History – Road Map of Events: 1999-2003


Within the program to expand the FBW-flight regime of the In-Flight Simulator ATTAS for research application to touch down and landing first FBW- landing took place on April, 30 at Berlin Schoenefeld airport. Several technical modifications have been developed to allow safe operation also in failure cases near the ground.


A flight test campaign was carried out with ATTAS under contract with the French Test Pilot School (EPNER) at Istres in May 1999. Various aircraft/flight control characteristics associated with large transport aircraft were demonstrated including engine failure modes and virtual ILS-approaches. A further flight test engineer training was carried out at Braunschweig in September 2000 for the Empire Test Pilot Scholl (ETPS) The training syllabus included the flight demonstration of control augmentation systems which had to be designed by the students. Recently implemented user software based on MATLAB/SIMULINK allowed autocoding of the SIMULINK designed control laws by using real Time Workshop (RTW) to real time programs running on the ATTAS target computers.


The name of the
DLR - Institute of Flight Mechanics
has been changed on 17. December 1999.
The new name of the institute is
DLR - Institute of Flight Systems
or, in German
DLR - Institut für Flugsystemtechnik.


The active sidestick development MAGSI was completed end of 2000. The system with an unique elecromagnetic actuation system is scheduled to be flight tested on ATTAS in the EPIAS program (Enhanced pilot information by using active sidestick) to investigate the influences of tactile information in order to improve situational awareness of the pilot. In total seven units were built.

A demonstration setup of a twin MAGSI inceptor arrangement

The ground based system simulator for ATTAS got a new improved vision system. The system has two channels with video projection of 120 degrees in azimuth and 30 degrees in elevation. Further terrain data base was improved to provide detailed Frankfurt and Braunschweig airport sceneries for landing tests. The ATTAS system simulator has to be used to verify user software, prove flight test procedures and to train flight test crews before first flight.


The ground-based ACT/FHS helicopter system simulator as an equivalent to the ATTAS system simulator was completed for testing the experimental fly-by-light equipment and functions before being installed in the Flying Helicopter Simulator (FHS) EC 135 airframe.

System Simulator for the EC 135 Flying Helicopter Simulator FHS

On the occasion of the 20th anniversary of the In-flight Simulator and Technology Demonstrator Aircraft ATTAS a scientific workshop was held at the DLR Research Center Braunschweig and hosted by the Institute on October 16-17. 60 international flight test experts gathered to review the unique capabilities and most important flight test campaigns carried out with ATTAS for the last 15 years.


On 16 August 2001 during a farewell celebration Prof. Dr.-Ing. SM., Peter Hamel was honored for his successful leadership of the Institute of Flight Systems during more than 30 years. Prof. Hamel retired on 1 August. The new director is Prof. Dr.-Ing. Stefan Levedag.

The former and the new Director of the Institute of Flight Systems, Prof. Peter Hamel (left) and Prof. Stefan Levedag, having a chat at the ATTAS 20 Year Anniversary Workshop.

Another 20th Anniversary was celebrated during the bilateral cooperation in the field of Aeronautical Sciences between DLR and NAL, Bangalore, India, at the Embassy of India in Berlin on 25-26 September 2001. The Institute of Flight Systems was one of the leading DLR Institutes in this cooperation which included a multitude of exchanges of scientists and bilateral scientific workshops at NAL and DLR.

His Excellency Mr. Ronen Sen, Indian Ambassador in Germany (right), receiving a detailed brochure from DLR Senior Scientist R. Jategaonkar highlighting the outstanding scientific results of joint work carried out by DLR-NAL (2001).
2001 Higher-Harmonic Control Aeroacoustic Rotor Tests (HART II) as follow-on of the HART I test campaign in 1994. First time to use stereo 3-component particle image velocimetry (3C-PIV) to map the complete rotor vortex system. First time to use stereo pattern recognition (SPR) to measure blade deformations optically. Blade pressure and acoustic radiation measurements complete the database (1 TeraByte raw data) for aero-acoustic prediction codes (cooperation with US Army, NASA, DLR Institutes of Design Aerodynamics, Aeroelasticity, and Fluid Mechanics, and ONERA).
Blade-Vortex interaction visualization during German-US-French HART II wind tunnel tests in DNW-LLF (2001)

