QinetiQ and Ultra Electronics: working towards quieter aircraft cabin interiors

Citation

(2004), "QinetiQ and Ultra Electronics: working towards quieter aircraft cabin interiors", Aircraft Engineering and Aerospace Technology, Vol. 76 No. 1. https://doi.org/10.1108/aeat.2004.12776aaf.004

QinetiQ and Ultra Electronics: working towards quieter aircraft cabin interiors

QinetiQ and Ultra Electronics: working towards quieter aircraft cabin interiors

Keywords: QinetiQ, Aircraft, Design, Electronics

As explained by David Howells, QinetiQ is involved in an ongoing study of new concepts in aircraft cabin design. As a result, QinetiQ and Ultra Electronics are poised to achieve a world first by combining active and passive technology to reduce a broad spectrum of aircraft cabin noise.

“Broadband noise”, which originates from the airflow over the fuselage of the aircraft, can be transmitted through the structure and panels into the aircraft interior. The AIRAT (active isolator research for aircraft trim panels) system involves attaching aircraft trim panels to the airframe using a new hybrid mount that incorporates both active and passive elements. By attacking this transmission path and reducing the panel vibration, the new mounts can achieve substantial reductions in internal cabin noise levels.

Researched and developed by scientists at QinetiQ, this technology is the result of a 7-year study funded by the DTI. Laboratory tests performed on synthetic trim panels indicate an improvement in performance over the existing mounts of at least 10 dB. A ground-based demonstrator will be available later this year and a full flight demonstration is planned for early 2004.

“It's no secret that noise can significantly decrease the overall comfort level for passengers and crewmembers,” says Ron Van Manen Vice-President, Commercial Aircraft Programmes. “Airlines and customers are demanding lower interior noise levels, so aircraft manufacturers and retrofitters are searching for solutions.”

Mr Van Manen added: “Ultra Electronics is widely recognised as a world leader in the active reduction of noise and vibration in aircraft cabins. By partnering with them and building on our experience in vibration isolation, QinetiQ has developed an innovative approach to isolating the vibration of all interior panels, structures and surfaces.”

Rob McDonald Vice-President of Marketing and Support at Ultra Electronics, says that AIRAT is a significant step toward the “Holy Grail” of airline travel: the removal of cabin noise. “Ultra Electronics is already transforming journeys on corporate and regional aircraft for tens of thousands of passengers worldwide.”

“With AIRAT, the promise of completely removing the adverse effects of noise comes even closer,” says McDonald. “We are committed to improving passenger comfort in all aircraft types. We recognise that today's traveller is no longer prepared to endure the extremes of noise and vibration which once characterised the aircraft industry”.

Technology

Passive isolation of the panel provides good performance at higher frequencies, however maintaining that performance at lower frequencies would involve a serious weight or size penalty. By combining passive and active technology, this low frequency problem has now been resolved. Better still, the hybrid approach adopted provides the opportunity to optimise the passive element, with the focus now on its high frequency performance. This has led to an innovative design for that element. Combined with the active system, the new mount has the potential to provide reduced transmission compared with existing mounts over the entire range of audio frequencies.

Industry related experience

Ultra Electronics, the UK-based aerospace and defence electronics group, already offers an innovative range of Active Noise and Vibration Control products based around the UltraQuiet system. The company has pioneered the introduction of practical systems into regular passenger service and now offers fully certified, affordable solutions for a variety of aircraft types. In 2000, the UltraQuiet Cabin, Active Noise and Vibration Control System, was awarded Millennium Product Status by the Design Council.

QinetiQ, Europe's leading science and technology solutions provider, has been developing a number of key innovations to address many of the long-standing discomforts faced by millions of air travellers around the world. Air filtration systems, non-absorbent materials, adaptive lighting systems and advanced communication systems which can provide cabin crew with valuable information concerning passenger needs and special requirements – these are just a handful of the technology solutions QinetiQ is providing to an airlines industry that is demanding differentiation and enhanced passenger services.

Details available from: QinetiQ Group Ltd. Tel: +44 (0) 8700 100 942; Web site: www.qinetiq.com