Double deck aircraft mockup enables firefighting research

  • Published
  • By Jennifer Kalberer
  • Materials and Materials Directorate
Responding to operational challenges posed by the new generation of large double deck aircraft, Air Force Research Laboratory engineers here have developed a mockup to research how to best fight fires and save lives in the event of a crash.

The AFRL Materials and Manufacturing Directorate Airbase Technologies Division at Tyndall, working in collaboration with the Federal Aviation Administration, completed the design, fabrication and installation of the 60-foot, full-scale mockup section of a double deck aircraft here.  

The new mockup will be used to conduct research and training related to aircraft rescue and fire fighting that cannot be accomplished with the mix of smaller-scale aircraft mockups currently available.

"In the early 1990s, AFRL created a one-third scale mockup of a C-130 cargo aircraft, which has been used extensively by both military and civilian agencies to complete thousands of fire evaluations over the past 15 years," said Virgil Carr, Fire Research Program Manager for AFRL's Materials and Manufacturing Directorate.

New large aircraft, such as the Airbus A380 and Boeing 747-8, present new challenges to current aircraft rescue and fire fighting (ARFF) principles, practices, theories, training and equipment. In turn, airport firefighters face greater risks as commercial aviation increases the number of passengers onboard, incorporates the use of composite materials and expands the fuel storage capabilities.

The Airbus A380, for example, almost spans the length of a football field wing to wing; can carry up to 873 passengers and crew; and can fly 8000 nautical miles--enough enough to fly non-stop from Chicago to Sydney--using 82,000 gallons of fuel.

In 2005, the FAA requested AFRL design and build a double-deck aircraft mockup to act as the focal point for their fire research programs, Carr said.

"The result is a new large aircraft mockup that is constructed of ¼ inch plate steel, erected on 12-inch diameter support legs," he said.

The fuselage section of the new mockup measures over 27 feet in diameter and is reinforced with gussets to keep the oval design from warping because of the intense heat generated from the hydrocarbon fuel fires. The fuselage encompasses the cargo, main and upper passenger decks plus the first three passenger doors directly behind the cockpit. Each 10-foot section is joined with a specially designed spacer that allows the steel to flex in the horizontal direction, minimizing deformation. 

The wing is designed to represent the first 10 feet of the leading edge and possesses three-dimensional characteristics for realistic fire fighting. A 20-foot section of the inner engine nacelle is suspended from the wing.

Carr explained plans are already in the works to design an interior engine capable of simulating spray fuel fires typical of those encountered in a real aircraft. A set of three plate steel, high temperature evacuation slides has been fabricated and can be used on either the wet side (for live fire evaluations) or on the dry side (for vehicle and other non-fire evaluations). The entire mockup is instrumented with over 75 thermocouples to monitor the thermal loading of the mockup, as well as, provide critical data on temperature and fire behavior.

In the spring of 2007, the new large aircraft mockup was dedicated into service by military and civilian dignitaries, signifying the start of a new era of ARFF research. Over 40 guests from the FAA, Air Force, aircraft industry and international ARFF community attended the one-day event that included a tour the mockup and demonstrations of new fire fighting equipment.

Currently, the FAA has plans to evaluate a 65-foot high reach extendable turret for upper deck fire fighting and to investigate the complexities of composites in aircraft fires; and test interior intervention vehicles for firefighter entry and passenger egress during emergencies.