Aviation is under intense pressure to improve safety while cutting fuel use and emissions. Airlines and regulators demand higher fuel efficiency (to reduce carbon dioxide and operating costs) alongside stringent safety standards.
Composite materials have emerged as proven engineering solutions that deliver lighter, stronger airframes to meet these needs. They are already widely used in commercial airliners, defence aircraft, UAVs, and spacecraft.
Why are composites used in aircraft?
Because they combine high-strength fibres (such as carbon or aramid (Kevlar)) with a lightweight polymer matrix, giving structures a very high strength-to-weight ratio.
In practice, this means aircraft can be built much lighter without sacrificing structural strength or stiffness. The reduced weight directly translates into fuel savings, while composites’ natural resistance to corrosion and fatigue improves reliability and cuts maintenance needs.
What Are Composite Materials in Aerospace?
In aerospace, composite materials are engineered combinations of fibres and resins designed to maximise strength-to-weight, stiffness, and durability. At Advanced Composite Engineering, these materials are formed into precision components such as carbon and glass fibre tubes, sleeves, and structural profiles used in airframes, fuel-system components, spacers, and other weight-critical applications.
Composites consist of high-strength fibres embedded in a polymer resin matrix. The fibres (carbon, glass, or aramid) carry the loads and provide stiffness, while the resin binds the structure, transfers stress, and protects against environmental damage. This allows designers to achieve performance levels that metals cannot match at comparable weight.
Common types include:
- Carbon-fibre composites: Lightweight and extremely stiff, used in aerospace tubing, structural components, and applications where weight reduction and consistency are critical. Carbon-fibre orientation and layup can be tailored for specific load paths.
- Glass-fibre composites: Heavier than carbon but more cost-effective, offering good strength, corrosion resistance, and electrical insulation for secondary structures and internal components.
- Aramid (Kevlar) composites: Valued for toughness and impact resistance, suitable for applications requiring damage tolerance and energy absorption.
- Hybrid laminates: Combinations such as carbon and aramid allow engineers to balance stiffness and toughness within a single component for more demanding aerospace use cases.
How Do Composites Make Aircraft More Fuel Efficient?
Weight reduction
Reducing structural weight is the primary way composites save fuel. High-strength carbon and glass composites can be 20 – 40% lighter than equivalent aluminium parts, depending on the application. For example, aerospace-grade composite tubes often weigh 40 – 60% less than steel or aluminium tubes.
One review found that a 15 – 30% reduction in structural weight (from composites vs. metals) can translate to about a 20 – 25% improvement in overall fuel efficiency.
Using composites directly reduces fuel burn and thus CO₂ emissions. Lighter aircrafts need less thrust and fuel for the same mission, so a composite-rich airliner emits fewer emissions per passenger-kilometre. For example, Boeing estimates that the 787 Dreamliner (about 50% carbon composite) achieves roughly 20% lower CO₂ per flight than an equivalent all-aluminium aircraft.
Design freedom
Composites allow large, complex parts to be moulded as single pieces. This eliminates many joints, fasteners and overlaps (each of which adds weight and potential stress concentrations).
Fibres can be aligned along principal load paths, so material is placed only where needed. For example, a wing skin and spar might be made as one composite structure instead of riveted subpanels.
Fewer components and tailored laminates remove “inefficiencies” in the design, yielding further weight savings and more consistent performance over the aircraft’s life.
Aerodynamics
The seamless, smooth surfaces achievable with composites can reduce drag. Continuous fibres in a single moulded skin give a smoother finish (no rivet heads or stepped joints), and designers can fine-tune airfoil shapes with fewer geometric constraints.
For instance, composite manufacturing has enabled laminar-flow wing sections and blended winglets on some jets, reducing drag.
The fuel benefit depends on the overall aerodynamics: well-optimised composite shapes can significantly cut drag, but the effect varies with speed and flight profile.
Lifecycle efficiency
Composites resist corrosion and fatigue cracking better than metals. Aerospace polymers and fibres do not rust, so they often require less anticorrosion maintenance. Aircrafts like the Airbus have reported significantly reduced fatigue and corrosion-related inspections after switching to composites.
The long life of composite parts means fewer replacements and less manufacturing waste over time. However, these savings depend on manufacturing quality, fibre alignment, void-free lamination and proper curing, which must be carefully controlled.
Advanced production processes (like automated fibre placement) help ensure the intended performance is realised in service.
Question of Safety in Aircraft with Composites
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Strength-to-Weight
Properly engineered composite laminates offer extremely high tensile strength and stiffness for very low weight. Carbon fibres themselves are much stronger (per unit mass) than typical aerospace aluminium.
By aligning fibres with the load directions, a composite wing or fuselage can carry design loads with wide safety margins. In effect, a lighter composite structure can be just as safe as a heavier metal one, because the composite material can be much stronger than the same weight of metal.
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Fatigue and Corrosion Resistance
Unlike aluminium, composite materials do not corrode, so they eliminate cracking and pitting from corrosion. Composites also tend to tolerate cyclic loading well: when fatigue damage does occur, it often develops slowly (for example, matrix microcracks or delamination) and can be detected during scheduled inspections.
These traits make long-term behaviour more predictable. That said, composites are not indestructible: they still require routine non-destructive inspection (often ultrasonic) to find any subsurface damage.
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Impact and Damage Tolerance
Certain composite fibres (especially aramids) are extremely impact-resistant. Kevlar-based laminates, for example, are used in areas prone to bird strikes or ground handling damage.
These tough fibres can absorb impact energy without catastrophic failure.
Overall, a composite structure tends to crack or delaminate under severe impact rather than dent, so damage can be more difficult to see. Some internal delamination may not be visible externally.
