apr
2021, Recliner remarked:
Anna Noyd-Dryver wrote:
Anna Noyd-Dryver wrote:
Recliner wrote:
Marland wrote:
Recliner wrote:
Marland wrote:


There are more up to date ones which would have been a better
choice such
as this one from the cab of an S stock train under test.

https://youtu.be/ZL8xZrY9SeU

Thanks, that was interesting. From the conversation, the 4th rail test
track is 4km long, and includes virtual stations and virtual tunnels. The
train has to do 500 miles (800km) of testing, so a 100 cycles.


One thing that strikes me from the various videos of the old Dalby test
route is that it is mainly straight. As more trains like the S stock get
constructed with full width connections between cars
or even articulations that could be an achilles heel.
The law of sod if you are testing something says it will be the bit that
wasn’t stressed that shows up an unexpected snag.

I know they have test rigs to repeatedly stress those connections to
destruction, with more violent movement in all directions than you'd want
to put a real train through.

Real service often shows up problems which testing hasn't; the latest
example is cracks in the yaw damper mountings of Northern's CAF units.
Several units are out of traffic, the rest being visually checked daily,
and some 319s are apparently being readied for a possible return to
service.

https://twitter.com/garethdennis/status/1382968339870408707?s=21

That looks like a pretty basic flaw that should have been found and fixed
long ago, particularly as it's happened before, in Ireland!

Or similar failure modes on the Comet aircraft. Don't they teach this on
the first week of engineering courses, any more?
--
Roland Perry