The use of nitrogen gas in aerospace applications has become increasingly common in recent years due to its inert properties and ability to reduce fire hazards. Nitrogen makes up about 78% of the Earth’s atmosphere, but it is an inert gas that does not support combustion. This makes it ideal for use in aviation and spaceflight where flammability is a major concern.

Use in Aircraft Systems 

In aircraft, nitrogen is used to inert fuel tanks and other flammable fluid systems. By displacing oxygen, nitrogen prevents combustion from occurring even if an ignition source is introduced. This dramatically reduces the chances of an explosion or fire. Nitrogen is supplied either from liquid nitrogen dewars or generated onboard using molecular sieves. The fuel tanks and dry bays of most modern airliners are filled with nitrogen-enriched air to prevent possible fuel tank explosions.  

Nitrogen is also used in scavenging systems on aircraft engines. It is used to flush volatile vapors from the turbine area and also to blanket the engine oil system. This protects against potential fires and explosions in the engine compartment.

Applications in Spaceflight

Spacecraft also rely heavily on nitrogen purging systems both pre-launch and in-flight. All stored propellants and fluids are saturated with nitrogen to eliminate any combustion risk. The inert nitrogen environment continues even during spacewalks. Astronauts breathe a nitrogen-oxygen mix in their spacesuits instead of pure oxygen. This protects against a scenario where a spark inside the suit could otherwise cause a fire. The nitrogen dilutes the internal atmosphere to below the point where combustion can occur.

Use in Rocket Propulsion Systems

In rocket engine design, nitrogen is used as a conditioning gas and also for purging propellant lines. Cryogenic propellants like liquid hydrogen and oxygen must be handled with extreme caution to avoid accidental ignition and explosions. Nitrogen gas keeps the propellant tanks and feed lines inert as they are loaded just prior to launch. It displaces any stray oxygen or combustible vapors.

Emerging Applications

Nitrogen gas generators are even being studied experimentally for inclusion onboard hypersonic vehicles. The extreme temperatures encountered at Mach 5+ speeds can potentially cause air to break down and release excess oxygen that could feed an engine fire. Nitrogen could be generated inflight to inert critical compartments for increased safety.

Ground Support Uses

The inert properties of nitrogen have also been applied extensively on the ground. Nitrogen is used to inert aircraft fuel tanks during maintenance and repair. Technicians can then safely work inside the tanks that would otherwise pose an explosion risk. Purging with nitrogen also protects against corrosion compared to using compressed air.  

In aerospace manufacturing, gloveboxes filled with nitrogen provide an inert environment for handling reactive substances like titanium and lithium. This prevents them from oxidizing and igniting when exposed to air. Nitrogen gloveboxes are also critical for safely working with explosives used in rocket propellants.

Forging Forward to A Safer Future with nexAir Nitrogen Products

The unique fire prevention benefits of nitrogen will ensure it remains an indispensable part of the aerospace industry. As aviation and spaceflight continue advancing into the future, nitrogen’s role in enhancing safety and reducing accidents will only increase. At nexAir, we are poised to meet the growing demand for industrial grade nitrogen in aerospace applications. Engineers are certain to develop more innovative new ways to apply this readily available inert gas. 

With the ongoing risk of fires and explosions, nitrogen will remain an essential tool for protecting aircraft, spacecraft, and the humans onboard. nexAir will be ready to provide the high-quality nitrogen needed to reduce hazards and forge ahead to a safer future in the skies.