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Old June 22nd 09, 08:38 PM posted to uk.transport.london
Mr Thant Mr Thant is offline
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Default RAIB Report into DLR Derailment at Last

On 22 June, 13:46, MIG wrote:
Further to the discussion (which I now can't reply to from Google) athttp://groups.google.co.uk/group/uk.transport.london/msg/6d492b8d2fcc...

there is now a RAIB report athttp://www.raib.gov.uk/cms_resources/090622_R162009_Deptford%20Bridge....

Haven't read it properly yet.


I was most surprised to see the train that derailed was also exceeding
a temporary speed restriction at the time. Here's the wonderful Daily
WTFesque story of how this could happen:

"If the speed restriction is required to become more permanent, then
the data is added to an ‘Operational Restrictions List’, [...] a
document stored on a computer and is managed and controlled by a Serco
Docklands systems engineer. He collates the speed restriction data
(as well as other operational restrictions) and enters the data onto
the list."

"[..,] when a change to the operational restrictions list was made, a
paper copy was brought to the control centre and attached to a notice
board at
the side of the room. This was the only copy that existed in the
control room.

"When a re-boot happened, all the data from the operational
restrictions list had to be re-input manually by the control centre
controller. Re- boots were scheduled on a weekly basis for all three
vehicle control computers, and following any software upgrade or work
on the system.

"The entry of the data into the vehicle control computer systems was
usually via a keyboard/mouse interface. It was not easy to check the
data that had been
entered. The capture of the data on the vehicle control computer
monitor screens was difficult; the operational restrictions list data
was shown over many lines and pages of text and was extremely
difficult to extract and check.

"Operational restrictions list data that was being entered by the
control centre controller was not being checked, either by the control
centre controller or by a supervisor in the control centre."

"The majority of re-boots (and hence the re-input of operational
restrictions list data) happened between 03:00 hrs and 04:30 hrs.
This was at one of the busiest times for the control centre
controller. As well as re-entering and checking the operational
restrictions list data, the control centre controller also had to give
instructions to all passenger service agents that were coming on duty
to undertake sweeps, liaise with the depot controller on trains that
were being moved around the system from depots and generally co-
ordinate the railway operations at the start of the morning passenger
service."

--

And that's just one of many borked procedures this incident brought to
light (see paragraphs 214 onwards for a list). I've never seen an RAIB
report that paints an entire company in such a bad light.

U