Flight Mechanics, Flight Control and Aeroelasticity

AM-Move - Analysis and evaluation methods for elastic aircraft designs (part of the joint project Con.Move)

In the project "AM-Move" efficient and accurate flight mechanical evaluation methods for novel control surface concepts are developed. On the one hand, these evaluation methods are to investigate control surface concepts taking into account aeroelasticity in cruise flight and, on the other hand, novel high-lift systems during takeoff and landing. AM-Move is a research project in the Con.Move joint project led by Airbus Operations, which is funded by the German Federal Ministry of Economics and Technology as part of the National Aeronautics Research Program (LuFo V2).

Introduction

In today's aircraft preliminary design, flight mechanical properties have so far been determined using semi-empirical manual methods. These methods allow rapid statements to be made about flight characteristics and flight performance. However, the statements are limited due to the assumed simplifications. Variations of control surface layouts in combination with parameter variations in flight control functions cannot be investigated with these methods - but only much later in detailed aircraft design, when high-quality models and the specialized procedures of the technical departments are available.

The same is true for evaluating the flight performance of continuously variable high-lift systems and for studying the flight performance and flight characteristics of high-lift systems during unconventional approach and departure procedures. Manual methods and empirical approximation approaches neither have the necessary accuracy for such problems nor can they analyze dynamically complex and unsteady flight phases, such as gust passes.

If geometry, mass and stiffness data are known, high-quality aerodynamic and structural data can be generated early in the design process using modern numerical methods such as CFD or FEM. These can be used to develop flight simulations. Based on the use of flight simulations, new evaluation methods are set up in AM-Move to be able to examine aircraft preliminary designs more precisely in terms of flight mechanics.

Objectives

The goal of the project is to contribute early in the development of a commercial aircraft to the overall evaluation of the aircraft with integrated control functions (movables) by:

  •     developing efficient and accurate flight mechanical evaluation methods for novel integrated control surface concepts in aircraft preliminary design, taking into account aeroelasticity
  •     developing efficient and accurate flight mechanical methods for the evaluation of high-lift systems - especially for take-off and landing.

Work Program

The department is working in two work packages.

Adaptable High Lift Settings

This work package investigates how adaptive, continuously adjustable trailing edge flaps (SEHK) can be used to optimize the takeoff and landing performance of commercial aircraft. For this purpose

  •     determine the potential of SEHK in performance calculations
  •     an optimal control strategy is designed
  •     implement the control strategy in the form of an automated function in a real-time, high-quality flight simulation of a typical medium-haul aircraft.

This allows conventional and novel takeoff and landing procedures to be tested for operational acceptability in a flight simulator with pilots.

In addition, a parameter study will determine target values for the aerodynamic coefficients (CL, CD, Cm) of a flap system that would ensure an optimal aerodynamic design of the aircraft (wing with flap system and trim position of the horizontal stabilizer).

Evaluation

In this work package, numerical methods for the evaluation of novel integrated footprint concepts, for elastic aircraft, are developed. These methods allow more precise statements on controllability, flight performance and loads at an early stage in the preliminary design process, so that integrated footprint concepts can already be evaluated and compared with high accuracy. The basis for this is the modular tool chain created in the MOVE.ON project, with which flight-mechanical criteria can be checked automatically (see figure).

Detailed preliminary design data of an elastic aircraft with a reference control surface configuration are provided by the German Aerospace Center (DLR). These will be converted into a flight simulation in a procedure to be set up. The existing criteria database from the LuFo4 project FlightSim, as well as the corresponding analysis methods, will be further developed for elastic aircraft. The reference aircraft will then be equipped with an integrated control surface concept developed by DLR and examined using the flight mechanics assessment method in order to evaluate the potential of integrated control concepts.

Project Partners

  • Airbus Operations GmbH
  • Airbus Group Innovations
  • Deutsches Zentrum für Luft- und Raumfahrt e.V.
  • Fachgebiet für Flugmechanik, Flugregelung und Aeroelastizität (FMRA) der Technischen Universität Berlin

Vorhergehende Projekte

  • Auto-SFS – Automatic Slat/Flap Setting (LuFo IV)
  • FlightSim – Flight Simulation of Innovative Movables (LuFo IV)
  • AeroStruct – Entwicklung einer multidisziplinären Simulationsumgebung für die Analyse und optimierung von Flugzeugen
  • ATLAS2Hybrid – Advanced Technologies for Loads, Aerodynamics and Aeroelastics

Funding