Air Force Research Laboratory technology results in improved firefighting vehicles

  • Published
  • By Adriana Casarez
  • Materials and Manufacturing Directorate
Air Force Research Laboratory Materials and Manufacturing Directorate Airbase Technology Division scientists at Tyndall Air Force Base, Fla. have developed ultra high pressure water firefighting technology that will result in smaller, leaner and air transportable fire trucks. Starting in Fiscal Year 2008, these new trucks can be deployed in sets of two on a C-130, whereas the former fire truck could only be carried one at a time aboard the Hercules aircraft.

"In the area of Fire Protection, the Air Force needs a fire truck that is designed to be reliable, lightweight and compact," explained Virgil Carr, the fire research program manager. "The Air Force currently uses the standard P-19 fire truck which has great difficulty when deployed because it doesn't easily fit into a C-130 aircraft. In order to transport it, the roof turret must be removed and then reattached when it's back on the ground.

According to Carr, in the late 1990's, the AFRL Fire Research Group at Tyndall Air Force Base, Florida, began a program to develop technologies that enhanced the performance of current firefighting technology. Initial efforts were directed towards developing a single system that would address both two-dimensional flowing fuel fires (pool fires) traditionally fought with Aqueous Film-Forming Foam (AFFF), and three-dimensional fires (flowing fuel fires) fought with Halon 1211, an agent that changes from liquid to gas during application. AFFF works by forming a barrier between the fire and fuel surface preventing the flame from spreading. The initial approach showed great potential; however, it resulted in an unacceptably expensive system.

"This research has led to revolutionary concepts in firefighting equipment and firefighter technique and strategy, including ultra high pressure (UHP) water technology," Carr said. "In September 2002, scientists began research on the use of UHP technology for extinguishing hydrocarbon fuel fires. In 2003, a major breakthrough occurred when (Materials and Manufacturing Directorate) developed an air-deployable All Terrain Vehicle with a mounted UHP system."

This apparatus, referred to as the First Response Expeditionary vehicle, was the initial UHP system developed by the Fire Research Group and currently is the only firefighting asset capable of being dropped from an aircraft in the Air Force inventory. It has been commercialized and can be bought from Rosenbauer America. UHP technology has proven to be greater than three times more effective than traditional firefighting agent delivery systems and allows for smaller trucks to be built with equivalent capability.

Materials and Manufacturing Directorate scientists then began work to modify a P-19 that would be as effective as the standard vehicle. The platform was designed to incorporate three different agent application technologies: UHP water technology; compressed air foam; and dry chemical agent.

The major characteristics of the UHP P-19 involve a bumper turret capable of supporting both UHP and combined agent nozzles, along with separate UHP and combined agent hand lines. The roof turret has been removed because qualitative fire testing as well as quantitative flow characterization, has shown that the 300 gallons per minute UHP bumper turret has firefighting effectiveness equivalent to that of the standard 500 gallon roof turret. Feedback from operators has shown it to be more ergonomically correct for the firefighter because they can see both the agent stream as well as the target from one vantage point.

According to Carr, the UHP P-19 at Tyndall was the result of much computational technology and experiments that eventually resulted in downsizing a standard truck. The water carrying capability was reduced from 1000 gallons to 730 gallons without losing any firefighting effectiveness. This 730-gallon water carrying capacity is roughly equivalent to the 750-gallon future fire trucks that will be bought using UHP agent delivery systems. These new trucks will be at least twice as effective as the current P-19, resulting in the equivalent of three 1000-gallon existing fire trucks on the ground. In short, the fire research laboratory has demonstrated the capability to build smaller yet equivalent trucks using upscaled UHP water.

"Since the UHP P-19 has been brought to full operational capacity, the test bed has shown significantly increased firefighting effectiveness over the standard P-19 even though it discharges only 60 percent as much firefighting agent," said Carr.

With these promising results and endorsement of nearly all Air Force major commands, a need was presented to create guidelines for ARFF vehicles of the future. AFRL has collaborated with the Air Force Civil Engineering Support Agency to determine specifications for the next generation ARFF vehicle based primarily upon the current capabilities of the UHP P-19 demonstrator.