"Paul Scott" wrote:
"Bruce" wrote in message
.. .
"Paul Scott" wrote:
None of FGW's 2 car DMUs are diesel electric - I'm sure the only diesel
electric units (ie DEMUs) in use in GB are the Voyagers and Meridians.

The latest new small DMUs (the 172s used by LO and Chiltern) aren't diesel
electric either, and have surprisingly gone back to mechanical gearboxes
following the widespread use of hydraulic gearboxes...

Why surprisingly?

The six-speed mechanical gearboxes have much lower power losses than a
two-speed hydraulic transmission using a torque converter. This leads
to significantly improved fuel consumption and lower CO2 emissions.

I'm not surprised myself - but there seem to be many critics who keep
suggesting it'll never work, usually based on what happened about 40 years
go...


.... while their sucking their teeth, sighing and shaking their heads
theatrically as though they know something that they don't.

The motor industry has steadily been abandoning its torque converter
gearboxes over the past decade in the quest for better fuel economy
and lower CO2 emissions. The railway industry needs to catch up.