by "Cé hé sin" (michael-m-mouse)
Published 01/28/2017 at 17:37
by "Cé hé sin" (michael-m-mouse)
Published 01/28/2017 at 17:37
Tags: Trainlopnik
STARS: 1
One like this. In fact this exact one.
Yes, it’s an offroad vehicle. It goes on rails instead.
Today I experimented with letting somebody else do the driving so I spent about half an hour in this. It’s a Class 2800 DMU .
Performance
Goes well enough given that the line has a relatively low limit. Faster than driving though - if my phone app is to be believed it reaches about 110 knh compared to a limit of 100 on the nearby road. Unlike my previous offroad vehicle it uses all three of its gears on the test route as it’s geared for lower speeds. You therefore get to hear a train changing gear twice (at about 50 and 75 kmh) as it accelerates. As it has a hydrodynamic gearbox (or two, to be pedantic) the sound effects are a little unusual compared to your traditional autotragic. The engine slows dramatically, a pause of a couple of seconds follows while torque converters fill and drain and you’re off again. No engine braking (it freewheels instead) so you get periods of silence followed by the engine winding up again as drive is re engaged.
Ride comfort
Quite honestly it’s a bit of a boneshaker on the test route, which might be a combination of branch line and downmarket train.
Creature comforts
Choose the right seat and you get the world’s smallest table. Free wifi, no sockets but then again if nature calls facilities are provided.
Ease of driving
Very easy, as you don’t have to.
Roadholding
As if on rails.
6/10
would go again. It’s actually cheaper and faster to drive taking account of having to change trains.
"Klaus Schmoll" (klausschmoll)
01/28/2017 at 18:07, STARS: 0
Wikipoop is a bit unclear on this. So it’s a full-on diesel, not a diesel-electric which I thought was more common?
"Cé hé sin" (michael-m-mouse)
01/28/2017 at 18:52, STARS: 1
Diesel electric is used with locomotives because it can handle the power and load involved well.
This is a DMU, a diesel multiple unit, and modern ones are usually diesel hydraulic. They use a Voith hydrodynamic transmission for each engine - some or all of the coaches have an engine and therefore a transmission under the floor. The engines are much smaller than those used on locos so there’s no problem in using hydraulic drive. Diesel electric drive is inefficient which is why you don’t have it in your car.
There is an exception and it is used where railways are being electrified and some diesel sections remain. In this case it may suit the train company to use electro diesel units - they normally run on electricity from cables or third rails but carry engines for use at reduced speed on the non-electrified sections. As these trains already carry electric motors the engines are used to generate electricity. Hitachi are supplying
electro diesels
for use in the UK.