Area de-icing
Special products are available for de-icing surfaces at airports . This movement area deicer for the runways and for other areas at airports, such as B. runways and aprons are solutions or granules based on glycol , urea , acetate or formate .
Importance of runway clearance and de-icing
There must be no objects on the runways that could be sucked in by the engines and damage them.
In addition, the tracks, like roads, must be kept in a condition in winter too, which ensures sufficient friction between the tires of the chassis and the track surface. Deposits on the ground, such as slush, not only lead to a reduction in ground friction, but also increase the rolling resistance of the aircraft wheels. These factors influence the control and braking ability of the taxiing aircraft and the parameters for take-off and landing . Serious accidents have already occurred in this context, for example British European Airways flight 609 . On an airport site, clearing the runways has priority over clearing other areas. In view of the large areas that have to be worked on, considerable amounts of overburden, for example snow, can be produced. Also next to the runways, only a certain amount of snow may be reached in order to avoid accidents that could result from contact with the wings (see Ringelpiez ). Chemicals for deicing the floor surface must be tested for their toxicity , environmental compatibility and possible interactions with the floor covering or the aircraft envelope. Their escape into natural waters in the vicinity of the airport may require additional measures for wastewater treatment.
The icing up of runways can lead to aircraft accidents and, through precautionary shutdown, have significant consequences for the respective airport and international air traffic. The storage and distribution of movement area de-icers poses a logistical challenge.
functionality
De-icing agents are also used in a similar context to de-icing the surfaces of the aircraft themselves. However, the main focus is on the flight characteristics of the machine.
The substances melt ice by lowering the freezing point of their mixture with water. ( Freezing point lowering ) Depending on the concentration, the freezing point can be reduced to as low as −60 ° C. The liquid on the floor will only freeze again when the concentration of the chemical has fallen so far through runoff and new precipitation that the freezing point of the current mixture has risen above the current temperature of the soil.
In order to save de-icing agent, a coating that is supposed to bind the agent as a depot was developed and tested on behalf of the American Federal Aviation Authority (FAA). No benefit was found.
Standards
The Society of Automotive Engineers (SAE) formulates standards for the de-icing of taxiways and runways. Relevant here are AMS 1431 C, AMS 1435 A and B, and AMS 1426 C.
Products and Manufacturers
Examples of products offered are Clearway , a group of biodegradable liquid and solid organic salts based on acetate and formate, Safeway KA based on potassium acetate , GEN3 Runway Deicer made from acetates and polyols . or Cryotech E36 , also potassium acetate.
Web links
- Runway deicing fluid is environmentally friendly from: Tribology and Lubrication Technology, January 1, 2009
- Insights: Winter service at Nuremberg Airport on YouTube
Individual evidence
- ^ A b Heinrich Mensen: Planning, layout and operation of airfields, p. 538 . Springer, Heidelberg 2007, ISBN 978-3-540-68106-9 . online: limited preview in Google Book search.
- ↑ David Blatner: How to get up and down again: everything you always wanted to know about flying, pp. 53–54 . Campus Verlag, 2003, ISBN 978-3-593-37314-0 .
- ↑ Rehabilitation of the southern runway at Cologne / Bonn Airport with Portland slag cement, p. 12. (PDF; 708 kB) Accessed on January 18, 2011 .
- ↑ Süddeutsche Zeitung online on January 4, 2010: Dortmund Airport - De-icing failed? Retrieved January 18, 2011 .
- ↑ Süddeutsche Zeitung online on December 22, 2009: Snow chaos at the airport - Germany's largest airport closed. Retrieved January 18, 2011 .
- ↑ MM Logistik: Liquid transport - snow and ice-free runways at Europe's airports. Retrieved January 18, 2011 .
- ^ Nathan M. Carroll, Barry J. Dempsey: Anti-Icing Pavement Coating Study at Chicago O'Hare International Airport . March 2007 ( faa.gov ).
- ↑ SAE homepage: Search results for "runway" and "deicing". Retrieved January 18, 2011 .
- ↑ Kemira: Clearway de-icers. Retrieved January 18, 2011 .
- ↑ Company Salz Helmreich: Product description. Retrieved January 18, 2011 .
- ↑ Weyer Airport Supply: Product Description. (No longer available online.) Formerly in the original ; Retrieved January 18, 2011 . ( Page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.
- ↑ Cryotech Lab: Product Description. Retrieved January 18, 2011 .
