Inert Gas System (IGS)
Inert Gas System (IGS)
An inert gas system, commonly using nitrogen, prevents fuel tank explosions in aircraft by displacing oxygen with a non-combustible gas, thus reducing the risk of combustion.
How it Works
Aircraft fuel tanks have a space above the fuel called the "ullage" that contains air and fuel vapors. This ullage can become flammable if the oxygen concentration is high enough. An inert gas system reduces the oxygen concentration in the ullage by replacing it with a non-combustible gas, like nitrogen.
Benefits
By reducing the oxygen concentration, the system makes it much harder for the fuel vapors to ignite, even if there is a spark or other ignition source.
Types of Systems
- Nitrogen Purging: Nitrogen is used to displace oxygen in the fuel tank, a process known as nitrogen purging.
- On-Board Inert Gas Generation Systems (OBIGGS): Some systems separate nitrogen from engine bleed air to create a nitrogen-rich environment in the fuel tanks.
Applications
Inert gas systems are used in both commercial and military aircraft to enhance safety and reduce the risk of fuel tank explosions.
Examples of Inert Gases
Besides nitrogen, other inert gases can be used, such as argon.
