The next time you board a plane and sit down, you may be in a very special seat. It won’t look or feel any different than what you are accustomed to, but it is. Hidden behind all the fabrics, foams and synthetic materials is a thermoplastic composite seat frame that can deliver a 30 percent weight savings vs. a conventional aluminum frame.

This unique thermoplastic, modular-composite seat frame is a weight and cost saver that has caught the attention of an airline industry that needs game changing technology and materials to offset high operating costs, stiff competition, tight profit margins, and volatile oil prices.

And translation opportunities could exist for this light-weight advanced, composite design and development success, since there is such a great history of technology sharing between aviation and automobiles. Each industry shares a common goal — design lighter and more fuel-efficient products.

The weight and cost benefits of the thermoplastic modular composite seat frame are derived from a material and production innovation that reduces process cost, increases process volume, and improves both product aesthetics and overall quality.

Conventional airline seats and seat back frames formed from metals, such as aluminum, are relatively simple to manufacture in volume, but are heavier than composites, thereby adding weight and reducing fuel efficiency.

One alternative to metal, thermoset composites, do not meet updated aircraft interior safety standards. In addition, thermoset manufacturing methods add facility and equipment costs to achieve high-production rates. Also, thermoset composites and their manufacturing processes are not very environmentally friendly.

The new thermoplastic modular composite seat frame is different. It relies on a thermoplastic resin that is combined with carbon fiber to make a low-cost Fortron polyphenylene sulfide (PPS)/carbon fiber uni-directional prepreg tape.

The tape is slit in nominal widths and braided to create high-quality perform blanks, which can be readily molded and consolidated into unique final shapes in a matter of minutes.

Developed by Cutting Dynamics Inc. (CDi), along with Ticona Engineering Polymers, TenCate Advanced Composites, and A&P Technology (A&P), this modular composite seat assembly is the winner of the 2011 JEC Composite Innovation Award for Thermoplastics, based on its technical interest, market potential, partnership, financial impact, and originality.

Early on in the development phase of the match-molded seat back and seat frame, the team recognized it had to overcome process development issues, reduce process cost, increase process volume, and improve product aesthetics and general quality.

The team also recognized that, for a composite material to be correctly used, the design and configuration of the composite parts for the seat back assembly have to be combined in such a way as to take advantage of their physical properties.

It soon became clear that PPS was the matrix of choice, because it can be easily manufactured into tape with carbon, glass, and other reinforcements. It offers processing and eco-friendly advantages, and it can use a rapid manufacturing process to produce stronger and lighter seats at relatively low cost.

PPS is a proven material for use in critical aerospace structures and can reduce cost and weight without sacrificing strength and stability. A semi-crystalline polymer, it offers the lowest cost material solution of the thermoplastics available for use by the aerospace industry and provides key features:

• Exceptional high temperature performance to temperatures up to 240º C (464ºF) as demonstrated in under-the-hood applications.
• Outstanding resistance to aircraft and automotive fuels, oils, solvents, and anti-icing agents, and extremely low moisture absorption.
• Excellent hardness, stiffness, and dimensional stability.
• Inherently flame-resistant — meets U.S. Federal Aviation Administration flame smoke and toxicity (FST) requirements and heat generation specifications for aircraft interior applications.

The process advancements behind this modular composite seat assembly that relies on PPS/carbon fiber uni-directional aerospace grade prepreg tape is areal solutions innovation. Ticona as the supplier of the PPS engineered thermoplastic resin; TenCate as the manufacturer of the thermoplastic unidirectional tape; A&P as the preform braider; and CDi as the fabricator worked together to develop a PPS/carbon fiber uni-directional aerospace grade prepreg tape, which is braided into a perform and shaped into a complex tube.

Not only does the new process enable the complex tube to exactly meet the geometry and mechanical requirements of the seat frame, but production is capable of achieving high volumes unique in the aerospace industry. In addition, the process takes less energy to manufacture and the parts are recyclable, making it a real green solution.

So, the next time you’re jetting off to another destination, it’s very likely the seat you’ve chosen looks and feels the same. But it could very well be a special seat that represents a future the aerospace industry is aggressively exploring — one that incorporates more composites in their designs.