TBM Eileen completes first historic breakthrough for the Sydney Metro – Western Sydney Airport project

Mega tunnel boring machine (TBM) Eileen has crushed through a wall of rock to arrive at the Sydney Metro Airport Terminal Station site, marking the first tunnel breakthrough for the city-shaping Sydney Metro – Western Sydney Airport project. 

Since launching at Airport Business Park Station site in April 2023, Eileen has worked around the clock to excavate around 112,000 tonnes of rock – enough to fill about 18 Olympic swimming pools. 

The 1,066-tonne mega machine has tunnelled at an average speed of 120 metres per week to build 1.26 kilometres of fully lined tunnel, which completes the first leg of its 5.5-kilometre journey towards Aerotropolis Station. 

It took about five months to dig out about 293,000 tonnes of rock (about 48 Olympic swimming pools) to build the 25-metre-deep Airport Terminal Station box to prepare for TBM Eileen’s arrival.

The huge machine will now traverse the station box before being relaunched to tunnel under the future Western Sydney International Airport, with the TBM expected to arrive at the Aerotropolis Station site in 2024. 

A total of four TBMs will build the twin metro tunnels for the Sydney Metro – Western Sydney Airport line, with three TBMs already in the ground.  

The Sydney Metro – Western Sydney Airport line will be operational when the Western Sydney International Airport opens for passenger services.