DLR performed an in-flight simulation campaign for the Fairchild/Dornier 728 aircraft project under contract to the manufacturer. The host aircraft was ATTAS, whose inceptor's force feel characteristics were matched to the 728 characteristics. The 728 model provided by Fairchild/Dornier was a complete, nonlinear simulator model, including wind tunnel aerodynamics (more than 100 tables, up to 5-dimensional), actuator dynamics including rate and deflection limits, engine dynamics, and the flight control system. In order to achieve the necessary quality of the in-flight simulation for this complex model, a completely new nonlinear model following controller was developed. It is based on an explicit model following control scheme and contains a numerically inverted nonlinear simulation model of the host aircraft in the feed-forward path. Excellent flight results have been achieved, even for maneuvers like flap changes engine failures, and offset landings until main gear touch down.


The new Flying Helicopter Simulator EC 135 successfully completed its first flight with the fly-by-light control system engaged on January 28, 2002. After a dedicated flight test evaluation and acceptance phase the new research helicopter became operational at DLR research airport Braunschweig on November 7, 2002 as the successor of the famous BO 105 ATTHeS. First user programs will concentrate on control law development for the in-flight-simulation capability, international handling qualities investigations, European test pilot training and industrial project support.

The EC 135 Flying Helicopter Simulator (FHS) during the final flight certification and acceptance ceremony (2002)

ASTRA-PHOENIX model of re-entry vehicle for space exploration: helicopter towed flight, design and analysis of air data system, contributions to a “hard-ware-in-the- loop” simulator to test all systems under real conditions on ground. Analysis of flight test data and system identification of the vehicle flight mechanics are further project contributions of the institute.

PHOENIX DNW-LLF wind tunnel tests (2003)

The development of a technology demonstrator for autonomous VTOL flight has been started. Using a small helicopter platform, the Autonomous Rotorcraft Testbed for Intelligent Systems (ARTIS) is designed to be an inexpensive multi-purpose research platform for machine vision, decision systems, collision avoidance functions, multiple vehicle co-operation and advanced flight control research. After a short development time for the basic avionics package, first flight tests with a fully instrumented vehicle were carried out in May.

ARTIS - Autonomous Rotorcraft Testbed for Intelligent Systems

First successful operational demonstration flights with the airborne simulator VFW 614 ATTAS flying in a simulated high altitude long endurance (HALE) reconnaissance mission as an unmanned air vehicle (UAV) have been accomplished until May 2003. Main research objective of the collaborative project between the DLR Institutes of Flight Systems and Flight Guidance and EADS, ESG, WTD 61 and Deutsche Flugsicherung is the demonstration of available and reliable UAV technologies in flights under civil controlled airspace rules. Flight data gathering and increasing operational experience in handling failure modes of systems and data links will contribute to the establishment of certification criteria required for such type of UAV missions. The project will be concluded with a fully autonomous flight until touch-down.

ATTAS Demonstration of unmanned air vehicles (UAV) operating in controlled airspace

In the US-German VECTOR program (Vectoring, Extremely short take-off and landing, Control, Tailless Operation Research), the X-31A has advanced in new regions of the flight envelope. During ESTOL (Extremely Short Take-Off and Landing) maneuvering, the VECTOR aircraft successfully approached at extremely high angles of attack and automatically de-rotated to more conventional (lower) pitch attitudes for landings without tail strikes just seconds prior to main wheels touchdown. For control law design, a detailed and sound knowledge of the aerodynamic characteristics in ground effect was imperative. The addition of a nose cone with strakes to accommodate a new Flush Air Data System from EADS and relocating the nose boom aggravated the task to accurately predict and identify the stability and control characteristics of the X-31A. The Institute's system identification tools and parameter estimation results played a major role in providing flight control design inputs and to validate the aerodynamic model in ground effect.

X-31A VECTOR landing in tail-below-wheels pitch attitude prior to de-rotation

URL for this article