Ground chassis
A ground landing gear (also " landing gear without landing gear ") is a landing gear connected to the ground , on which an airplane can take off and land without its own landing gear. The technical feasibility of floor chassis is currently being investigated by two research groups. In 2013 IATA included the technology in its “Technology Roadmap”, and Airbus is pursuing it as part of its “Future by Airbus” strategy.
Advantages and functionality
The landing gear and associated structures / systems make up 6 to 15 percent of the weight of an aircraft. However, it is only required on the ground for take-off and landing as well as for taxiing and parking the aircraft. During the cruise it is carried as unused mass. An aircraft without landing gear could therefore use 8 to 20 percent less kerosene for flight. Landing gears are also one of the most expensive aircraft systems and are complex to operate and maintain. After all, there is less noise when the air resistance of the landing gear is eliminated and the engines can remain switched off while taxiing.
With a ground landing gear, an aircraft can take off and land without having to carry its own landing gear. Instead, the runway will be equipped with a ground landing gear and the aircraft will be equipped with appropriate interfaces.
Every airport served must have at least one ground landing gear. In addition, alternate airports must be available in the event that an airport cannot be reached due to bad weather or a system failure. In the case of emergency landings outside of runways, unsuitable floor coverings or unpaved ground cannot absorb the high surface load of the wheels. For this reason, the landing gear of heavy long-haul aircraft is often not extended anyway during emergency landings on unsuitable ground, since otherwise it would first sink in and then collapse or break off.
Related concepts
The forerunner of the ground landing gear is the drop landing gear , in which the aircraft takes off on a “take-off sled”, then drops it and finally lands on skids. The Messerschmitt Me 163 "Komet" and the Arado Ar 234 "Blitz" in version A-0 were used in early models . The Schleicher Ka 1 glider, built in the 1950s , also had a drop landing gear. A Sea Vampire Mk.21 landed with its landing gear retracted on a rubber-lined deck of an aircraft carrier.
The idea of the ground landing gear is ultimately related to that of the aircraft catapult , especially with the Electromagnetic Aircraft Launch System that is currently being developed .
GroLaS
"GroLaS" (Ground-based Landing Gear System) is a ground landing gear system developed since 2008 by a Hamburg company in cooperation with the Technical University of Hamburg-Harburg and the German Aerospace Center . The construction of a prototype is currently being planned; the system should be ready for use in 2035. The GroLaS project study initially focuses on long-haul cargo aircraft. When the system is introduced, the world's most important cargo airports and corresponding alternative airports are to be equipped first. The cost of equipping an airport is given as 500 million euros. GroLaS is patented in Europe, the USA and China. A 1:87 scale model manufactured in 2013 was exhibited at the International Aerospace Exhibition Berlin 2014.
It consists of a slide that is accelerated and decelerated by means of electromagnetic drives on both sides of the runway. So the conventional runway can be preserved. When landing, the sled accelerates to the landing speed of the aircraft before touching down and automatically adjusts its position to the aircraft. Supports located in the slide latch into corresponding interfaces in the aircraft. Take-off and landing are also less prone to cross winds thanks to a yaw angle adjustment. The braking energy is converted into electrical current, which is used to support the engines when they are started. The braking distance is shortened, no reverse thrust is required. The slide can be released for rolling.
GABRIEL
"GABRIEL" ("Integrated Ground and on-Board System for Support of the Aircraft Safe Take-off and Landing") is a research project for the development of a ground landing gear system that has been run by a consortium of several European universities since 2011.
The proposed ground landing gear moves on its own electromagnetic path and not on a conventional runway. The supports for docking with the slide are still in the aircraft here. The slide is also released here for rolling and has its own electric drive.
Web links
Individual evidence
- ↑ Stephan Maaß: "In the future, planes should land without wheels" , Welt am Sonntag, November 1, 2009.
- ↑ IATA (Ed.): "IATA Technology Roadmap" , 4th edition, June 2013, p. 25.
- ↑ "Future by Airbus'" ( Memento of the original from August 21, 2017 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , airbus.com.
- ↑ Jan Binnebesel: "Flying without landing gear?" , Mbptech.de.
- ↑ KH Lütjens u. a .: "Airport 2030 - Solutions for the efficient air transport of the future" , German Aerospace Congress 2012, p. 7.
- ↑ a b K. H. Lütjens u. a .: "Airport 2030 - Solutions for the efficient air transport of the future" , German Aerospace Congress 2012, p. 8.
- ↑ Jan Binnebesel: "Flying without landing gear?" , Mbptech.de.
- ↑ Aircraft Accident Investigation Center at the Luftfahrt-Bundesamt (Ed.): "Emergency landing - with landing gear extended?", Aircraft Accident Information V 34 , November 1984.
- ↑ Angelika Hillmer: "Airplanes take off and land without landing gear" , Hamburger Abendblatt, December 3, 2013.
- ↑ Hamburg Aviation: "Future by Airbus" uses ground landing gear concept from Hamburg ( memento of the original from October 20, 2014 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. , October 1, 2012.
- ↑ KH Lütjens u. a .: "Airport 2030 - Solutions for the efficient air transport of the future" , German Aerospace Congress 2012, p. 9.
- ^ "Hamburg at the ILA aviation trade fair" , Hamburger Abendblatt, May 21, 2014.
- ↑ Daniel Rohacs et al. a .: "Preliminary evaluation of the environmental impact related to aircraft take-off and landings supported with ground based (MAGLEV) power" ( 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. , Journal of Aerospace Operations 2 (2013), p. 161.
