Adequate control of the environment inside an aircraft ensures the comfort of the passengers and flight crew. Fuselage skin temperatures can range between –60°F when in flight to 160°F when parked in direct sunlight, threatening the cabin’s internal temperature. Additionally, the aircraft’s engine and the aerodynamics of flight generate a considerable amount of noise, causing discomfort for passengers and crew if proper insulation is neglected.

Thermal Acoustic Materials

As such, the FAA requires thermal and acoustic insulation for almost all commercial aircraft. These insulating materials ensure that external temperature changes do not negatively affect the passengers’ comfort and that excessive noise generated by the aircraft does not disrupt communication in the passenger cabin and on the flight deck. We provide state of the art materials which address the noise path between the sound source and noise receiver. Our materials combine sound blocking, sound absorption and sound dampening to produce the greatest reduction in unwanted noise and improve transmission loss at various frequencies.

Thermal acoustic insulation shields against excess noise and temperature in most aircraft. Thermal acoustic insulation layers the aircraft’s entire fuselage, and it consists of a specialized high-performance fiber encapsulated in an aircraft-rated plastic covering, holding the insulation material together while acting as a moisture barrier.

What to Know About Thermal Acoustic Materials

In addition to thermal- and acoustic-insulating functions, thermal acoustic materials must protect against fire and other incidents. The prevalence of insulation makes it a target for in-flight fire ignition, and flammable insulation can act as a path for flame propagation and growth. It is therefore essential that these insulation materials incorporate flame-retardant properties. Furthermore, since thermal acoustic material lines the fuselage body, it must also act as a barrier against fuselage penetration by external post-crash fuel fires, known as burn-through.

The aerospace and aviation industry also has demanding specifications on how much the material should weigh. Manufacturers typically prefer lighter weights to ensure desirable flight dynamics and fuel efficiency. Therefore, thermal acoustic materials must be relatively lightweight compared with the weight of existing systems, which average about 0.1 lb./sqft.

In addition to these properties, materials used in the construction of thermal acoustic insulation must not:

  • Interact negatively with the aluminum fuselage structure (i.e., corrosion).
  • Impede inspection of the fuselage structure for corrosion, cracks, and other issues.
  • Conduct electricity.
  • Absorb large amounts of moisture.
  • Have adverse health or environmental effects during fabrication, installation, or service.

Testing Requirements

Two industry standards primarily determine how thermal acoustic insulation is built:

  • FAR AC 25.856-1A – Thermal/Acoustic Insulation Flame Propagation Test Method Details
  • FAR AC 25.856-2A – Installation of Thermal Acoustic Insulation for Burn-through Protection

AC 25.856-1A describes a relatively new form of testing known as radiant panel testing. Radiant panel testing measures the tendency of thermal acoustic insulation to propagate fires from an in-flight ignition source.

AC 25.856-2A determines the burn-through resistance of thermal acoustic insulation from an external fuel source during a post-crash fire.

The FAA requires that all thermal acoustic insulation meets the requirements of these two regulations. These regulations use the following standard terms to describe the various aspects required for thermal acoustic insulation systems:

  • Overlap: The length of insulation material that extends to create a double thickness against the airplane skin or other abutting structure.
  • Capping strip: Lining material that covers the insulation overlap.
  • Thermal acoustic liner: Material that provides thermal and acoustic insulation.
  • Fuselage skin: Inner surface of the aircraft body.
  • Frame: Structural member that provides a surface for the overlap and facilitates fastening of the liner periphery.

Your Next Insulation Solution

Tex Tech’s extensive knowledge of high-performance materials and fiber blending enables us to design thermal acoustic liner materials that meet or exceed FAA regulations.

We tailor our insulation products to meet the individual requirements of each customer, and our products fit the ceilings, walls, and flooring systems of almost any type of aircraft. To learn more about our aerospace solutions, start by downloading our data sheet here.

Download the Aerospace Solutions Data Sheet

Download our guide today for a handy cross-section with insight into how and where our fire-blocking materials are implemented throughout an aircraft.

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