Aircraft Sealant Application Process
May 1st, 2022
Aircraft sealants are essential for maintaining the quality and safety of aircrafts. These heavy duty adhesives are designed to reinforce and seal aircraft parts to improve the plane’s structural integrity and ensure it is safe for flight. Not only that, but sealants also help prevent against things like corrosion, fluid and dust intrusion, air leaks, and the spread of fire between compartments.
What are the Different Classes of Aerospace Sealants?Most aircraft sealants are subject to PMA (Parts Manufacturer Approval) and the standards set by the Federal Aviation Administration (FAA). Aircraft sealants are separated into different classes based of their viscosity. The three main classes of aircraft sealants include:
Class A Aircraft SealantsClass A sealants are a paste-like consistency and are applied by brushing. These sealants target fasteners in fuel tanks and other fuselage applications.
Class B Aircraft SealantsClass B sealants are a thicker, non-flowing consistency. These sealants are usually applied with an extrusion gun and are used for fillet and injection seals.
Class C Aircraft SealantsClass C sealants are thinner consistency than Class B, much like a liquid. These sealants are usually applied with a roller and are used for fay sealing when joining two overlapping surfaces.
Where are Aircraft Sealants Used?The sealant or adhesive you use will depend on what area of the plane it’s intended for. Sealants defined by their application include:
- Fuel Tank Sealants
- Cabin Pressurization Sealants
- Aircraft Window & Canopy Sealants
- Access Door Sealants
- Thread Sealants
- Firewall & Fuselage Sealants
How are Aircraft Sealants Applied?Sealant application requires both time and precision. Proper application ensures the aircraft adheres to necessary performance requirements and increases the service life of integral parts and components. Each sealant has its own unique application process, however; general sealant application guidelines are as follows:
- Remove existing sealant
- Mix the sealant
- Follow application instructions based on sealant type and target area
- Allow adequate time and temperature for sealant to cure