A maintenance team replacing some sleepers along the Northern Line
When the London Assembly announced it was seeking people's opinions on Tube disruption and overcrowding it did not take long before Londoners made their views perfectly clear.
BBC London's inbox was soon inundated with angry emails. The Jubilee Line, which is suspended or part suspended practically every weekend, came in for particular criticism.
Many of you thought London Underground should offer refunds on Season Tickets because it was not able to provide an adequate service on the 'part-time' line.
One person even said they were considering moving house because the Jubilee Line was making their life such a misery.
The other side of the line
The disruption is often caused by engineering or routine maintenance work, but what actually goes on inside the tunnels when this is the case?
Tube Lines is the company that is responsible for all the maintenance and upgrade work on the Jubilee, Northern and Piccadilly Lines.
It looks after the signalling, track, fleet, lifts and escalators on the three lines, which between them carry two million passengers every day.
"We understand people's frustrations," says Gavin Silvey, a project manager for Tube Lines, just before he begins another night's maintenance work on the Northern Line at Euston Station.
"We know that they are demanding a better service but they can only have that if we do the improvements. So it is a vicious circle."
Gavin has several teams which go out every night doing maintenance work during the window of opportunity between midnight and 4am when the Tube network closes to passengers.
Everyone needs to wear PPE
A typical job, as witnessed by BBC London when we joined Gavin and one of his teams down on the Northern Line, is the replacement of sleepers.
To remove and replace the huge timbers from underneath the track sounds like a simple task but it involves the coordinated work of about a dozen men.
The work can encompass a variety of skills from grouting and concreting to welding and electrical. Everyone is wearing Personal Protective Equipment (PPE) comprised of a high-visibility vest, a hard hat, ear defenders, protective eyewear, midsole boots and a face mask.
The PPE makes it hard to pick out individuals and the group instead takes on a common identity: workers united by a shared purpose. While most of the capital sleeps, it is a scene being replicated across the Tube network each and every night.
We liken the Northern Line to a geriatric. We are nursing a geriatric!
Conditions inside the tunnel are tough and oppressive; it's extremely hot and, when there is drilling to loosen the earth, it is very loud even with the ear defenders on.
Gavin warns that many people who enter the tunnels for the first time find it claustrophobic.
"This is normal routine maintenance and there are many thousands of sleepers across the Tube network. It is a constant battle to maintain them," says Gavin.
"We liken the Northern Line to a geriatric. We are nursing a geriatric!"
Not so Jubilant
Within a couple of hours of completing the work, trains will be carrying thousands of passengers through the tunnel. For the immediate future this part of the Northern Line has been patched up.
However, it is the Jubilee Line, also maintained by Tube Lines, which has come in for the strongest criticism.
Although weekend disruption on the line is nothing new, it has recently affected several high profile concerts at the 02 that has left late-night travellers stranded and re-ignited the row.
Overcrowding & disruption on the Tube
Gavin says Tube Lines has already increased capacity on the Jubilee Line by adding a seventh car to all trains.
He believes that the brand new signalling system upgrade, which is the cause of the much-hated weekend engineering works, is an investment worth making, despite the disruption in the short-term.
In theory, the new signalling will allow trains on the Jubilee Line to run much closer together and reduce waiting times on the platform.
All together, by the time work is completed at the end of the year, Gavin says Tube Lines will have increased capacity on the Jubilee Line by 40% since it took over in 2003.
But will passengers notice an improvement?
"It is very similar to putting an extra lane on the motorway," he says wryly. "Once you have got the extra infrastructure, more people will use it."
PREPARING FOR THE FUTURE
The training centre has indoor tracks where apprentices can learn their skills
Although Tube Lines needs to make sure that its three lines are ready to work every single morning, it would be wrong to suggest that it hasn't also got an eye on the distant future.
Jamie O'Kelly, 20, from East Dagenham, is among the team who had replaced the some of the sleepers on the Northern Line. Jamie is currently in his second year of Tube Lines' award-winning apprenticeship scheme.
Earlier this year, Boris Johnson pledged to create more than 3,000 apprenticeships across the Greater London Authority over the next three years.
"You get to learn and get paid, so it's the best of both worlds," Jamie tells BBC London. "It is theory and hands-on. You see how hard it is for them to work. You don't appreciate all the work that goes on to make the Tube run."
The training centre
Tube Lines runs a hi-tech £10m Training and Skills Centre in Stratford, east London, complete with indoor railway tracks where it can show its apprentices how signalling, repairs and upgrades can be done.
Tube Lines, working closely with Newham College, takes on up to 30 apprentices every year. Each one will cost the cost the company about £100,000 over the four years of the scheme.
THE SKILLS MANAGER
The investment is huge but the outcome is fantastic
Skills & Competence Manager
"For me, it's a commitment to the local community and it's a commitment to people who are leaving school and want a career in engineering," says Steve Norris, the Skills & Competence Manager for the training centre.
"The investment is huge but the outcome, I believe is something like a 97% retention rate, which is fantastic.
You have got someone who you have moulded into an individual, not just their technical skills but their core behaviours and leadership credentials as well."
James Knight, 17, of Dagenham, is an apprentice who earns £14,400 per year.
He says that many of his friends are currently finishing their exams and applying for university places but they are worried if they'll have a job at the end.
In contrast, James is practically guaranteed a job with Tube Lines if he finishes his apprenticeship.
"Everyone said it would be a good challenge. Well, at the moment I am enjoying it."
And what would James say to the angry commuters who can't get home or to work because of line closures and engineering works?
"People always moan about the trains and delays and all that, but now I know the reasons for it and it's a bit more justified."