Eurocopter’s Blue Pulse™ active noise reduction system has demonstrated its ability to significantly reduce a helicopter’s acoustic profile and dramatically decrease in-flight vibration. Flight tests with this piezo-active main rotor blade control system have demonstrated noise reductions of up to 5 dB, while also bringing vibrations to “near jet-smooth� levels, according to Yves Favennec, Eurocopter’s Research and Innovation Vice President. The primary objective of Blue Pulse™ is to treat the interference of rotor blade tip vortices from one rotor blade with the following blades. Its control system uses three flap modules on the trailing edge of each rotor blade, which are driven 15 to 40 times per second by piezoelectric actuators located inside the blades themselves. “Tests performed since 2005 have provided very good results, both in terms of noise reduction and in the decrease of vibration – which creates a smoother ride for passengers and should extend the lifetime of sensitive onboard components such as electronics,� Favennec said. “We are now are fully exploring all of the cost and maintainability aspects for this active system.� Blue Pulse™ is part of Eurocopter’s bluecopter® technology program to develop and validate advanced technologies offering environmental benefits for the company’s rotary-wing aircraft. It is complementary to the Blue Edge™ double-swept main rotor blade concept – also on display at Heli-Expo 2010 – which is a passive “plug and play� solution that has shown a 3-4 dB noise reduction during a helicopter’s descent.