Alcoa says the new technologies, which "combine new alloys and advanced structural technologies," use Alcoa sheet, plate, forgings and hard alloy extrusion products across aircraft structures, including  wings and fuselage elements.

Alcoa claims that these technologies:

  • lower the weight of the aircraft by up to 10% compared with composites - intensive planes;
  • lower the cost to manufacture, operate and repair aircraft by up to 30% compared with composites - intensive planes, and at significantly lower production risk;
  • allow for a 12% increase in fuel efficiency, on top of the 15% from new engines; and
  • deliver passenger comfort features equivalent to composites - intensive planes, such as higher cabin pressure, large windows and higher humidity.

Composites - intensive aircraft a "huge wake-up call"

“The decisions made in the past decade to build the first composite - intensive aircraft were a huge wake-up call for us,” admits Mick Wallis, President of Alcoa North American Rolled Products, who is responsible for Alcoa’s aerospace sheet and plate products.

“In hindsight it was the right decision for the time – when advanced aluminium solutions were not as developed – but our technology solutions have made quantum leaps since those decisions."

The new products apply to short-range aircraft.

“And it’s important to keep in mind that the mission requirements of short-range airplanes are dramatically different than those of longer-range planes,” adds Wallis. “With these new solutions we are confident we can add value to airframers in their short-range offerings, just as we have proven with longer-range planes … and the market research we’ve conducted says we are not alone in that belief.”

Alcoa claims that the combination of Alcoa solutions results in short-range aircraft that meet, or exceed, airframer targets for corrosion resistance, aerodynamic drag, maintenance requirements and fuel efficiency, along with improved buy-to-fly ratios. Alcoa says these improvements for a new short-range aircraft can generate up to a 12% increase in fuel efficiency on top of the 15% improvement from new engines.

Advanced alloys

The new solutions portfolio includes advanced alloys and third-generation aluminium lithium alloys that Alcoa says result in up to 7% lower density in major structural applications, along with critically important corrosion resistance.

Alcoa’s most-recent aluminium lithium alloys were selected for large commercial aircraft plate applications and are being used on planes about to enter the marketplace. These newest aluminium lithium alloys are said to provide additional enhanced performance.

Improvements in aerodynamics for skin sheet developed by Alcoa are reported to reduce skin friction drag by up to 6%. In addition, new structural technologies using forged, extruded and rolled products enable increased wing aspect ratio for improved fuel savings, provide up to 10 times more damage tolerance than conventional alloys, and allow increased cabin pressurisation for enhanced passenger comfort.

“As we began work on these new solutions, we wanted to ensure they contribute to all four phases of a plane’s life cycle,” reports Eric Roegner, President of Alcoa Forgings and Extrusions.

“In the first phase, when it is built, we will lower manufacturing and assembly costs and reduce programme risks for the airframer through established high volume supply chains and reduced investment requirements via existing infrastructure … and aircraft operators want the reduced risk associated with timely delivery."

“In the second phase, when customers fly the plane, the lower weight and aerodynamic technologies will increase fuel efficiency by up to 12% on their own and up to 27% when new engines are factored in,” he says.

“In the third phase, as airlines maintain the plane, we will lower costs because of enhanced corrosion resistance that helps with emerging inspection interval requirements."

"And, in the last phase – the end of life or retirement of the plane – aluminium’s infinite recyclability puts it head and shoulders above other materials in that it can be turned back into useful products again and again.”

Research findings

Alcoa conducted market research across the aircraft industry – including tier one players, airlines, maintenance/MRO and other leasing companies – to determine perceptions of choice for primary structure applications.

Alcoa reports that the more people understood the details, the more favorably they viewed aluminium for next generation aircraft structures versus composites. The research showed that nearly 3 out of 4 of the technical and design respondents surveyed had a favorable perception of aluminium as the primary structural material for new aircraft versus 54% for composites. Among management and commercial constituencies, the results showed the opposite.

When asked how likely they would be to recommend Alcoa’s solutions if they could deliver a 10% weight reduction, lower risk, and were 30% less expensive to manufacture, operate and maintain, 75% of respondents said they would recommend aluminium structures.