Ian Tindale wrote in message ...
Boltar wrote:

Pressurised air in the brake pipes or tanks moving about?
Sound of the brake pads on rubbing on the discs?
Anything else that can produce a kind of white noise sound really

That's a completely different kind of sound to that described in the
subject.

The only thing I can think of from my days of driving those trains is
the noise made by the current shoes hitting the rail. For example
over a gap in the current rails, when the shoes hit the next section
of the current rail, you do get a strange sound, which may sound like
it's travelling down the train as each shoe hits the rail.

Can't say I've ever noticed it on any other stock! maybe the 96s have
different traction shoes, or the JLE may use a different type of power
rail?

Sorry, that's the only thing I can think of at the moment!