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Mason Land Surveys has extensive knowledge and experience of providing survey solutions to airport operators and their contractors. The unique security and operating conditions present at airports provide daily challenges to which Mason are fully accustomed.
As a BAA Preferred Supplier for land surveying services since 1997; Mason have been involved in many major development projects at Heathrow, Gatwick and other BAA airports, including T5 at Heathrow.
Mason has also provided surveys of Ministry of Defence bases and non-BAA airports, both in the UK and overseas. Surveys have been completed at RAF Brawdy, RAE (Royal Aircraft Establishment) West Freugh, RAFC (Royal Air Force College) Cranwell, RAF Barkston Heath and HM Garrison Dhekelia.
Many Mason staff hold suitable passes for working airside and a significant number also hold airside driving permits. Mason vehicles are clearly liveried and are suitably equipped and insured for working on and around airports. Mason complete more than 100 airport related projects per year at Heathrow alone.
Mason Land Surveys are involved with a wide variety of tasks related to airport activities:
Surveying airport infrastructure
Often working at night, Mason staff are routinely involved with airport infrastructure survey projects. At ground level this involves surveying buildings, stands, taxiways, roads, runways, fuel farms, car parks and grassed areas.
Control is established and normally coordinated to a local (airport) grid. Detail is captured using the latest high precision total stations and GPS units. Data is rigorously QA checked before being passed to the customer in the requested digital format.
Such topographical surveys extend above ground to surveying roof top pipe work and other service infrastructure, often prior to construction or engineering work. Below ground features are also addressed with trained staff conducting underground service tracing for airside and land side projects.
In addition to ground survey, Mason provides data capture services from aerial photography. With one of the best equipped photogrammetric labs in the UK, Mason are able to capture detail and create orthophotos of airports and surrounding areas.
Mason surveyors equipped with high precision GPS units will attend overnight runway inspections with engineers to quickly capture the location of features identified for remedial work.
Obstruction survey
Mason has completed numerous obstruction surveys for civilian and military airports in the UK and abroad. Utilising GIS & CAD base mapping; areas to be surveyed are identified according to the customer’s specifications. Surveys of potential obstructions are normally completed using the latest GPS receivers combined with laser range finding binoculars to accurately record both position and height.
Surveys are conducted to Civil Aviation Procedures (CAP) 168 and 232 specification. Recent surveys have been completed for Heathrow, Leeds-Bradford and Stansted airports.
Ground movement monitoring
Mason has a great deal of experience of monitoring surface ground movement in support of underground tunnelling below airports. A network of check points are established over and around the areas under which tunnelling is taking place. Highly accurate digital levels are used to record the heights of these points over a period of time. Surveys are normally conducted on a daily basis so that any movements can be closely monitored. See the Mason web page on monitoring for more information.
CAAT checking
Mason are able to provide suitably trained staff to conduct independent torsion checks on retaining bolts, following maintenance on runway & taxiway lights.
Airport building & structure surveys
The Measured Building Survey team at Mason are available to survey any airport building or structure. Services provided include the production of floor plans, ceiling plans, sections, asset inventories, location plots and elevations. When necessary advanced techniques, such as Laser Scanning, can be used to capture the location of internal and external features.
Construction survey
Mason Land Surveys are heavily involved with airport construction projects. Amongst many other projects Mason have provided services to engineering teams working on Heathrow Pier 6, Gatwick Pier 2, Heathrow Terminal 3 Arrivals Extension, the new Heathrow Air Traffic Control Tower and at Terminal 5.
Mason regularly provides the following services to airport based construction companies and engineering contractors:
- Provision of control grids & datums
- Setting out
- Topographical surveys
- As built surveys
- Underground service tracing
- Level checks & monitoring
- Dimension checking
- Vertical and horizontal alignment checks
- Position & level monitoring
- Tunnel monitoring
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Mason Land Surveys at Heathrow Pier 6
Heathrow Pier 6 is being redeveloped to accommodate the new Airbus A380. The much larger size of this aircraft means a new style of Pier has to be built. Work is well underway and Mason are at the heart of the action. The project team is comprised of a number of contractors, providing various services. Mason Land Survey are seconded to Mace, the construction leaders, for the provision of surveying services.
Mason provides control for the project on a local Pier 6 grid. Datums have been marked all around the site for the many contractors to measure from. New grid offsets are created on demand; to assist contractors locate the next stage of construction.
As-built surveys are continuously provided as the construction progresses so that Mace and the other team members can check the location and level of the structure elements. Levels are taken within the structure of new services as they are installed, to ensure clearance is maintained.
Steel checks are conducted to check their horizontal and vertical alignment (plumb checks). New installations such as escalators and travelators are surveyed to check their position.
Areas abutting other contractors work on the airfield are surveyed, so that project quantity surveyors can check their figures and schedules. New features are set out to complement work being done by in-house surveyors. Mason work from within the project office so that they can respond as quickly as possible to any demands and form an integral part of the construction team.
Mason Land Surveys & the Heathrow Express Extension
The Heathrow Express rail link has been extended from the central terminals area over to the new Terminal 5 at Heathrow. During the boring and construction of this new tunnel, Mason Land Surveys have been monitoring developments above and below ground.
The tunnel passed under the airfield so careful monitoring of the surface was needed to ensure minimum disturbance was caused to ground areas such as the runway, terminal buildings and aircraft stands. To this end regular nightly level checks were made above the tunnel route to monitor ground movement. To ensure highest accuracy the latest digital levels were used, capable of sub-millimetre level precision.
Below ground the track and other infrastructure were topographically surveyed. The existing Heathrow Express tunnel was closely monitored as the new tunnel neared it to link up. Mason Land Surveys, took nightly measurements to a number of prisms set up along the tunnel length at various heights. Cant and gauge checks were made to the rail tracks. Distance between the gantries and the track were measured. Level checks were made to the track side and the track itself. All these efforts combined to provide a set of figures that could be used to monitor any movement caused by tunnelling and ensure safety on the existing service line.
Mason Land Surveys & the new Heathrow Air Traffic Control Tower
The new Air Traffic Control Tower at Heathrow is now a prominent feature of the airport landscape. The cab section of the tower was prefabricated by Terminal 4 before being moved to its final location in the central terminal area, near to Terminal 3. Over a number of weeks, prefabricated sections were then inserted under the cab forming a steel mast. This method of construction presented a number of survey challenges that Mason were able to meet.
High precision dimensional control was needed to ensure the correct construction of such a complex structure offsite. Mason Land Surveys provided dimensional control services to both the Cab construction site, and checks on the mast sections being machined in Sheffield.
Critically the positions of the top of the tower and the lifting beams had to be accurately monitored as it was raised. Mason provided an automated system using GPS, high precision extensometers and laser technology to generate the position data, which was collected and controlled by the Leica Geosystems GeoMos software. Mason developed an innovative Graphical User Interface to analyse and display a visual representation of the tower’s position and the relative position of the lifting beams in real time.
The dramatic move of the 32metre high cab section across the runway and into position was recently shown on the Channel 5 program Monster Moves. Mason Land Surveys, apart from the Cab construction also set out the base that the cable-stayed tower sits on. These services were provided to the project team on behalf of BAA.
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The new tower being lifted (Photo is copyright of BAA plc)
© Copyright - Mason - 2006
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