Maple seeds determine optimal flight route for unmanned helicopter

Esdoorn vluchtHow can an unmanned helicopter land safely even after its engine fails? The answer can be found in flights of maple tree seeds, as researched by NLR’s Skander Taamallah.

The seeds of the maple tree – nicknamed ‘little helicopters’ – are constructed in such a way that as they fall they create lift and hence fall slowly towards the ground. These flight conditions (i.e. auto-rotation) ensure that the wind can spread the seeds far and wide. “When the maple leafs fall, they turn like a helicopter in auto-rotation. Consequently, I used this – Mother Nature’s seed spreading concept – during my PhD research to allow for safe landings of unmanned helicopters,” Skander Taamallah says.

Auto-rotation is the effect that occurs when the engine of a helicopter stops working, whereby the main rotor and tail rotor are still able to rotate freely. If a helicopter has enough height and/or speed, the rotors will keep turning, thus allowing the helicopter to enter a gliding flight and land safely.

Skander Taamallah began by modelling the dynamics of a small-scale helicopter, which he then studied in a simulated helicopter environment. His next step was to calculate the optimal flight path of the unmanned helicopter whose engine had failed. To establish its optimal flight profile, he established the speeds at which the unmanned helicopter would be travelling for all altitudes, from the start of the descent to landing. Skander Taamallah concluded his PhD research by developing a control algorithm, which ensured that the helicopter would remain flying as close as possible to the optimal flight path during the entire descent.

Skander Taamallah however still faces a key challenge: in order to validate his simulations, he intends to use a small-scale, unmanned helicopter to test the automated auto-rotation during a real flight. We eagerly look forward to it!

Skander Taamallah received his PhD from TU Delft on September 18th 2015. You can download his dissertation Phd book.

Michel Peters named Vice-Chairman of IFAR


Global solutions for major aviation questions

Michel Peters, CEO of the Netherlands Aerospace Centre (NLR), was appointed Vice-Chairman of IFAR, the International Forum for Aviation Research. Peters was appointed at IFAR’s 6th annual meeting, held at NASA’s Ames Research Center, in California, USA.

IFAR is comprised of 26 global aviation and aerospace research organisations that collaborate in order to jointly address the challenges facing the global aviation sector, such as technological issues that transcend national borders, including emissions, noise disturbance, safety, security and efficient operations.
In the presence of representatives of 21 aviation research organizations, the global leaders in aviation evaluate the progress of technological collaboration pertaining to aviation’s impact on the environment. Examples of this include research into alternative fuels, the development of a comprehensive approach to ATM research, the supersonic aircraft, and wind tunnel tests.

IFAR’s focus is on global issues, which are further subdivided into working groups. Consequently, NASA, for example, leads the ‘Air Transport Efficiency’ and alternative fuels working group. NLR meanwhile leads the ‘Impact of Weather on ATM’ working group. For the NLR, this means that we collaborate with dozens of other organisations to initially identify existing research activities that are globally relevant for this subject and render it possible to exchange associated information.

In addition to promoting scientific and technical expertise, IFAR promotes exchanges of young researchers. Hence, during IFAR’s recent meeting, a Young Researchers conference was held, during which IFAR participants from various countries exchanged ideas pertaining to the future of aviation. For networking purposes, researchers can benefit from the shared use of (for IFAR members and researchers at universities, related to aviation and aerospace)

The NLR follows DLR, NASA and JAXA in assuming the Vice-Chairmanship. The NLR is regarded and renowned as a leading organization in the field of aviation. Michel Peters will assume the chairmanship of IFAR in two years. Peters: “IFAR is an important global networking platform for both CEOs and scientists. IFAR’s focal point is the future of aviation. As the NLR, we must be a part of this platform. NLR is already participating in various working groups, such as ‘weather’ and’ air traffic management’. We do this on a modest scale, as there is no allocated funding available, but we engage in areas of interest.”

The next IFAR meeting will be held in the autumn of 2016 at the Korea Aerospace Research Institute, in Daejeon, South Korea.

More information:
Join IFAR’s Young Researcher Network Virtual Conferences

New Singaporean air traffic control simulator runs on NLR simulation software

narsim_275Nanyang Technological University (NTU) in Singapore recently launched one of the world’s largest and most advanced air traffic control simulators. The new tower and radar simulators run on simulation software designed by the NLR – Netherlands Aerospace Centre. The software is from NARSIM*, NLR’s air traffic control simulator.

Singapore is a small country but of strategic importance for the busy air traffic flows to and from its neighbouring countries, including Malaysia. Singapore’s air traffic control covers the South China Sea, where there is presently little radar coverage. With the recently opened facility, NTU researchers aim to accelerate and support ATM innovations, which will allow them to play a leading role in researching the design of the region’s air space.


In using the NLR’s simulation software, NTU now has a highly flexible research facility at its disposal. Researchers can adapt the entire facility, which could include expanding existing and new tools, altering radar screens or adapting procedure and routes.
Erik-Jan Hartlieb of the NLR: “It is remarkable that NTU can now set up the entire facility itself. They have full access to the source code, and, consequently, NTU is not dependent on suppliers to adapt certain tools or completely develop new ones.”
NTU has set up the facility in collaboration with the Civil Aviation Authority of Singapore (CAAS) and DLR, the German Aerospace Center, who established the design and requirements for the simulators. Reasearch topics slated to be part of the future program include flow management, route optimisation, UAS integration, human factor research, taxi guidance and airborne-assured separation.

The NLR is pleased that NTU has chosen NARSIM for its air traffic control simulator. NLR representatives have meanwhile led courses and trainings at NTU, so that NTU can get to work using NARSIM. NTU can also turn to NLR for any future support (updates and questions). DLR in collaboration with NLR, set up a demonstration environment for the Changi tower and radar air traffic control.

User community

NTU is also now a member of the NARSIM user community, joining NLR, DLR, and LFV, the Swedish air traffic control organisation. The aim of this community is to jointly expand and improve the NARSIM simulation software. Participants learn from each other’s NARSIM simulations, ATC tools, concepts, airspace design and ATC procedures, and they can also use each other’s NARSIM developments. Partly owing to the compiled knowledge of the members, NARSIM will continuously evolve to higher levels.

*About NARSIM:

NARSIM is the NLR’s realistic and real-time simulator that simulates the air traffic control environment. It consists of NARSIM Radar (air traffic centre simulator) and NARSIM Tower (tower control simulator). Using NARSIM, the NLR develops, tests and validates new operational ATC concepts, tools, procedures and addresses the human factor in air traffic control. The NARSIM software is fully scalable and can be used from a single laptop to a large-scale integrated radar and tower environment with multiple workstations and controllers pilots and outside view. More info: