S.E.I. (Servizi Elicotteristici Italiani) S.p.A., a Mecaer Aviation Group company, has received certification for its lightweight cabin noise and vibration reduction system called SILENS. The system has been EASA certified on an AgustaWestland AW139 helicopter, with FAA certification expected early in 2010.

Originally developed in Italy in collaboration with AgustaWestland, the system has been proven to dramatically improve passenger comfort, reducing noise levels and distribution in all flight conditions. Flight tests have demonstrated a significant noise abatement in all conditions, with a remarkable reduction from 76 to 71 dB SIL4 at a cruise speed of 140 knots.

The system minimizes cabin noise and vibration levels using a self-supported separation barrier between the passenger cabin and the fuselage, allowing normal conversations between passengers without using headsets.

The SILENS system core is a high stiffness-to-weight ratio shell which guarantees full separation between the passenger cabin and fuselage structure. The shell is manufactured with extensive use of advanced composite materials and is mounted to the surrounding structure in just few discrete points by means of vibration and noise insulators.

The shell is complemented by a special soundproofing developed with analyticalm energy and noise abatement software models which have been validated with extensive test campaigns, using different state-of-the-art soundproofing materials, alternative geometries and special installation techniques.

S.E.I. S.p.A. director of its completions business unit, Davide Marucco, said, “The great thing about this system is that it maximizes cabin volume available for the passengers, it’s easy to remove to get access to the main aircraft systems for maintenance, and doesn’t increase the weight of the aircraft.

“Furthermore, our revolutionary system is compatible with a full range of corporate and VIP cabin layouts and can be retrofitted on all AW 139s, both with the hinged or sliding doors. In designing the SILENS in collaboration with AgustaWestland, our target was to guarantee the highest performance in terms of passenger comfort while having minimum impact on cabin volume and aircraft weight. All objectives have been achieved and customers have confirmed their satisfaction with the results,” he added.