Airmen watch, record and gawk as fire suppression foam engulfs a maintenance hangar testing the installation’s high expansion foam discharge in the repair aircraft maintenance hangar April 8, 2015, at Fairchild Air Force Base, Wash. Tests like these are important as aircraft hangars, by their nature, pose unique challenges for the fire protection engineer. The hangar has large, open floor areas with tall roof decks to house Fairchild’s KC-135 Stratotanker. Large quantities of liquid jet fuel are present, and aircraft maintenance activities offer a variety of potential ignition sources. (U.S. Air Force photo/Staff Sgt. Benjamin W. Stratton)

Fire suppression foam engulfs a maintenance hangar as part of a test of the installation’s high expansion foam discharge in the repair aircraft maintenance hangar April 8, 2015, at Fairchild Air Force Base, Wash. The test allowed the installation to assess whether the system was capable of meeting essential milestones required for full certification including covering at least 90 percent of the aircraft’s silhouette and covering the entire hangar floor with at least one meter of foam within four minutes. This test proved the installation’s primary maintenance hangar is ready for most situations. (U.S. Air Force photo/Staff Sgt. Benjamin W. Stratton)

Capt. Gavin Johnson, 92nd Air Refueling Wing assistant staff judge advocate, uses his smartphone to capture fire suppression foam as it engulfs a maintenance hangar as part of a test of the installation’s high expansion foam discharge in the repair aircraft maintenance hangar April 8, 2015, at Fairchild Air Force Base, Wash. The test allowed the installation to assess whether the system was capable of meeting essential milestones required for full certification including covering at least 90 percent of the aircraft’s silhouette and covering the entire hangar floor with at least one meter of foam within four minutes. (U.S. Air Force photo/Staff Sgt. Benjamin W. Stratton)

Airmen watch as fire suppression foam engulfs a maintenance hangar testing the installation’s high expansion foam discharge in the repair aircraft maintenance hangar April 8, 2015, at Fairchild Air Force Base, Wash. According to the 92nd Civil Engineer Squadron, the main fire threat is posed by a fuel spill finding an ignition source, leading to a challenging fire. A 50 foot diameter pool of burning jet fuel can produce a heat release rate of nearly 300 megawatts. A few hundred gallons of ignited fuel is enough to destroy just about any facility that is not properly protected. This test proved the installation’s primary maintenance hangar is ready for most situations. (U.S. Air Force photo/Staff Sgt. Benjamin W. Stratton)