Whether it’s cutting-edge composites, various metal alloys, or even plywoods, we know that to stay competitive in the Light Sport and Light Aircraft segment you need suppliers that can get you custom, precision-cut parts in record time.
In this article we’ll look at a broad range of materials used in the experimental aircraft market, what’s new, what’s tried-and-true, and how SendCutSend can help get you the materials you need when you need them.
What to Consider when Selecting Materials for your Aircraft
Weight & Balance
Weight directly influences fuel efficiency, maneuverability, takeoff and landing distances. Every ounce saved contributes to better handling, increased range and improved payload capacity.
The need for proper balance fore and aft, as well as side to side, means materials must be chosen in such a way that even when assemblies aren’t symmetrical along a centerline, their overall masses are similar.
Cost
Although aircraft are generally considered an expensive investment, their complexity means that per component cost is a significant factor for manufacturers and buyers alike. When considering expensive raw materials for airframes or other large structural components, bringing those costs down can improve end-user accessibility and market competitiveness.
Design
While a panel van allows for great utility and interior space, its aerodynamics aren’t much to write home about, therefore the designer must ensure aerodynamic efficiency, durability/structural integrity, and even things like ergonomic comfort for pilots and passengers.
Manufacturability & Scalability
A hand-laminated and vacuum bagged fuselage may be the perfect solution for the hobby ultralight builder, but time and quality control constraints make it important to select materials and processes that will scale well and allow for consistent manufacturing results time after time.
Maintenance Requirements
Easy access to components for inspection, repair, and replacement is essential for both safety and reducing maintenance costs. Prefabricated control surfaces and hinged cowlings become valuable features, allowing for quick pre-flight checks and reducing the need for specialized tools.
Material Compatibility
Lightweight materials often have specific requirements for adhesives, sealants, and coatings to ensure they bond properly and last. For instance, using epoxy specifically formulated for composite materials ensures a strong and lasting bond between carbon fiber components, whereas using the wrong type of adhesive could lead to structural failure.
Strength and Durability
Despite being lightweight, the aircraft needs to be robust enough to withstand the elements and the stresses of flight. Material selection and design play a critical role here. Aircraft aluminum, for example, offers a good balance between weight and strength, while composites like carbon fiber can provide exceptional strength-to-weight ratios but require careful handling and proper repairs.
- Corrosion Resistance: Like any vehicle, aircraft are often exposed to the elements – rain, sun, and humidity – so corrosion resistance is a major factor in material selection. Aluminum, Composites and Stainless Steel are some of the more popular choices in this vehicle category.
- Fire Resistance: Fire-resistant additives can be incorporated into resins during manufacturing to improve composites’ fire resistance. Additionally, strategic placement of non-combustible materials like firewalls around the engine compartment help mitigate fire hazards.
- Temperature Resistance: Because of the cold temperatures at high altitude, aircraft must be designed to operate outside the normal range for land based vehicles.
Regulatory Compliance
Experimental Aircraft must meet specific safety standards set by aviation authorities like the FAA. Designing and building within these regulations is crucial for airworthiness certification. This may involve incorporating features like landing gear with specific strength requirements, or ensuring adequate control surface travel for safe maneuvering.
Supply Chain Availability
Finding high-quality materials that are readily available is key for builders and for keeping maintenance costs manageable. Disruptions in the supply chain can cause delays in building new experimental aircraft or drive up the price of replacement parts. For this reason, builders often favor materials like aluminum or wood, which are well-established and generally have a stable supply.
Top Metals for Experimental and Ultralight Aircraft Builds
Although we tend to think of experimental aircraft as mysterious and complicated. In fact, because of the rigorous certifications for aviation equipment, and the need for a lightweight and reliable end product, light and ultralight aircraft tend to be pretty straightforward compared to other vehicle categories.
This relative simplicity means that many of the same materials have been used in aircraft manufacture for at least the last 50 years. Let’s take a look at several material categories, and how and why they’re commonly used, and what challenges a midsized builder might face sourcing them.
Aluminum
By far the most popular build material for modern aircraft in nearly every category, SendCutSend offers aluminum in several grades for any aircraft application.
