Servizi Elicotteristici Italiani (SEI) has received EASA certification for its lightweight cabin-noise and vibration-reduction system called Silens. The system was approved on an AgustaWestland AW139 and FAA certification is expected early this year.
Originally developed in Italy in collaboration with AgustaWestland, the system has demonstrated a reduction in cabin noise from 76 dB (SIL4) to 71 dB (SIL4) at a cruise speed of 140 knots. According to SEI, the reduction allows passengers to converse normally without headsets.
The system uses a number of methods–including installation of a self-supported separation barrier between the passenger cabin shell and fuselage skin–to reduce noise. At the core of the system is a high stiffness-to-weight ratio composite shell that ensures full separation between the cabin and fuselage structure through vibration- and noise-insulation attach points.
The thermal/acoustic barrier was developed with the aid of analytical energy and noise-abatement software models, and includes advanced soundproofing materials, alternative geometries and special installation techniques.
According to SEI director of business completions Davide Marucco, the system is compatible with a full range of executive configurations and can be retrofitted on all AW139s, with hinged or sliding doors.
It is also compatible with SEI’s new “Ifeel” in-flight entertainment system, introduced at Heli-Expo 2010. EASA certification was expected in the first quarter of this year on an AW139.