Flight Mechanics, Flight Control and Aeroelasticity

GUSTAFO - Gust Load Alleviation by Folding non-linear Wing Tip


GUSTAFO-TUB is the partner project of the TU Berlin in the joint project GUSTAFO (Gust Load Alleviation by Folding non-linear Wing Tip) for the development of a numerical simulation model for the flight-mechanical investigation of novel aircraft configurations with folding outer wing concept. It is funded by the German Federal Ministry for Economic Affairs and Energy (BMWi) as part of the national aeronautics research program (LuFo VI-2). The duration is 36 months (01.06.2022 - 31.05.2025). RWTH Aachen University is the lead partner.

Main Objectives

Two important levers for reducing aircraft energy consumption are structural weight and aerodynamic efficiency. Aerodynamic efficiency depends on the aspect ratio of the airfoil and can be improved by increasing the wingspan. To avoid a limitation of operable airports, a foldable outer wing segment is a good solution. If this is not rigid but connected to the wing by an appropriately designed elastic hinge, a reduction in structural loads can be achieved in the event of turbulence due to the free compensating movement.

The aim of the joint project GUSTAFO is to improve the aerodynamic efficiency of aircraft by increasing aspect ratio using a flexible outer wing segment without increasing structural loads or impairing flight characteristics. For this purpose, a system dynamic overall simulation is to be set up at the TU Berlin, which takes into account the coupling influence of the flexible outer wing segment on the aeroelasticity. By means of this simulation, the aircraft dynamics are to be investigated and an optimal design of the folding wing system is to be carried out. The relationships derived in the project are to form the basis for simplified models that will enable integration of the folding wing technology into the overall platform for the UNICADO aircraft preliminary design.


Project Structure and Tasks of the TU Berlin

The joint project is divided into four main work packages (HAP) which are coordinated by the joint leader (RWTH-Aachen).

HAP1Technology integration/assessment
HAP 2Wing configuration
HAP 3Overall numerical model development
HAP 4Aerodynamic design

The tasks of the TU Berlin are handled at the Department of Flight Mechanics, Flight Control and Aeroelasticity. TU Berlin is involved in HAP 1 and HAP 3.

In HAP 1, the TU Berlin is involved in the definition of the reference aircraft (WP 1.1). The design of the new wing with foldable outer wing segment is to be carried out for this in the further course.

The main work, for which the TU Berlin is primarily responsible, is carried out in HAP 3. Based on the descriptions of the reference aircraft and the new configuration developed by the partners, a numerical model is developed for the overall system dynamics of the aircraft with a highly elastic, widely stretched wing and foldable outer wing segments (WP 3.1). The dynamic behavior is analyzed (WP 3.2), and based on this, an optimal design of the folding wing system is performed, which ensures aeroelastic stability (WP 3.3). As part of an iterative design process, the wing design will be optimized by RWTH. Once a final design has been established, the behavior of the aircraft with the newly designed folding wing can be analyzed flight mechanically, compared with the reference configuration and evaluated (WP3.4). The knowledge gained will form the basis for the integration of the folding wing technology into the aircraft preliminary design tool UNICADO, which RWTH is carrying out as part of HAP1.


  • Rheinisch-Westfälische Technische Hochschule-Aachen (RWTH Aachen)
  • Technische Universität München (TUM)
  • Industriepartner: Liebherr


Organization name Flight Mechanics, Flight Control and Aeroelasticity
Office F 5
Room F 342


Project duration: 06/2022 – 05/2025           

LuFo VI-2