- 2024 T3 is the rimary alloying elements are copper & magnesium, making a ductile metal which offers a good balance of strength and weight. It’s low cost and excellent corrosion resistance make it a good choice for larger assemblies:
- Wing skins and spars
- Fuselage longerons
- Bulkheads
- 5052 H32 is an alloy of magnesium and aluminum that prioritizes formability, corrosion resistance and weldability. Applications include:
- Non-structural parts like fairings and other aerodynamic parts
- Fuel tanks due to good corrosion resistance
- Ductwork because it’s easily formable and bendable
- 6061 T6 is a versatile alloy that offers higher strength, with good machinability, and corrosion resistance. It is also heat treatable for added strength.
- Landing gear components
- Control surfaces like ailerons, rudders, and elevators
- Machined parts like brackets, fittings and fasteners
- 7075 T6 is a high-strength aluminum-zinc alloy tends to be used where maximum strength and fatigue resistance is needed:
- Wing spars, especially for larger aircraft
- Fuselage longerons in high-performance aircraft
- Helicopter rotor blades
Stainless Steel
Although Stainless Steel is much heavier than aluminum, its superior resistance to corrosive environments (salt water in particular) and very high strength/ductility mean it finds itself incorporated someplace in most aircraft builds. SendCutSend offers the two most common grades:
- 304 Stainless Steel is affordable, high-temperature and stress resistant. Applications include:
- Exhaust shrouds and stacks
- Fairings, enclosures and firewalls
- General hardware and cabling exposed to the elements
- 316 Stainless Steel offers superior corrosion resistance, especially to saltwater, making it ideal for:
- Seaplane components exposed to seawater
- Exhaust systems in high-performance engines
- Fasteners and hardware in critical areas where corrosion resistance is essential, such as engine mounts, landing gear, and control surfaces
Steel
Steel offers high strength and availability but is heavier than aluminum and doesn’t offer the corrosion resistance of stainless so its use is limited to areas where weight is less critical or strength is paramount.
- 4130 Chromoly is a chromium-molybdenum alloy steel known for its good strength-to-weight ratio compared to other steels. Applications include:
- Landing gear components: Needs to handle significant impact and weight loads.
- Engine mounts: Must be strong enough to support the weight and vibrations of the engine.
- High-stress fuselage structures in some light aircraft: Offers a balance of strength and weight for specific designs.
- AR400 is a High-Strength Low-Alloy (HSLA) steel which offers good abrasion resistance and 3x the strength of mild steel.
- Skid plates used to protect the underbelly of the aircraft from rough landings
- Cargo floor reinforcement
- AR500 has even higher tensile strength than AR400 and is through hardened for extreme abrasion resistance.
- Ballistic protection panels and components in specialized aircraft
- Galvanized Steels (G30 & G90) are steel sheets with a zinc coating for corrosion resistance. Applications are very limited in aircraft due to weight, but are an alternative to stainless steel when cost is a factor.
- Non-structural parts exposed to weather
- May be used for some corrosion-prone hardware (washers, nuts, bolts)
- Mild Steel is the workhorse of industry, a low-carbon steel with good machinability but lower strength compared to other steels on this list.
- Simple brackets or machined parts in non-critical areas
Titanium
Although the relatively high cost of titanium limits universal use in aircraft manufacture, due to its high strength-to-weight ratio, corrosion resistance, and ability to withstand high temperatures it is an ideal build material for experimental aircraft components. We offer the two most popular grades in several different thicknesses to fit many aircraft applications:
- Grade 2 Titanium is often used in the construction of airframe components such as fuselage frames, wings, and stabilizers. Its high strength and corrosion resistance allows it to be used in place of stainless steel for fasteners, while its ductility makes it a good candidate for exhaust and hydraulic systems.
- Grade 5 Titanium, also known as Ti-6Al-4V, is widely used in the manufacturing of critical engine components such as compressor blades, turbine discs, and exhaust system parts. This Titanium grade is also used in structural components, landing gear and, because of its excellent thermal conductivity, heat exchangers.
Brass & Copper
While brass and copper aren’t primary structural materials in aircraft due to their weight, they offer good electrical conductivity, corrosion resistance, and machinability.
- Brass is an alloy of copper and zinc, offering good machinability, wear resistance, and corrosion resistance.
- Bushings and bearings: Brass provides good wear resistance in landing gear components, flight control systems, and door mechanisms.
- Certain instrumentation components such as pressure gauges, temperature sensors, and flow meters benefit from its machinability to tight tolerances.
- Copper is a highly conductive and corrosion-resistant metal known for its excellent electrical and thermal properties.
