No material is left behind in the race to reduce weight in aircraft design, not even sealants.  Simrit, the industrial sealing products division of the Freudenberg and NOK Group companies, stepped up the plate to develop a low-density silicone material that reduces weight by 15 to 20% compared to similar materials. With a specific gravity of less than one, it has the same physical properties of traditional silicone materials, but weighs less. 

It turns out that the nacelle system, the housing that contains aircraft engines, is a critical area for weight savings and fuel economy improvements. Simrit’s silicones, specifically its AMS 3302 and AMS 3303 compliant materials, helped reduce the weight and exhibit properties that could work for several aerospace sealing applications. These low-density silicones operate at temperatures anywhere from -85 to +401°F (-65 to +205°C). They set at a durometer of around 50 to 60+ Shore A. Like most silicones, they resist common aircraft fluids and can also work in fireproof constructions.

The material is produced at Simrit’s Nadcap-approved Tillsonburg, Ontario, Canada plant. The plant is certified to the AS9100 Revision C quality management system including design for the aerospace industry.

More information:  
http://www.simrit.com