New Material for Aircraft Wings Could Lead to Reduced Fuel Consumption
26 September 2007
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| The CentrAl construction. Click to enlarge. |
A new special aluminum-fiber combination material (Central Reinforced Aluminum, CentrAl) for aircraft wings that makes them nearly immune to metal fatigue could contribute significantly to lower fuel consumption by reducing the weight of conventional constructions.
Fatigue is a phenomenon that affects materials after long-term exposure to cyclic loading. As a result of varying loads, fractures eventually occur. The new CentrAl constructions are stronger than the carbon fiber reinforced plastic (CFRP) constructions that have recently been used in aircraft wings such as the Boeing 787. By using CentrAl wing constructions, the weight can be reduced by 20% compared to CFRP constructions. Furthermore, using CentrAl results in considerably lower manufacturing and maintenance costs.
The CentrAl concept comprises a central layer of fiber metal laminate (FML), sandwiched between one or more thick layers of high-quality aluminum. This creates a robust construction material which is not only exceptionally strong, but also insensitive to fatigue. The CentrAl technique enables simple repairs to be carried out immediately, as is the case in aluminum constructions, but not the case when using CFRP constructions.
This patented new concept is one of the results of a collaboration between the company GTM Advanced Structures, founded in The Hague in 2004 and specializing in new aircraft materials and constructions; Alcoa; and the Faculty of Aerospace Engineering of Delft University of Technology.
GTM and Alcoa presented the new concept to international experts in the field of metal fatigue and damage sensitivity of aircraft constructions at a conference in Delft (Conference on Damage Tolerance of Aircraft Structures: 25-28 September 2007).
The US Air Force, Alcoa and GTM will also discuss the possibilities for the use of the new CentrAl material to create ‘Carefree structures’. These are aircraft constructions that are less sensitive to damage caused, for example, by fatigue, hail storms, other weather phenomena, trucks that collide with the aircraft and corrosion. Carefree aircraft constructions will be characterized by significantly reduced maintenance costs.
Could this material also make the wings for wind-power cheaper and better ?
Posted by: Alain | 26 September 2007 at 08:02 AM
Could this material be used in the Airbus A350XWB - or is it too undeveloped ?
Probably too expensive for normal cars, though.
Posted by: mahonj | 26 September 2007 at 08:28 AM
This could be another win-win product.
What would be the total impact on fuel consumption, GHG and air pollution?
Wonder how long it will take to become common usage in various applications such as aircraft, vehicules, windmills blades etc.
The new challenge created by liquid fuel shortage, climate warming, increasing GHG and unhealty air pollution will be positive in the mid and long term.
Posted by: Harvey D | 26 September 2007 at 08:43 AM
What does this do for the million flex strength for the aluminum? Does this make it equivalent to steel in that as long as you don't go into plastic deformation it is considered to last forever?
I might be stating these questions wrong as I am not a ME.
Posted by: Patrick | 26 September 2007 at 08:49 AM
Patrick
Reading between the layers (?) this is a composite which is going to fail gracefuly. The basic physics of the materials has not been changed - the aluminium will still fatigue, one layer at a time with no crack propogation between layers because they are separated by other materials. It'll get checked (at longer than previous intervals) and damaged layers will be identified before failure is catastrophic
I like this kind of slightly exotic material development - but until the petrolheads find lightweight materials and transport system efficiency exciting (and want to pay for it) then we may not have see the end of the (remarkably effective) pressed/welded steel car for a while (sigh).
But I'm not an ME either
Posted by: Rob Weir | 26 September 2007 at 09:40 AM
Mahonj - At the rate Airbus has been going the last few years, they'll have the A350 fully designed by about 2025. That'll give Boeing time to prove the material out on their next couple of generations of aircraft...so yeah, it should be ready to go for the A350. :)
Posted by: Matthew | 26 September 2007 at 10:43 AM
Boy! what a great material for airstream trailers! Seriously, this is a great material and no doubt will find use in new aircraft products. Like Helicopters, small jets, etc.
Posted by: Lad | 26 September 2007 at 11:42 AM
Fibre-metal laminates are already widely used on the A380; a material called 'Glare' originally developed sometime in the 1970's.
What's new here seems to be that the inner layers are much thinner.
Posted by: jb | 26 September 2007 at 12:48 PM
It'll be interesting to see what Boeings response to this will be, especially in the long run.
Posted by: Bob | 26 September 2007 at 01:24 PM
Alan,
I’m no engineer, but I’m thinking that blade weight reduction is not an issue for the props on windmills. Some mass dampens the variability in the rate energy is delivered from the drive system which is trying to produce, as close as possible, a steady RPM to the generator.
Posted by: WhiteBeard | 26 September 2007 at 04:57 PM
Alan,
I’m no engineer, but I’m thinking that blade weight reduction is not an issue for the props on windmills. Some mass dampens the variability in the rate energy is delivered from the drive system which is trying to produce, as close as possible, a steady RPM to the generator.
Posted by: WhiteBeard | 26 September 2007 at 04:58 PM
Progress, Isn't it wonderful?
Posted by: Stan Peterson | 26 September 2007 at 07:16 PM
The question in my mind is about fabrication, would it come in sheets like aircraft skin does now, to be cut and riviteted together or does each piece need to be custom molded to fabricate?
Posted by: A.Syme | 26 September 2007 at 08:39 PM
Very ingenous idea! Kinda like making the resiliency of fiberglass from the very brittle amorphous solid glass itself.
Of course, aluminum is far more resilient than glass, and lighter than carbon-fiber or fiberglass composite structure, with much better electrical conduction in the case of lightning protection for aircraft.
Posted by: Roger Pham | 26 September 2007 at 11:17 PM
Whitebeard...You're right on the dampening effect of weight. But I just took a pic of these huge wind blades on the ground at an Oregon site construction zone next to a full size stretched pickup. The center hub dwarfs the truck, the angled blade width nearly makes the truck disappear & WOULD make the truck disappear, but then there would have been no size comparison.
Surely, any weight reduction of these monster blades would ease the pressure on hub bearings more so than the dampening weight helps.
Posted by: litesong | 28 September 2007 at 08:05 AM
This new material could be the thing for the Boeing 737RS (the successor to the current 737 models) and the Boeing Y3 (the successor to the 777 models).
Posted by: Raymond | 29 September 2007 at 09:31 AM
I thought Airbus already have such composite material on the A380. Instead of carbon fiber, the airbus uses glass fiber and aluminium sandwich.
I guess Boeing solved the accelerated corrosive problem found in carbon+aluminium sandwich.
The basic concept this, the fiber deals very well with tension load (better than metals), and the aluminium deals with the compressive load and conductivity (so that it is lightning safe).
Posted by: Chin | 10 October 2007 at 06:01 AM
How is this particularly different from widely used aluminum honeycomb?
Posted by: jp straley | 29 February 2008 at 04:00 PM
How is this particularly different from widely used aluminum honeycomb?
Posted by: jp straley | 29 February 2008 at 04:00 PM