In this article we review the use of surface marking within airports, common issues and challenges that are faced by either in-house maintenance teams or airport maintenance contractors.
Markings on runways and taxiways are often taken for granted but without them, our airports would be in chaos. These markings are of high importance, they help guide pilots to and from the runway, provide situational awareness, provide the only continuous visual aid and mainly promote safety.
Lack or clear, effective markings can lead to a number of incidents:
- Cause confusion to all airport traffic
- Contribute to an incursion
- Reduce safety
Black borders provide extra contrast for increase visibility during daylight
Glass beads provide high-visibility and reflectivity during daylight
The most important aspect of surface markings is visibility. Markings need to be conspicuous and highly visible especially in low light or bad weather conditions. They are there to reduce confusion and enhance safety.
After outlining the necessity of markings, we now take a look at why they are a challenge and the issues that are associated with them.
1. FAST DETERIORATION:
There are a number of possibilities as to why airfield markings can deteriorate too quickly.
Block colour crazing and wearing down quickly
Black and yellow lines fading, flaking and loss of vibrancy
Firstly, as with any application, preparation is essential. 80% of paint application failures are a result of poor preparation. If there is anything on the existing surface to prevent the bond of the new coating to either the surface or existing marking, the application will fail very quickly. This can be in a time as short as a few days. This is not only a waste of product and time but also of money and investment.
Traditionally, surface preparation can either be a costly or time-consuming task.
The ICAO Aerodrome Design Manual States:
“The surface should be cleaned properly before initial painting and before repainting. The surface to be painted should be dry and free from dirt, grease, oil, laitance, loose rubber deposits, or other foreign material which would reduce the bond between the paint and the pavement.”
We believe that the term cleaning should be more specific and to include…
. . . shall be cleaned by water jet, shot blasting or other mechanical method to remove all loose and poorly bonded paint; and shall be followed by sweeping and blowing or by similar methods as required to remove all dirt, laitance, and loose materials.
Common contaminants found and to be removed include the following:
- Oily substances
- Loose and flaking or poorly bonded paint
- Algae and mildew
- Laitance on new concrete
- Rubber deposits
- Iron staining
2. LOOSE AND FLAKING PAINT
With loose or flaking paint, this again stems back to poor preparation or application. Poorly applied markings perform poorly immediately. If surfaces are damp or humidity levels are too high when applying paint, the risk of flaking is dramatically increased.
As previously discussed, the most important aspect of a surface marking is visibility. Markings should be as visible during darkness as they are during daylight. To produce a vibrant marking, you must consider adopting the following points.
- Are you using a quality high build paint?
- Are you laying the right paint in the right areas?
- Are you using glass beads for your paint applications?
- Do you need to utilise the use of blacking out borders?
To achieve an optimum line or marking you need to make sure that the whole application is of a high standard. All the efforts to increase visibility with black borders, glass beads and best products are futile if the markings are not applied well.
WAYS TO IMPROVE VISIBILITY
As mentioned above, markings should be as visible during darkness as they are in daylight. Markings that cannot be seen [at night] by pilots and others operating on marked surfaces pose a potential risk for those using the area.
REFLECTIVE BEADS
Reflective beads are glass particles that are embedded in to the paint at the time of application/ The beads provide high reflective properties, (similar to CATS Eyes seen on road) to ensure the marking is visible in low-light situations. There are many beads designs available. Some specially formulated for airport applications, to suit the harsh environment and provide enough reflectivity to fully benefit those seated above the ground in aircrafts. If you are interested in our airpt grade glass beads then get in contact with us today.
To achieve an optimum line or marking you need to make sure that the whole application is of a high standard. All the efforts to increase visibility with black borders, glass beads and best products are futile if the markings are not applied well.
The use of Type III reflective beads means that marking can be clearly seen up to 60m above ground and over 30 meters ahead from ground level.
On the other hand, Type I & IV beads can only be seen as far as 6-10m ahead and only from lower levels. See illustration images below:
This is the view from 60m above ground in darkness.
(Arrow heads: Applied with Type III Beads – High reflectivity)
(Arrow Tails: Applied with Type IV – Low reflectivity)
Shows standard (unbeaded line) with visibility of up to only 10m ahead in darkness.
In Summary
For airport markings to be fully effective, they need to offer a high contrast to the surrounding surfaces and be clearly visible and understandable. For markings to be highly visible during daylight, the products applied need to offer a high luminescent value, a bright colour contrast (whiteness) and a crisp line edge to offer clear delineation.
Meon can help you overcome any issue that you may face at your airfield with defective markings. Please get in touch, to discuss any concerns or issues that may have, or book an appointment for us to complete a free audit and report on your surface markings.
If you have any questions about your line markings, please get in touch with us today to discuss your airport marking needs.
BERT SPENCER | 023 9220 0606
