For the measurement campaign, a series of microphones were positioned at various places inside the engine and around the exhaust area and recording their signals simultaneously. These signals formed the basis for the acoustic field analysis.
Credit: DLR (CC-BY 3.0).
In a helicopter engine, temperatures of up to 1200 degrees Celsius and pressures of up to 12 bar prevail. Microphones that were specially developed by DLR were used.
Helicopters like the FHS at DLR owe their unique manoeuvrability to the rotor. However, aerodynamic phenomena prevent their performance from being fully exploited.
Model of a helicopter rotor blade in the transonic wind tunnel. Air is blown through openings near the leading edge in order to improve the aerodynamics.
The laser sensor of ALLFlight (Assisted Low Level Flight and Landing on Unprepared Landing Sites) is integrated into the small box below the helicopter. In the framework of DLR's ALLFlight research project, scientists are developing a system to generate a digital map for the cockpit and assist the pilots in difficult situations - up to a fully automated landing.
The rotor test facility at the Institute of Flight Systems.
DLR's FHS research helicopter during a test flight in wind conditions. Helicopters can rescue people in danger as well as transport particularly bulky and heavy loads. For this reason, it is important that the helicopter and its external load remain stable and under control during flight. DLR has developed a pilot assistance system (project HALAS - helicopter external load assist system), to stabilise and precisely position the external loads on the helicopter automatically, without intervention of the pilot. This is the purpose of DLR's research helicopter FHS (Flying Helicopter Simulator), a converted Eurocopter EC 135, equipped with the necessary hardware.
Ian Phillis from the Empire Test Pilot School (left) and Waldemar Krebs from DLR, ready for flight.
Credit: DLR/Marek Kruszewski.
The ACT/FHS 'Flying Helicopter Simulator' of the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) at a flight in 2009.
The five-seater Bölkow BO 105 helicopter has been considerably modified by the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR). The Eurocopter's service portfolio is very wide-ranging and can be used for diverse research missions.
During a test flight, ACT/FHS uses the ALLFlight (Assisted Low Level Flight and Landing on Unprepared Landing Sites)system for landing.
DLR's ALLFlight (Assisted Low Level Flight and Landing on Unprepared Landing Sites) research project involves the development of a system that generates a digital map for the cockpit, and helps the pilots in difficult situations - up to a fully automated landing. A total of four sensors are used in the creation of three-dimensional digital environment maps: TV camera, infrared camera, laser and radar. Once the data is combined, the pilot will only see a picture of the environment. On the top right is the environmental image obtained with the TV camera. The 3D image is visible on the left.
Part of the team involved in DLR's research project ALLFlight (Assisted Low Level Flight and Landing on Unprepared Landing Sites), which will develop a system to create a digital environment map for the cockpit and help the pilots in difficult situations - up to a fully automatic landing. The last succesful test flight of 2011 was conducted with the DLR research helicopter ACT/FHS (Active Control Technology/Flying Helicopter Simulator) on Monday, 5 December 2011.
While looking for a way to prevent dynamic stalling in helicopters, DLR researchers in Göttingen struck gold with humpback whales. These marine mammals are renowned for their great speed and acrobatic skills. This is due to their unusually large pectoral fins, which have characteristic bumps along the front edge. DLR researchers translated the idea of using bumps for delaying the onset of stalling to helicopter rotors, and tested it out using the Bo 105 research helicopter.
Credit: DLR/istockphoto.com/Josh Friedmann. Photomontage: DLR.
A computer simulation shows turbulence around a rotor blade when the airflow separates from the aerofoil. This phenomenon, referred to as a 'dynamic stall', occurs on a backward-moving main rotor blade during fast forward flight or manoeuvring.
A test candidate from the Germany Armed Forces during the first trial of the new helmet mounted display in the generic cockpit simulator at the DLR Institute of Flight Guidance.
Initial ground tests with the new helmet mounted display in a research helicopter at DLR Braunschweig.