SEAM & Forrestfield-Airport Link

Seam Spatial | Mavis Downs Mine


Nothing is more important than accuracy when building the large-scale infrastructure that enables our cities to grow. This was especially true for the Forrestfield-Airport Link, a $1.2 billion undertaking to connect Perth’s eastern suburbs to the airport and city.

With millimetre-precise tunnel breakthroughs required, Webuild and NRW – leaders in the Australian construction sector – needed gyroscope experts to ensure the success of this project.



The Forrestfield-Airport Link represented a significant infrastructure upgrade for Perth’s rail network – creating three new stations at Redcliffe, Airport Central and High Wycombe.

Several surveyors were working on the Forrestfield-Airport Link, although none had experience in operating a gyroscope. Because eight kilometres of the new rail tracks would run through twin-bored tunnels, expertise in surveying gyros was necessary to:

  • accurately identify the directions needed to tunnel, and
  • precisely align rail tracks at station platforms.



SEAM’s experienced surveyor, with over 30 years in the industry, was brought in to handle all gyroscope observations and provide ongoing reports for third-party data analysis. SEAM provided the following support to meet Webuild and NRW’s needs:

Plan and acquire gyroscope observations in a safe and timely manner within the working tunnel environment

Undertake calculations to transform data between the Perth Coastal Grid and MGA coordinate systems

Calibrate and align gyroscope readings to the surface network for precise tunnel breakthroughs

Provide a precision surveying gyroscope (Gyromat 2000) for hire for the duration of the project

This required SEAM’s surveyor to travel to Perth every three months to:

  1. Carry out all gyroscope observations – used for complex adjustment programs
  2. Produce reporting in a timely manner – so that calculations could be used to update the survey network.



    Completed in October 2022, the Airport Line (as it is now known) has had a positive impact on both the community and Perth’s wider economy, including:

    Reduced traffic congestion and more sustainable transport options – with viable alternatives to car travel

    Better transport options and more efficient services – thanks to additional rail capacity in the inner suburbs

    Improved access between the Perth Airport and the city – boosting tourism and supporting growth

    “The fantastic results from the Forrestfield-Airport Link project have solidified SEAM’s reputation as the experts in providing accurate and reliable survey data for complex tunnelling projects.”
    – Mario Fantin, Metals Mining and Gyroscope Expert at SEAM Spatial

    For precise gyroscope and surveying solutions that meet the highest industry standards, trust the experts at SEAM Spatial.