If previous incidents are any indication, however, the gaffe likely caused a sight to behold. Fire suppression systems used to protect military aircraft have been accidentally triggered numerous times in recent years, unleashing a sea of foam that can be difficult to control. In one case, the inadvertent triggering of a fire suppression system was fatal for a contractor who was engulfed by foam in a hangar.
A look at some other incidents:
Eglin Air Force Base 2014
The fatal incident at Eglin Air Force Base on Jan. 8, 2014, was the most serious. An Air Force investigation later found that temperatures around 30 degrees caused part of the suppression system to freeze, leading to a pressure buildup and the eventual activation of the foam.
Foam rose 17 feet high, “engulfing all but the very top of the vertical fins of the A-10, F-16 and three F-15 aircraft in the hangar,” the investigation found. The building was evacuated, but four civilian contractors re-entered through a third-floor cat walk, and then took an elevator down to the first floor of the hangar to exit the building, investigators found.
“Two of the contractors escaped the hangar within a few minutes and alerted on-scene emergency crews that two personnel were trapped in the hangar,” the investigative report said. “Rescue operations were begun immediately, ultimately resulting in the rescue of one of the two remaining maintainers. The final maintainer was pulled from the foam approximately 1 hour and 19 minutes after being submerged.”
The man was in cardiac arrest, the report said. Emergency personnel were not able to revive him.
Black Hawk helicopters buried at Tulsa hangar
As covered on Checkpoint, a Army National Guard hangar in Tulsa, Okla., was inundated with foam in August 2014 after an employee with a fire security company accidentally triggered the fire suppression system. A hangar was overwhelmed by foam, and it spilled out onto the flight line.
The hangar had at least six Black Hawks in it when the foam deployed, and at least two others outside also were affected. Most of the aircraft were quickly cleared to fly again.
Dover Air Force Base 2013
Foam was accidentally triggered at Dover Air Force Base in Delaware on Sept. 17, 2013, overwhelming a hangar with at least one aircraft inside. Fire personnel cleaned it up, spraying the foam with water to help dissipate it.
Eglin Air Force Base, 2012
As pointed out here on The Aviationist blog, foam had previously filled a hangar at Eglin in 2012 after a spark from a welder triggered the suppression system. In that case, an A-10, an F-15 and an F-16 were all submerged.
A 2000 report by the Naval Research Laboratory said that all branches of the military has been “plagued with false activations involving foam-water deluge sprinkler systems over aircraft with open cockpits.”
The activations were caused by a variety of incidents, including lightning strikes, accidental releases by maintenance personnel, deliberate acts of vandalism and roof water leakage into heat detection systems.
The foam quickly puts out actual fires while minimizing or preventing damage to multi-million dollar aircraft. Given the option between accidental discharges or the catastrophic loss of planes, it’s unlikely the Pentagon will change course anytime soon.