Engineers compensate by adding extra plies of tough fibres in vulnerable zones (e.g. rotorcraft blades, leading edges) to improve damage tolerance and by employing advanced inspection techniques.
Fire Behaviour
Aviation-grade composites are engineered for fire safety, but they behave differently from metals. For example, aluminium will melt at about 660°C, whereas a carbon fibre composite will begin to char and hold structural shape as the resin burns off.
In many test conditions, composite panels maintain integrity longer under flame than aluminium ones, because the carbon fibres form an insulating char layer that slows burning.
They must meet stringent burn-through resistance standards, but they are not inherently fireproof.
Where Composite Materials Are Used in Modern Aircraft
Modern aircraft use composites in many areas. Common applications include:
- Wings and Control Surfaces: Wing skins, spars and fairings are often carbon composite. Control surfaces (ailerons, elevators, rudders) may use carbon- or glass-fibre laminates.
- Fuselage Sections: Fuselage panels and barrel sections are frequently carbon-fibre structures.
- Tailplane and Engine Nacelles: Horizontal and vertical stabilisers often use carbon composites for high strength at low weight.
- Fairings and Panels: Non-primary structures like aerodynamic fairings, wheel well doors and lightweight interior panels are often made of fibreglass or carbon composite to cut weight.
- Radomes and Antenna Covers: Radomes (the radar-transparent covers on the nose and antennas) are typically composite (often glass-fibre) because they must be electrically transparent yet durable.
- Interior Components: Some cabin components (floor beams, ceiling partitions, overhead bins) are now made from composite sandwich panels to save weight. Even seat frames and other furnishings can use carbon laminates.
- UAVs and Drones: Many unmanned aircraft use composite airframes (wings, fuselages, propellers) to maximise range and performance. eVTOL and hybrid-electric aircraft also rely on composites for weight-critical structures.
- Tubes, Sleeves and Profiles: Aerospace carbon-fibre tubes and sleeves are used for sensor housings, wiring conduits, fuel gauging equipment and structural spacers. For example, Advanced Composites supplies carbon-fibre tubes for aerospace sleeves, fuel-gauging equipment and other tubular components. These composite pipes offer weight savings and corrosion resistance for avionics and fuel systems.
- Defence Aerospace: In military aircraft and missiles, composites are used in rotor blades, missile bodies and structural frames. Advanced Composites has supported defence projects; for instance, our engineers provided a carbon-fibre launch tube for the NLAW anti-tank missile. In each case, composites are chosen where low weight and high performance are critical.
In Summary
Composites can make aircrafts more fuel efficient primarily by enabling aircraft weight reduction and more structurally efficient designs, which can translate into lower thrust requirements and reduced fuel burn across a mission. They can also support safety by improving corrosion resistance, offering different fatigue behaviour than metals, and allowing designers to tailor load paths through fibre orientation.
The practicality is that the benefits depend on:
- Engineering quality: load-path design, joints, damage tolerance assumptions, and correct allowables.
- Manufacturing precision: fibre alignment, consolidation/void control, cure quality, and process repeatability.
- Proper material selection: fibre type, resin system, and laminate design matched to environment, certification needs, and inspection strategy.
Composite materials for aviation are proven, but they reward precise engineering and precise manufacturing, and they penalise shortcuts.
Ready to Engineer Safer, Lighter, More Efficient Aircraft Structures?
If you’re considering composite materials for aviation, whether for a next-generation airframe, a weight-sensitive UAV platform, or specific aircraft sub-assemblies, the most useful next step is often a technical discussion around the realities: load paths, interfaces, inspection expectations, and what level of manufacturing control is required to achieve repeatable properties in service.
Advanced Composites Engineering works with aerospace and defence teams on composite tubular components where weight, durability and consistency matter, supporting applications such as aerospace composite tubing (including carbon sleeves, spacers and fuel gauging equipment) and holding product-specific aerospace approvals for certain items.
If you’d like to explore suitability for your project, you can speak with the technical team to:
- Request technical specifications for aerospace-grade carbon fibre tubes, sleeves, and structural profiles
- Discuss design optimisation and material trade-offs for safety-critical and fatigue-sensitive applications
- Review experience across aerospace and defence applications, including programmes where composite tube performance and reliability are central
When performance targets are tight, outcomes typically depend as much on material selection and process control as on the laminate itself. Speak with our composite specialists on 01670 335490 to discuss material choices, design trade-offs, and manufacturing considerations for your application.
You can also download our Composite Materials Glossary for a clear overview of key terms and material options used in modern lightweight engineering.
Frequently Asked Questions
1. Are composites better than aluminium in aviation?
Often, yes. Composites generally offer a higher strength-to-weight ratio and do not corrode like aluminium. This makes them preferable for many modern aircraft structures (such as wings and fuselages) where weight saving is critical. However, “better” depends on the application. Aluminium alloys still have advantages in damage tolerance, cost and repairability.
2. Do composites reduce maintenance?
Yes, because composites don’t rust and can have high fatigue life, they often require less routine maintenance. For example, Airbus reported fewer corrosion- and fatigue-related inspections on the composite A350 XWB. In general, a well-designed composite part can have longer service intervals than an equivalent metal part.
3. What parts of an aircraft use carbon fibre?
Carbon-fibre composites are used in primary airframe structures: wings, fuselage panels, tailplanes and control surfaces (like ailerons and rudders). Other applications include radomes, fairings, engine cowlings and interior structural panels. Many UAVs and future hybrid/electric craft also rely on carbon composite for their airframes.
4. Are composites as durable as metal?
Composites can match or exceed metal durability in many respects. For example, they won’t corrode and can be designed for excellent fatigue performance. Some aerospace thermoplastic composites endure a very high number of stress cycles. However, durability depends on environment and design: composites may be more sensitive to UV exposure or certain solvents than metals, and impact damage behaves differently.
