Weight and Balance Behavior of a Freighter Aircraft During Cargo Fire Test Evaluations
The Federal Aviation Administration Airport Technology Research & Development Branch conducted a Full-Scale Cargo Fire Research Project that involved a series of firefighting-related tests with an Airbus A310 cargo aircraft. One test included a study of the weight and balance characteristics of the aircraft during a fire attack. Aircraft are sensitive to loading configurations; therefore, personnel working on and around the aircraft must ensure the aircraft remains within aircraft manufacturer’s recommended weight and balance guidelines during loading and unloading. Aircraft Rescue and Firefighting (ARFF) personnel must be equally aware of these weight and balance guidelines when responding to an aircraft accident or incident. Depending on the severity, impacts or abrupt movements affecting the aircraft during the event can cause a shift in load, which would adversely affect the weight and balance. Freighter aircraft are particularly susceptible to weight and balance issues due to cargo weight and varying locations on the aircraft in which the cargo can be placed.
The research effort focused on many factors involving aircraft stabilization and identified the issues ARFF should consider to prevent an aircraft tail tip from occurring. Researchers documented changes in the aircraft height at four locations around the aircraft to see how the introduction of water and agent affected aircraft balance during full-scale fire tests to determine the weight and balance behavior of the aircraft. However, throughout the numerous fire test scenarios that were conducted, researchers were unable to identify any significant changes in the aircraft’s height. When the tests were complete, researchers purposely attempted to create the conditions necessary to tail-tip the aircraft. Researchers successfully achieved a tail tip after adding roughly 6200 gallons of water to the aircraft and concentrating the weight of the water to the aft of the aircraft, thereby causing a tail-heavy condition.
A review of aircraft weight and balance industry practices identified several pieces of equipment that could aid ARFF personnel in maintaining aircraft stability during emergency responses. This report identifies factors of aircraft stabilization for aircraft rescue and firefighting personnel as well as equipment that could aid firefighting personnel in maintaining aircraft stability during emergency responses.
DOT/FAA/TC-TN13/51
Author: Jack Kreckie and Jonathan Torres