View Christoph Kessler of the German Space Agency working on a helicopter's rotor blades to reduce the noise
Efforts to reduce the noise generated by a helicopter's rotor blades.
Contunico © ZDF Studios GmbH, Mainz
-
© 2025 Thomson ReutersRobots competed in tennis, track-and-field, boxing, martial arts, and other sports at the World Humanoid Robot Games in Beijing.
-
Contunico © ZDF Studios GmbH, MainzA Boeing 747 undergoing a D-check, an extensive maintenance inspection in which much of the aircraft is disassembled and examined.
-
Encyclopædia Britannica, Inc.It was a world before streaming services.Media Editor: Lauren Sims
-
© Open University (A Britannica Publishing Partner)Learn how a helicopter rotor generates lift.
-
Contunico © ZDF Studios GmbH, MainzAn overview of helicopter air taxis in Istanbul.
-
NASA/Dryden Research Aircraft Movie CollectionThe Lockheed C-5A Galaxy undergoing a wing vortice test at NASA's Langley Research Center in Hampton, Virginia, c. 1970s.
-
NASAThis video shows a takeoff and landing of a crewed U.S. space shuttle. The shuttle's main components are a winged orbiter, a large external tank that carries the liquid fuel and oxidizer for the orbiter's three main engines, and two solid-fuel rocket boosters mounted on the sides of the external tank. The shuttle orbiter is a reusable spacecraft that reenters the atmosphere, makes an unpowered descent, and lands on a runway much like an airplane.
Transcript
NARRATOR: The thundering echo of rotor blades fills the valley long before the propellers can be spotted. Helicopters. They can be heard from afar, but there are plans to change that. High-tech innovations of the future aim to silence the rotor blades. The German Space Agency, DLR for short, in Braunschweig. Christoph Kessler is the director of the helicopter research unit here at the Agency's Institute of Flight Systems. This is where the latest helicopter technology is developed. Noise reduction is an important research area.
This is the prototype for a new kind of rotor blade. It is special because the surface contains integrated piezoelectric ceramic fibers, set apart by their colors. These fibers minimize the vibration of the rotor blades, leading to a significant noise reduction in comparison to conventional rotor blades.
CHRISTOPH KESSLER: "Okay, the static load tests have been run, and there are no problems with the resilience?"
WORKER: "No, there are no problems there."
NARRATOR: These fibers expand under the force of an electric field. They cause a visible rotation of the rotor blades. This warping reduces the vibration of the propeller. The reduced-noise rotor blade is still being tested. It could be ready for mass production and commercial sale in 10 years, at the earliest. Until then, the intrepid flyers will continue to be easier to hear than they are to spot.
This is the prototype for a new kind of rotor blade. It is special because the surface contains integrated piezoelectric ceramic fibers, set apart by their colors. These fibers minimize the vibration of the rotor blades, leading to a significant noise reduction in comparison to conventional rotor blades.
CHRISTOPH KESSLER: "Okay, the static load tests have been run, and there are no problems with the resilience?"
WORKER: "No, there are no problems there."
NARRATOR: These fibers expand under the force of an electric field. They cause a visible rotation of the rotor blades. This warping reduces the vibration of the propeller. The reduced-noise rotor blade is still being tested. It could be ready for mass production and commercial sale in 10 years, at the earliest. Until then, the intrepid flyers will continue to be easier to hear than they are to spot.
Last Modification: