BR Class 151

[HSTEd]

So.... Ive been reading around a bit on the Class 151, and have discovered that the supposed weight of a three car unit was only around 95-100t which seems extremely light, almost pacer light in-fact compared to the apparently ~90 tonnes of a two vehicle Class 171 unit.

Is this weight accurate and if so, how was it achieved? Is it merely an artefact of the aluminium bodies or is there some design reason for the low weight (for example not complying to the crash standards now used for DMUs)?
Would such a body design now be useful as part a Pacer replacement design to allow high differential speeds, low track wear and low fuel consumption on rural branch lines?

Also why is it that no-one took one of the two units built into preservation? Surely its an important component of the developmental history of the "second generation" multiple units.

 

[sprinterguy]

The aluminium bodyshells will certainly have had a hand in keeping the weight down, but a total weight of 95-100t isn't notably light for a DMU built twenty five years ago: Steel built class 150 vehicles weigh between 36 and 38 tonnes.

It's just that modern DMUs are carrying around so much more additional on-board clobber like air-conditioning and more extensive electrical systems and higher powered engines that makes them seem decidedly overweight compared to the Sprinter classes.

Neither of the 151s was preserved because once options for commercial use for the units had been exhausted (Purchased by Serco Railtest in the nineties with the intention of converting them to test units but never proceeded with, and then bought for use as spot hire units in 2000 but that idea also never got off the ground), the two units were in a very dilapidated condition (Not having run for a decade) and had suffered heavy vandalism. Given that spares for their unique transmission system would have been very hard to come by, there wasn't going to be a realistic chance that they could be restored to serviceable condition in preservation.

 

[WillPS]

I've read at one stage Nottinghamshire County Council were looking in to buying them for the Robin Hood Line.

They were born at a time when the railway passenger levels had bottomed out, and the emphasis was on cost saving. I expect they could have gone back to MetroCammell to have a more common transmission system fitted (156?), but the problem was there was very little parts commonality with anything - even with a fairly extensive overhaul they'd still be oddities. Considering in turn that the prototype 150s are problem children among the 150 fleet, and all the troubles with the tiny 180 fleet, the 151s didn't really stand a chance.

Did they not end up with Pete Waterman's company?

 

[Yew]

Yeah Notts CC considered them for the RHL, and its a shame they didnt get them, as it could have been a bit of a draw (like the Bubble cars in wales)

 

[WillPS]

Gawd, you can't run mainlines like heritage lines with "interesting" stock purely on the basis of that stock being of itself a draw. The reason Bubbles are used on those 2 lines is because they're cost effective thanks to the massive massive amount of spares from withdrawn members of the class. The amount of custom they receive as a direct result of the heritage unit is absolutely negligible.

Hell, if SWT couldn't make a case for using the 4CIGs any longer over a bloody 158...!