A commercial pilot appoaches a runway with a fully-loaded passenger jet. It is late in the evening in a driving rainstorm with less than desirable crosswinds on the ground. Speaking recently with a commercial pilot about landing in these conditions, he said his only hope was that the people on the ground had done their job as well as he intended to do his. Even on a clear day at high noon, a properly maintained pavement surface is critical to a pilot’s control of the plane once it is on the ground.

Several weeks ago, we received an e-mail from the U.S. Embassy in Brasilia, Brazil. Our contact there had just been in a meeting that included the U.S. Ambassador to Brazil. At the time of the meeting, Brazil was experiencing a period of unusually heavy rainfall. On at least two occasions, commercial aircraft landing at one of their major airports had slid off the runway because of the combination of rain and rubber build-up. A judge had ordered the airport closed until the runway conditions improved. Given the fact that the airport was a domestic hub, air traffic throughout Brazil was seriously interrupted. The ambassador had inquired if anyone in the meeting knew how conditions like this were handled in the U.S. Our contact informed the ambassador that the Brazilian agency with oversight of the country’s airports had sent their senior engineers to the U.S. to review the Stripe Hog® Rubber and Pavement Marking Removal System. The system had been procured and would soon be operational in Brazil. Given the fact that Brazil represents the third-largest business aviation market in the world, this is indeed a significant step forward.

The cleaning of rubber deposits from runways with ultra high pressure water is not a new idea in many parts of the world. In North America and Western Europe, contractors have been successfully doing so for at least 20 years or more. In fact, there are now several airports that have chosen to purchase their own waterblasting equipment for the regular maintenance of their runways, taxiways, aprons and gate areas. In the U.S., an FAA Advisory Circular, AC 150/5320-12C, lists high pressure water as an accepted method of runway cleaning. Today, the driving force behind the advancement of this technology is the demand for better results in less time, for less money.

Runway cleaning is first and foremost a safety issue. It must be done carefully, with proven equipment and properly-trained operators. As in any other industry, not all waterblasting equipment is created equal, and the equipment will only perform as well as the operator enables it to. In the past, there have been cases where waterblasting equipment has damaged runways, and those who promote competitive methods seem married to the idea that it will always be so. An outstanding example of the opposite being true is at a major airport in the Great Lakes region of the U.S. For 15 consecutive years, a leading runway cleaning contractor in the U.S. has cleaned the same runway with ultra high pressure water without causing damage.

The exciting news for airports is the emergence of a new generation of waterblasting systems specifically designed for non-damaging rubber and paint removal with simultaneous vacuum recovery. What is most exciting is that an operation that for many, many years has required three or more trucks — a chemical applicator, one or more steel broom trucks, a water tanker for rinsing, one or more vacuum sweepers and a half dozen or more personnel — now can be accomplished with one truck and a single operator. The advantages to the airport are that the runway closure time is significantly shortened, the equipment logistics are dramatically simplified and the costs are considerably reduced. And perhaps best of all, airports themselves can now purchase a single truck that will remove rubber build-up from runways, painted markings from runways, taxiways and gate areas, and will rejuvenate existing markings that do not need to be replaced but only need be brought back to life. In addition to applications on the airfield side of the airport, pavement markings on landside roads, walkways and in parking areas, as well as many other surface preparation and cleaning tasks can be performed with the same machine throughout the entire airport complex.

Recently, a runway at an international airport in Florida was cleaned by the Stripe Hog®. In the words of the airport airfield maintenance supervisors, the cleaning was quicker, cleaner and with less equipment and staging required than previously used methods. A 280,000-square-foot job was completed at a removal rate of 18,000-square-feet-per-hour. At the conclusion of the job, a sample of the recovered debris was sent to an independent, ISO 9001 certified, materials testing laboratory where the first phase of testing determined that 88 percent of the recovered debris was of an origin consistent with the composition of a rubber tire. While the second phase of testing has not yet been completed at the time of this writing, technicians are of the opinion that the majority of the remaining sample could likewise have as its origin, a rubber tire.

After the cleaning, the Florida Department of Transportation conducted the mandatory friction test. The average friction value was 0.68, with a margin of 0.28 above the desired level of 0.40. The runway cleaning was a success by every account. Ironically, the same equipment was back at the same airport a few days later to remove painted lines in the airport parking garage. While the same equipment was used to perform two very different tasks, do not make the mistake of thinking the equipment configuration was the same for both applications. Proponents of runway cleaning with chemicals, steel brooms and excessive amounts of water for flushing purposes would have you believe that all waterblasting is performed with the same configuration for every application. A successful waterblasting contractor knows that this is simply not the case.

The use of ultra high pressure water for the cleaning of runways is here to stay. Airports around the world are recognizing the simple fact that it is cleaner, quicker, less complicated, more cost-efficient and just as reliable as all other methods. There are established and reputable contractors throughout the U.S. and abroad who are serving both our airports and the waterblasting industry well. The choice for airport managers is clear: Continue to use methods that are labor-intensive, time-consuming and at best, environmentally questionable, or join those who have chosen an innovative approach that meets a wide range of pavement maintenance needs throughout the airport complex – all the while providing pilots and the traveling public cleaner runways and brighter markings.

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