What is fixture alignment in the civil works?
The direction each base can or foundation points is fixed when it is set. The civil works set it to the survey line and hold it there, because the fixture’s beam follows the can.
Fixture alignment is the direction a fixture’s beam points relative to the runway or taxiway. For an inset light that direction is largely decided when the base can is set and grouted, and for an elevated unit when the foundation and its bolt template are cast. Pilots read these lights along a line, and a beam that is turned away looks dimmer or off-line from the approach it is meant to serve.
It is a civil interface because the civil works set out the centreline, place each can or foundation to its orientation mark, and hold it there while the grout or concrete cures, while the AGL design decides which way each fixture faces, whether it is unidirectional or bidirectional, and any toe-in on curves. The direction is built in once the material sets, so the check is made before the cure as well as after. The manufacturer’s mark or template, and the layout drawing, give the direction.
Setting out, orienting and holding the can or foundation so its direction stays right.
Fitting the fixture on the can and checking its alignment as part of installation.
Frequently Asked Questions
Q1What does fixture alignment mean in the civil works?
It means setting each base can or foundation so its orientation matches the design before it is fixed. The fixture’s beam follows the can, so the civil works set it to the surveyed line, hold it there while the grout or concrete cures, and leave it for the AGL team to verify.
Q2Why is alignment so hard to correct later?
Once a base can is grouted into the pavement or a foundation is cast, its orientation is built in. Changing it can mean breaking out and re-setting the can, so the first check belongs before the grout or concrete cures, with a second after.
Q3What do the civil works provide and what does the AGL design set?
The civil works provide the survey line, the can or foundation set to the orientation mark, and the grout or concrete that holds it. The AGL design sets which way each fixture faces, whether it is unidirectional or bidirectional, and any toe-in on curves.
Q4Is every fixture simply aligned parallel to the centreline?
No. On a straight length the beam is usually parallel to the line, but on curves, at junctions and for stop bars and crossbars the design sets the direction. The orientation mark and the layout drawing decide, not the line alone.
Q5What can move a can out of alignment during the works?
Pressure of wet grout or concrete, a loose can or template, vibration from compaction or traffic, and rotation while the fixture is fitted. Support the can, use the manufacturer’s orientation mark or template, and check before and after the grout cures.
Q6What happens after resurfacing or repairs?
Surface works can bury, wipe out or disturb the orientation marks and the can itself. The marks are re-established from the survey line, and the orientation of each can is rechecked before the fixture is returned to service.
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