The FAA has recently concluded flight tests on both an A320 and a NASA 747, of a simplified OBIGGS system for fuel tank inerting. The following FAA .pdf reports discuss the OBIGGS system design used on each aircraft, flight test parameters, and test results. They are interesting reading for anyone interested in the current state-of-the-art in on-board nitrogen gas generation fuel tank inerting systems.

Airbus A320 flight test results - June 2004 - 1.25MB

NASA 747-100 flight test results - December 2004 - 8.8MB

and they have just issued Special Conditions for a 747 Flammability Reduction System:

http://www.airweb.faa.gov/Regulator...1C?OpenDocument

All these lengthy links are accessible via this link www.iasa.com.au/obiggs.htm   (this page)