Weird engineering train at Derby?

[brianthegiant]

passing by the former Serco yard at Derby, amongst all the test trains, I saw a very unusual carriage,

It had the round top profile of a Mk3 Carriage, but all black no windows.
There is a narrower section in the middle with a flange in the middle, which looks though the 2 sections can be slid apart.

Is this something to do with tunnel maintenance / repair?

 

[swt_passenger]

passing by the former Serco yard at Derby, amongst all the test trains, I saw a very unusual carriage,

It had the round top profile of a Mk3 Carriage, but all black no windows.
There is a narrower section in the middle with a flange in the middle, which looks though the 2 sections can be slid apart.

Is this something to do with tunnel maintenance / repair?

It's the NR Structure Gauging train.

The bit in the middle uses lasers and IR to measure stuff like tunnels and bridges with respect to the track. I expect it does its best work at night...

 

[Schnellzug]

This contraption?

 

[Hydro]

Correct, it's the Structure Gauging Train. Two systems on it, one called Laserflex mounted at non-corridor end of the wagon in a big cylinder uses lasers for measurement, and the other is the older white light system in the middle shown under the calibration frame at RTC in the above picture. Runs with a 31 one end and DBSO at the other, with IR lights and cameras to record video at night. Sometimes runs in formation with an Ultrasonic working.

It does mainly work at night, due to the white light system. I don't think the Laserflex system is dependent on ambient light, but due to the slow speed of testing (50mph) will probably still run at night.

 

[brianthegiant]

ah I see, very interesting, thanks for the responses!

www.youtube.com/watch?v=ypBczqJ7Nv0&NR=1

so the optical kit also explains why some of the yellow carriages are painted black at one end...

 

[truckman060473]

I've seen one of these around 1999 - 2000 it is bloomin eerie I can tell you. I used to watch for Murco / MOD workings or sandite 37's in the night times down my way. When this thing passed the super white light shone down the entire track side with an incredible brightness. Could have sworn I was about to be abducted by aliens!

 

[sprinterguy]

I've seen one of these around 1999 - 2000 it is bloomin eerie I can tell you. I used to watch for Murco / MOD workings or sandite 37's in the night times down my way. When this thing passed the super white light shone down the entire track side with an incredible brightness. Could have sworn I was about to be abducted by aliens!

Glad I'm not the only one who had that thought when the train passed by one night