Long "engineerng" train passing thought Thatcham 13/11/2014 about 759

[whole diary]

[BerkshireBugsy]

Whilst waiting for my taxi home last night what I believe was an engineering train headed eastbound through Thatcham. It appeared to comprise of a diesel at either end and then about 30 units most which appeared to be either ballast hoppers and feeders. - is this some sort of track maintanence set?

Just curious

[a-driver]

The only thing I can think of is the HOBC^▸ (High Output Ballast Cleaner), or High Output Ballast Cleaner

http://youtu.be/9PUlsWQQJ9U

[paul7575]

The HOBC^▸ (High Output Ballast Cleaner) is interesting in that just 'cleaning' is quite an oversimplification.   The business end of the machine is in the middle, and what it does is to remove the existing ballast, and sort out the reusable stuff from the damaged, worn and undersized pieces, then top the remainder up with new and then lay it under the track again.   So at its start of work half the hoppers are empty to take spoil, and half are full of the top up material that replaces the spoil.

There's a video here of it working between Basingstoke and Salisbury:

http://www.youtube.com/watch?v=sI_iDUQ4_-A

Paul

[Electric train]

There is a "virtual quarry" at Westbury one of principle ones in south of the country.  PW^▸ (Permanent Way) trains often have to take a scenic route to get to the worksite, partly to ensure they arrive at site in the right configuration and partly so they enter the site from the end the engineer wants it too and they may be operations reasons as well

[BerkshireBugsy]

Thanks guys - that was definately what I saw last night - it was a very impressive sight!

[stuving]

As noted before, HOBC^▸ (High Output Ballast Cleaner) is very long - or at least can be (depending on what "maximum" means) - this is from the Western Route Sectional Appendix:

High Output Ballast Cleaner (HOBC) and Track Relaying
System (TRS) Trains
These trains are authorised to transit between their operating bases and engineering possessions in excess of
the normal route length limits on Western Route provided that a suitable train path has been identified.
The train identification used and maximum lengths (including locomotives) are as follows:
HOBC  6Y11 127 SLUs   811 metres   887 yards   2659 feet
TRS     6Y33 117 SLUs   744 metres   813 yards   2439 feet
The HOBC and TRS may also exceed the maximum permitted single engine load between the locations listed
below on Western Route. In these circumstances the train concerned must operate with a locomotive at each
end. The rear loco is authorised to apply power as directed by the lead driver to assist as required in the
negotiation of inclines between the mileages shown. In these cases both locomotives must be manned as per
Train Company manning agreements and equipped with back to back radios.

The list of track sections where two locomotives are mandatory include a lot more than the usual very steep gradients, and several stretches of main line, so I think it will always have two in practice.

Realtime trains shows no freight working with HOBC's customary ID of 6Y11 through Thatcham on the 13th, and only routine pathed runs with other IDs. The only "heavy" that evening passed at about 19:15.