The first tunnel boring machine to dig underneath London has been launched by HS2. 

In total six tunnel boring machines (TBMs) will dig more than 26 miles of tunnels under the capital as part of the huge infrastructure project. 

HS2 CEO Mark Thurston was joined by local teacher Sushila Hirani, after whom one of the tunnel boring machines at the West London site is named, as it begins on its five-mile journey. 

“Sushila” is the fourth of 10 HS2 tunnel boring machines to be launched. 

Later this year a second TBM, named after 18th century astronomer Caroline Herschel, will also be launched from the West London site to build the second of HS2’s twin-bore tunnels towards central London. 

Each weighing more than 2,000 tonnes and measuring 140 metres in length, both TBMs will bore five miles non-stop for 22 months, except Christmas Day and bank holidays, to Greenpark Way in Greenford, where they will be dismantled and lifted from the ground. 

Separately, two other TBMs  will set off towards Greenpark Way from HS2’s Victoria Road site in 2023 to build a further 3.4-mile twin-bore tunnel. 

Together the quartet of TBMs will build 8.4 miles of twin bored tunnels between West Ruislip and the new high speed rail super hub station at Old Oak Common.  

Another 4.5-mile twin-bore tunnel extending from Old Oak Common to Euston will complete HS2’s journey to its London terminus. 

Each TBM is operated by 15 people, working in shifts. A team of around 40 people assembled the TBMs, with 56 companies involved in getting the site ready and machines launched. 

In total the 10 TBMs will create 64 miles of tunnels on HS2 between London and the West Midlands.  

HS2 CEO Mark Thurston said: “The launch of the Tunnel Boring Machines on the longest section of tunnels through London is a significant moment for HS2, and one that demonstrates the momentum that has built behind Britain’s flagship levelling-up project. 

“The construction of 170 miles of new high-speed railway between London and Crewe is now in full swing, supporting 27,000 jobs, nearly 1,000 apprenticeships and contracts for over 2,500 businesses.”  

Local school children from Dairy Meadow Primary School in Southall and Brentside Primary Academy helped name the TBMs after participating in workshops about the tunnelling work. 

The recently launched TBM called Sushila is after local schoolteacher Sushila Hirani, head of department and lead for STEM at Greenford High School. 

The Willow class at Dairy Meadow Primary School in Southall suggested the name due to her inspiring work and passion for getting more women and young people from BAME backgrounds into STEM subjects.   

With a background in product design, Sushila has been a teacher for nearly 30 years. 

Her involvement in local infrastructure and development projects, including the Waterside housing development in Southall, and drive to attract girls into STEM subjects as a path towards engineering at A Level, apprenticeships and degrees, has inspired many in the local area.  

She said: “I was very surprised that the Willow class pupils at Dairy Meadow chose to put my name forward for this honour. When I met the pupils I was very impressed by how much work they had already engaged in relating to design and technology and STEM, led by their teacher Prabhjot Uppal, who is the design technology lead at the school.

“I have always had a passion for industrial design and engineering, and if this event helps young people connect with engineering and inspire them to pursue this path, then my small contribution here has been worthwhile.”  

TBMs Sushila and Caroline will be operated by Skanska Costain STRABAG JV (SCS JV). The machines are manufactured by worldwide TBM specialist Herrenknecht in Germany.    

James Richardson, managing director of Skanska Costain STRABAG JV, added: “Today we start one of the most complex parts of HS2, tunnelling from here at West Ruislip towards Euston beneath one of the busiest cities in the world. 

“The huge team effort has enabled some of the most advanced TBMs ever built to be launched. Our team has brought together world-class skills along with developing many new people to the industry working on this crucial national infrastructure project.”