- Electrical wiring: Excellent conductivity makes copper ideal for electrical systems throughout the aircraft.
- Heat exchangers make use of copper’s thermal conductivity for efficient heat transfer in oil coolers and other systems.
- Copper is often used as a base material for brazing and soldering applications in aircraft manufacturing.
Optimal Uses for Metal Materials in Experimental Aircraft
| Metals | Fuselage | Wings | Empennage | Interior | Other Components |
| Aluminum | ✅ | ✅ | ✅ | ✅ | ✅ |
| Stainless Steel | ✅ | ✅ | ✅ | ||
| Steel | ✅ | ||||
| Titanium | ✅ | ✅ | ✅ | ✅ | ✅ |
| Brass | ✅ | ||||
| Copper | ✅ |
| Metals | Laser Cutting | CNC Routing | Waterjet Cutting | Anodizing | Offered by SCS |
| Aluminum | ✅ | ✅ | ✅ | ||
| Stainless Steel | ✅ | ✅ | |||
| Steel | ✅ | ✅ | |||
| Titanium | ✅ | ✅ | |||
| Brass | ✅ | ✅ | |||
| Copper | ✅ | ✅ |
Best Composite Materials for Building Experimental Aircraft
Composite materials are made by combining two or more distinct components, often a reinforcing fiber (like carbon fiber or fiberglass) and a resin binder. In experimental aircraft builds, composites are prized for their incredible strength-to-weight ratio.
Composites also allow for the creation of complex shapes and structures that are impractical with traditional materials like aluminum or steel. This flexibility enables experimental aircraft builders to push the boundaries of innovation and explore new technologies and design concepts while maintaining structural integrity and safety. Below is a breakdown of the best composites for building experimental aircraft.
Carbon Fiber
The darling of the composite world, new automated layup techniques and advanced resins mean carbon fiber is stronger, more versatile and production ready than ever before. It is commonly employed in constructing structural components such as fuselage frames, wing spars, control surfaces and aerodynamic components, contributing to improved performance and fuel efficiency.
G10/FR-4 Fiberglass
G10/FR-4, a type of fiberglass epoxy laminate, is chosen in light aircraft for its strength, stiffness, and good electrical insulating properties. It’s often used for non-structural components. This can include things like control surface brackets, bushings, spacers, instrument and electrical panels.
AMC Panel
ACM DiBond® panels can be used in experimental aircraft builds for their lightweight, durable, and versatile properties. These panels typically consist of two thin aluminum sheets bonded to a solid polyethylene core, providing high strength and stiffness while weighing roughly half that of a standard aluminum sheet. In aircraft construction, ACM panels may be employed for interior cabin panels, bulkheads, fairings, or non-structural exterior components.
Cork
While cork sounds like an unlikely building material for airframes, its compressibility and vibration dampening characteristics make it a potential material for gaskets, seals, and even sound insulation. Use of naturally sustainable cork to replace PVC and foam core composite layups is also underway.
LE Phenolic
Linen grade LE (Laminated Epoxy) Phenolic is a very dense, abrasion resistant, machinable composite material composed of resin and cotton cloth. In older aircraft (and their restoration today) it was used in a number of applications from electrical insulation, to bushings, rudders and even propeller blades.
Optimal Uses for Composite Materials in Experimental Aircraft
| Composites | Fuselage | Wings/Tail | Interior | Controls | Other |
| Carbon Fiber | ✅ | ✅ | ✅ | ✅ | ✅ |
| G10/FR-4 | ✅ | ✅ | ✅ | ||
| ACM Panel | ✅ | ✅ | |||
| Cork | ✅ | ✅ | |||
| LE Phenolic | ✅ | ✅ | ✅ |
Best Plastic Materials for Building Experimental Aircraft
Plastics are used extensively in experimental aircraft production for both interior and exterior components. They are commonly used for manufacturing cockpit panels, instrument bezels, fairings, windows and cabin trim due to their lightweight, durable, and customizable nature.
ABS
ABS is a common thermoplastic known for its affordability, ease of fabrication, and decent strength-to-weight ratio compared to other plastics. Used for manufacturing interior and exterior components such as cockpit panels, instrument bezels, fairings, and cabin trim, ABS can be molded into complex shapes, resists impact and weathering, and is cost-effective.
