If the piece of kit is well maintained, the probability will be a very low figure, the impact figure will only be very high figure if the failure means the entire job comes to a standstill and there is no workaround e.g. the hydraulic jacks pushing a new bridge span across the tracks fail completely, now there's a failure you don't want - hundreds of tons of steel dangling across a mainline and no way to pull it back until they are fixed!
If, as has been suggested, it was a crane causing the delay, and there are only 5 such cranes in the country and all are in use at the same time, the cost of the mitigation / contingency plan is so great that you have 2 choices:
1) Don't to the work at all or,
2) Do the work and keep your fingers crossed, when it goes wrong you deal with it as best you can.
The former is not an option, although different ways of doing the work could be looked at. Perhaps a non-Christmas closure and accept the costs of that?
The latter seems naïve but lots of jobs outside railways seem to work on that basis. Many times everything works out fine so you build up an aura of confidence / self-belief or whatever - it hasn't happened in the past, why spend all that money on something that isn't going to happen. Especially if budgets are tight and you are looking to cut costs.
If the piece of kit is well maintained, the probability will be a very low figure, the impact figure will only be very high figure if the failure means the entire job comes to a standstill and there is no workaround e.g. the hydraulic jacks pushing a new bridge span across the tracks fail completely, now there's a failure you don't want - hundreds of tons of steel dangling across a mainline and no way to pull it back until they are fixed!
If, as has been suggested, it was a crane causing the delay, and there are only 5 such cranes in the country and all are in use at the same time, the cost of the mitigation / contingency plan is so great that you have 2 choices:
1) Don't to the work at all or,
2) Do the work and keep your fingers crossed, when it goes wrong you deal with it as best you can.
The former is not an option, although different ways of doing the work could be looked at. Perhaps a non-Christmas closure and accept the costs of that?
The latter seems naïve but lots of jobs outside railways seem to work on that basis. Many times everything works out fine so you build up an aura of confidence / self-belief or whatever - it hasn't happened in the past, why spend all that money on something that isn't going to happen. Especially if budgets are tight and you are looking to cut costs.
**********
I agree with what you say above. An additional problem is the way that successful project delivery may be influenced unduly by the various parties involved. My (extremely simplified) view is as follows
If I look at costs and timescales for job x from different mythical perspectives
1. Transport Secretary - He's got 5 years max before an election, where he
could lose his seat. Voters most important, particularly if those
affected are mainly from his party. The treasury is normally rather
keen on capital projects that carry big numbers as long as it at least
looks like someone has made a decent effort to cost the job and justify
the benefits. Politicians just love grandstanding opportities. Failure of
NR (and TOC's) to implement project successfully can cause early
move to backbenches, loss of seat, unpopularity with fellow MP's. In
event of such failure, a SCAPEGOAT is required by politician, who will
side with public if he has any sense. NR types of all grades only really
of interest if they deliver what he wants and don't foul up.
2. NR Director - costs, timescales and success vital.
Regardless of political persuasion, brownie points for implementing on
time to cost and it works within 5 year timeframe of whichever Govt in
power. ie big bonus, better job or a knighthood beckon. Failure will result
in appointment by Transport Secretary to role of SCAPEGOAT and he
knows it. Has some interest in staff welfare, but probably only in so much
as he knows that failure to show some interest will reap unpleasant
rewards in due course. Unlikely to be keen on unions as they get in the
way and increase project costs if they can.
If estimated costs
-too high (but that's a very subjective thing and he has to decide on
the basis of reasonableness and what he thinks he might get away
with), the project won't get approved by Gov't, or will be descoped.
He likes to have plenty of contingecy in war chest, but as cost is too
high, that's usually one of the early things to be trimmed.
But what if that project is VITAL to lots of other developments???
If actual costs turn out to be much higher than estimated costs,
-he loses his bonus (or possibly job). But he has got the vital job
done and facilitated other dependent gains.
Similarly for timescales,
-estimated timescale too long, Govt will tell director to do it quicker.
If he says he can't, they'll either scrap project, reduce its scope or
replace him with a new director who says he can do it in the cost and
time frame politicans want.
-actual timescale too long, that's an overrun and likely to be major
problems with disgruntled passengers, Minister, knock on effect on
other projects, possible demotion / loss of job in serious cases.
Big project complete failure to successfully implement- bye, bye director.
3. Project Manager
He really is in the middle here. The contractors and NR men with
spades, signals and trains etc want as much time as possible to do
job and the most associated money (with [limited] overtime rather
popular) , His boss the director wants the opposite. The unions and
many of the staff want the status quo in terms of working practices,
which may not suit new ways of working without considerable
'bribes'. If it goes well, he'll likely get big bonuses, promotion, great
CV for future jobs. If it goes tits up, its very bad news. Unlikely to
run a big project again for a long time as the project will be all over
the media and future employers will be aware.
Has to do his master's bidding and likely feels somewhat squeezed,
but is likely much closer to the guys and gals doing the work and
probably rather more appreciative of what they do [or should be].
4. Unions will try very hard to use any proposed deviance from normal
working as a means to ramp up their members rewards in some way.
I suppose its understandable really, but doesn't make life easy when
NR need someone at 01.30 in the morning and there's no negotiated
agreement in place. However, often will help facilitate project
progress as long as not outside confines of existing agreements.
5. Drivers, signallers, civils - project cost irrelevant to them, want as much
time as they can get to do the job so they can be certain of
completing job on time. Generally like to do a good job and are
prepared to work hard for it. Other than overtime and perhaps a
small bonus though, they often don't get significant reward for
project success, so may well be not as enthused as some of the
types higher up the food chain who might benefit more. Used to
working on 'operational' tasks under clearly defined rules, so find
one-off 'project' type working a bit foreign at times.
The above is just an outsiders very simplistic take on the differing kind of mindsets which might occur on an NR project and I'm sure many of you will disagree with many or all of the above. The reason i've shown these possible different perspectives howeever is to show how indirect pressures on major players can be very significant, particularly from above and that not all influences are actually to the benefit of the project, indeed many are towards the individual themselves and their personal situation. The outcome is that well-worked out plans can be challenged with simple questions like "Is that crane really likely to have a x% chance of failing???", there being an implicit 'It's pretty obvious that I think it's too bloody high'. A good Project Manager will review that chance of failure and if the result is the same, stick with it, if not, revise the plans. A bad one lacking confidence, or full of their own importance, may well try to pursuade those who supplied the estimates to come up with a 'new' lower figure to court poularity with his boss or railroad meetings to their viewpoint. I know very little about the workings of the GRIP project system and I am sure there will be some controls and balances to avoid strong 'personalities' riding roughshod over the views of their colleagues, but do they always work?
--- old post above --- --- new post below ---
Yep, at our last management meeting before Crimbo, our CIO took a note of who would be in UK during the holiday weeks if there was a problem. I don't get an on-call allowance or indeed O/T on my grade but would certainly go in and sort out time in lieu etc. later. Isn't that part of and parcel of being a professional engineer?
Yes!

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