The Advanced Life Support System (ALSP) was taken up to match the state-of-the-art systems by employing innovative and advanced technologies for enhancing combat efficiency of pilots flying fighter aircraft and helicopters. Under the project, prototypes have been realised and technologies like On-Board Inert Gas Generation using polymeric hollow fibre membranes, High Purity Oxygen Concentrator using Zeolite and advanced carbon molecular sieves, Electronic Demand Breathing using miniature sensors and actuators, Oxygen Sensing using miniature Zirconia sensor element based on Amperometric and Tunable Diode Laser-based Absorption Spectroscopy (TDLAS) principles, enhanced protective equipment— Advanced Anti G Suit, Lightweight Helmets having advanced visor locking mechanism have been demonstrated.

On-Board Inert Gas Generating System (OBIGGS)

An On-Board Inert Gas Generation (OBIGG) system is now mandatory for many civilian and military aircraft to prevent the buildup of explosive conditions in fuel tanks by generating Nitrogen Enriched Air (NEA) to lower the oxygen content in the fuel tank headspace or ullage.

Aircraft fuel tank fire protection has been the focus of intensive research for many years because of the importance of protecting the crew and increasingly valuable assets against fuel tank fires and explosions. Without a protection system, the fuel/air mixture in the fuel tank ullage is susceptible to ignition due to combat damage, lightning, electrostatic discharges and electrical arcing resulting from equipment malfunction. To mitigate the potential for a catastrophic fuel tank ullage explosion, it is necessary to reduce the oxygen concentration from the 21 percent that is present in a standard volume of air to 9.8 percent at sea level when inerting fuel tank ullage with nitrogen gas. This provides the aircraft and its crew with the necessary protection from an enemy threat of up to and including 23 mm high explosive incendiary rounds.

OBIGGS is a full-time inert gas generation system based on hollow fibre membrane systems. Membranes separate gases by the principle of selective permeation across the membrane wall. The OBIGGS utilises cooled engine bleed air as the air source and then separates the inlet air into a nitrogen-enriched product air stream and a slightly oxygen-enriched vent stream (through a physical and not chemical based process). The vent stream is then routed either overboard or into an unpressurised bay to maximise the effectiveness of the OBIGGS system. The OBIGGS approach has significant advantages in that it will provide an aircraft fuel system with continuous and unlimited supply of nitrogen gas while being maintenance free.

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