Acrylic
Acrylic is a transparent thermoplastic known for its clarity, durability, and weather resistance that has been used in aircraft manufacture since just prior to WWII as a lightweight replacement for glass. In experimental aircraft production, acrylic is still commonly used for manufacturing windows, canopies, and windshields. Its optical clarity provides excellent visibility for pilots, while its lightweight nature and resistance to impact make it suitable for aircraft applications. Additionally, acrylic plastic can be easily formed and shaped into aerodynamic profiles.
Polycarbonate
With its higher strength-to-weight and impact resistance, polycarbonate is often chosen over acrylic for use in aircraft windows. However, it is slightly less clear, more difficult to form and more expensive, meaning large canopies still often rely on laminated acrylics. For impact resistance, however, polycarbonate is the best option.
Delrin
Delrin® is a dense thermoplastic that can withstand high loadings, is easily machinable with good tolerances, and is resistant to gasoline and other solvents/oils. This makes it a good fit for various components such as bushings, bearings, control cable pulleys, and other mechanical parts.
HDPE
HDPE or High-Density Polyethylene is yet another thermoplastic sometimes known as “plastic wood” for its impact resistance, ease of fabrication and low cost. These attributes contribute to its popularity in experimental aircraft construction, particularly for non-critical interior components where strength is not a primary concern.
UHMW
Ultra-High Molecular Weight Polyethylene differentiates itself from the other plastics in this list primarily because of its low friction and incredible wear resistance. UHMW is commonly used for manufacturing components such as wear strips, bushings, bearings, and sliding surfaces. Its excellent self-lubricating properties reduce friction, leading to smoother operation and increased longevity of moving parts.
Optimal Uses for Plastic Materials on Experimental Aircraft
| Plastics | Fuselage | Wings/Tail | Interior | Controls | Other |
| ABS | ✅ | ✅ | |||
| Acrylic | ✅ | ✅ | |||
| Polycarbonate | ✅ | ✅ | |||
| Delrin | ✅ | ✅ | |||
| HDPE | ✅ | ✅ | |||
| UHMW | ✅ | ✅ | ✅ |
Wood/Boards
Although modern materials have replaced wood in nearly every aircraft application other than as aesthetic trim, wood still plays a significant role in aircraft restoration and fixturing, offering both structural support and affordability. Birch plywood is often employed in fabricating wing ribs, fuselage bulkheads, and firewalls, providing the necessary strength without adding excessive weight. Chipboard, hardboard and MDF are useful for patterns, jigs and fixturing, offering a cost-effective solution while maintaining durability.
FAQ
What are the most common materials used in experimental aircraft builds?
- Aluminum Alloys: Aluminum has been a staple in aircraft construction for decades due to its excellent strength-to-weight ratio, and corrosion resistance. Alloys like 2024 T3 and 7075 T6 series are workhorses for the fuselage, wings, and other structures.
- Composite Materials: New aircraft designs rely heavily on composite materials, especially Carbon Fiber Reinforced Polymer (CFRP). CFRP offers incredible strength-to-weight ratios, making aircraft lighter and more fuel-efficient. It’s increasingly used for wings, fuselage panels, and other major structures.
- Titanium Alloys: For parts that need exceptional strength and are resistant to high temperatures, titanium alloys are the first choice. Although more dense than aluminum, they typically have a greater strength-to-weight ratio. They find use in landing gear, engine components, and areas exposed to extreme heat.
Where can I find these materials for my next aircraft build?
Funny you should ask! SendCutSend supplies aluminum, composites including carbon fiber, and titanium, along with dozens of other materials.
What resources are there for me to learn more about the right materials?
Each of the materials we offer has a “Material Details” section on its webpage that lists material properties, what services you can add, bending, tapping, hardware, and laser cutting guidelines, and plenty more. For inspiration, head to our Examples page, and for way more informational content, take a look at our Guidelines and everything else in the Resources tab.
Conclusion
With the light and ultralight aircraft sector set to nearly double in the next five years, whether you’re positioned as a mid-size supplier, a kit plane company, or a light experimental aircraft builder, there is an increasing demand for parts and whole aircraft driven by both travel/tourism and individuals looking for mobility options.
Meanwhile, with the supply chain and geopolitical issues facing nearly every industry, it’s critical that you have reliable options to keep your customers happy. SendCutSend’s wide range of materials and capabilities set us apart from other raw material suppliers, and you can count on transparent pricing, always in-stock materials and fast shipping every time you upload a part to our app.
