Resin cuts aircraft weight and cost

A Sabic Innovative Plastics product story

Edited by the Engineeringtalk editorial team Apr 27, 2007

GE's light-coloured Lexan FST resin can easily be prepared in bright white or any other colour prior to moulding, eliminating the time and cost of painting.

GE Plastics has released Lexan FST9705 polycarbonate (PC) copolymer, a totally new resin platform to help OEMs and aircraft interior suppliers achieve weight-out and cost-out goals without sacrificing processability.

Complementing GE Plastics' high-performance Ultem PEI flame-retardant resins, this new material gives designers a fresh solution to today's stringent performance, regulatory, and aesthetic requirements.

Lexan FST9705 resin is an excellent candidate for such applications as personal service units, window reveals and bezels, and provides a combination of advantages: full flame/smoke/toxicity compliance including OSU 55/55 heat-release performance; moulded-in colour including bright whites; and the ability to produce ductile, thin-wall parts that can contribute to fuel conservation through lighter weight.

Thanks to its inherently light base colour, Lexan FST resin enables bright whites with an L value (measure of the lightness of the colour) up to 94 in CIE Lab colour space.

Moulded-in colour helps reduce the approximately 5kg of paint used in cabins today.

An additional benefit is the durability of the resin surface in high-wear applications, compared to painted plastic.

"The aircraft industry has long been looking for a flame/smoke/toxicity (FST)-compliant material with improved colourability", said Doug Hamilton, Product Manager for Lexan Resin at GE Plastics.

"Now, with Lexan FST9705 resin, GE has delivered".

"This new platform has been engineered to help solve key performance challenges facing interior component designers, particularly weight reduction and paint elimination for parts requiring bright white or integral colours that can withstand UV exposure".

"The ductility of this material also helps achieve lower part cost by enabling thin-wall design".

"In fact, it has the highest ductility of any OSU-compliant material in the GE portfolio".

"Now, instead of limitations from existing resins, customers will see limitless possibilities".

According to the International Air Transport Association, for every kilogram of weight that is removed from a single-aisle plane, approximately US $372 a year is saved in fuel costs.

The average life expectancy for this type of aircraft is approximately 20 years.

In 2005, 10,580 single-aisle airplanes were required worldwide to service the airline industry, and this number is expected to reach 21,470 by 2025.

Likewise, the combined number of regional jets, and single-aisle, twin-aisle, and large airplanes is expected to double by the year 2025.

Previously, designers had to compromise between resin processability and compliance with the Ohio State University standard for heat release.

Lexan FST9705 resin's processability is similar to that of polycarbonate-type products.

Its lower processing temperatures allow customers to avoid oil-heated tooling.

Lexan FST9705 resin also gives designers and OEMs design room to accommodate future heat release requirements, as it provides OSU 55/55 performance.

Aircraft interior suppliers have been challenged in the past to produce parts with reflective surfaces to optimise LED lighting in aircraft interiors.

To counteract the yellowing common to many resins, these parts have required secondary painting operations to achieve a bright white colour.

GE's light-coloured Lexan FST resin can easily be prepared in bright white or any other colour prior to moulding, eliminating the time and cost of painting.

Many interior parts are exposed to impact loads - from baggage being jammed into an overhead bin, knee and foot impact on sidewalls and tray tables, and service carts hitting seating.

The higher ductility of Lexan FST resin is an attractive solution for parts requiring high abuse tolerance.

It is also important for enabling thin-wall applications that reduce part weight and contribute to fuel savings.

GE's Lexan FST resin can be injection-moulded or used in profile extrusions.

Potential applications for the new material include: stow bin threshold trim; personal service units; window reveals and bezels; decompression and speaker grilles; and magazine racks.

This new copolymer platform holds promise for other materials such as high-clarity, transparent resin and sheet products that will satisfy new industry trends such as larger windows, transparent partitions and stairways, and LED lighting panels.