Our Design – How does it work?
In case of an overrun, the landing gear of the airplane will immediately engage into, the greenEMAS bed by crushing the beds´ main components. The crushing is an irreversible process in which the amount of energy that is dissipated is proportional to the arresting performance of the system. The main material responsible for the energy dissipation is the silica foam aggregate (foam glass). Crushing of the foam glass, combined with crushing and displacement of the top slab produces drag loads on the landing gears, which in return reduces the speed of the aircraft, bringing it to a safe stop.
“Safety and long-term commitment will always be our priority no.1.”
Construction – How is it constructed?
greenEMAS is a monolithic bed of silica foam aggregate (foam glass), capped with a cover slab, made of Controlled Low-Strength Material (CLSM), and a multilayer top coating.
PAVEMENT – Our greenEMAS requires a paved base capable of supporting the specific fleet mix, both directly under the bed itself and in any areas between the threshold and the start of the bed, normally referred to as the setback. All materials are standard, locally available construction materials, except for the foam glass and the cover slab.
FOAM GLASS – The silica foam is always sourced from Runway Safe certified production plants, which has passed careful testing and implementation of Runway Safes quality routines in order to ensure the required arresting characteristics.
The CLSM (cover slab) is anchored to the underlying pavement using pavement anchors, low profile galvanized struts and geogrid plastic membrane (embedded in the cover slab) to ensure high jet blast resistance. It is also equipped with drainpipes for inspection and moisture removal. The cover slab includes contraction and expansion joints to limit cracking. The unique cover slab is always blended close to the airport construction site by local batching plants under the supervision and control of Runway Safe.
TOPCOAT –The multi-layer top coating consists of several layers for protection of the CLSM, extending its life and reducing the scope of any maintenance-need for the greenEMAS system. The primary layer is a sealer treatment which makes the surface hydrophobic, limiting the moisture penetration and optimizing the freeze and thaw characteristics of the bed. Additionally, it is coated with an acrylic paint for wear and tear protection of the surface, which is available in various pigments, so that the chevrons and adjacent areas are made of the same material but with different markings. Due to the cementitious nature of the CLSM, a specific pattern of contraction joints is necessary to reduce cracks that will appear over time.
Tailor made design for your airport
Runway Safe adapts each and every greenEMAS design according to the most optimized size, which can arrest the entire fleet mix at exit speeds between 40 and 70 knots. The size and arresting performance of the greenEMAS is highly dependent on the national regulations as well as specific to individual requirements of airports such as available space, topography, fleet mix etc. The design goal is made with the suitable conditions in mind in order to optimize the arresting performance. An optimized greenEMAS arrestor bed always includes the foremost fitting solution based on all types of airport specific fleet-mixes – from smaller aircrafts to larger airplanes such as Boeing 777 for example.
The key features of the greenEMAS system are:
- Safe and controlled deceleration of aircrafts
- Durable – The greenEMAS is an encapsulated construction. The main component (silica foam) is extremely durable, made of energy absorbing inert material, which is unsusceptible to the elements such as rain, snow and ice.
- Versatile – each EMAS is unique in design and adapted to meet individual conditions of each runway. The dimensions and the jetblast resistance is customized to the specifics of each case.
- Fast installation – built on site with standard building materials, mainly sourced locally. The main component of the greenEMAS system is the foam glass, which is stored at the production plant for rapid delivery.
- Fast repairs – short lead times for repair materials in case of an overrun. The foam glass, which is loose fill material can be stored locally, close to the runway. This enables rapid repairs of the EMAS in case of an overrun.
- Sustainable – our foam glass, made from recycled glass materials is produced using emission free energy, from local Hydro Power. Additional sustainability thanks to less transports and travelling due to locally available building materials.
- Cost efficient – lesser logistics necessary due to locally sourced and stored materials, pour-in-place construction and workforce from our local construction partners.
- Life cycle concept – a long term inspection, maintenance and repair package, including a standard two-year warranty can be offered.