http://www.strategypage.com/htmw/htmurph/articles/20060418.aspx

The Truth About the Ellsworth Foam Monster
April 18, 2006: The U.S. Air Force is taking a lot of ribbing because of photos showing one of their hangers filling with fire suppressing foam. The pictures were from a test of the foam system conducted on August 23rd, 2005. The new foam system had just been installed, and had to be tested. The system had to be able to put down one meter (39 inches) of foam in four minutes or less. To that end, the system was allowed to generate foam for the full four minutes. It turned out that the system worked better than expected, practically filling the B-1B bomber with foam within four minutes. For the people working in the hangar, this was a good thing. A major accident could fill most of the hanger with smoke and flames within minutes. Knowing the foam system could outrun any fire or explosion, and save the lives of the people working in, or near, the hangar, was reassuring. But, let's face it, it was also funny as hell.

Pictures:
http://www.strategypage.com/military_photos/20064611181.aspx