"Andrew Robert Breen" wrote in message

In article ,
Recliner wrote:
"Andrew Robert Breen" wrote in message

In article
,
wrote:

Why are new trains so much heavier? All they have over the old ones
is better crash protection and air con. Would those really make
that much difference to the overall weight? I can imagine it
adding on a few tons but not the huge excess we see in new stock.

Why would you imagine that: consider that the typical weight of a
family
car has close on doubled over the last 35 years - almost all due to
crash protection (with some down to NVH supression and some to a/c
and such). The weight growth of trains looks very modest by
comparison.

Except that they've also (in some cases) switched to aluminium
monocoque construnction, which should make them lighter, just as it
has in cars such as the Jaguar XJ and XK. I have an XJ, and although
it's much bigger and has more gizmos than my previous BMW, it's also
a fair but lighter, and gets away with a smaller engine without loss
of performance. But the aluminium trains are heavier and use more
power than their steel predecessors.

Hmmm..

1968 Jaguar XJ6 4.2: weight 1537 kg.

2008 Jaguar XJ-R: 1659 kg.

Much less of a difference than with the F*rds (much less of a
difference in NVH too, I'd suspect), but in spite of the XK
boat-anchor in the old Jag and the new 'un's alloy structure, the
old'un is still lighter.

So: the aluminium cars are heavier and use more power than their steel
predecessors...

Hardly -- if you're going to use the original 1968 car as the benchmark,
you can't compare it with the current XJR, which is a much faster car.
I'd expect the current 3 litre XJ to be both faster and lighter than the
original 4.2 litre XJ6 from 40 years ago. And that's before you consider
all the standard kit a modern Jag has that the old ones didn't (much
more advance, relatively speaking, than trains).