NTSB's latest set of recommendations asks FAA to head back to the drawing board on the fiscal feasibility of requiring fire suppression systems on freighters.
The recommendations, issued just two weeks after the board added fire safety improvement to its most-wanted list, include a call for "active" fire suppression systems in cargo compartments, containers, or both. The point: install something that suppresses fires so crews aren't forced to take evasive action often with just minutes to spare, and sometimes without enough time at all. Another recommendation calls for enhanced fire detection system performance requirements, while a third focuses on improved cargo container flammability standards.
The board's fire safety push isn't new. A series of recommendations in 2007 (.pdf) focused on similar areas, with one calling specifically for fire suppression systems. FAA responded with a study that said such systems were too costly for the calclulated benefit. The study, "A Cost-Benefit Analysis for the Installation of Fire Suppression Systems in Cargo Compartments of Cargo Airplanes," (.pdf) found just four accidents in the four decades spanning 1967-2007 that met FAA's criteria for being an accident worth preventing. (While no accident is desirable, for the purposes of calculating cost/benefit, the agency sought to eliminate accidents that caused death, serious injury, or significant aircraft damage.). One of these was the February 2006 UPS DC-8 accident at Philadelphia (.pdf) that led to the 2007 recommendations, including NTSB's call for fire suppression systems.
The bottom line from FAA's report:
It is concluded that Halon fire suppression systems, or alternatives that are likely to be developed for below floor cargo compartments, are unlikely to be cost beneficial for the cargo compartments of cargo aircraft. Fire suppression systems, of the kind currently being considered for the cargo compartments of combi aircraft, may prove to be cost beneficial, particularly on larger cargo aircraft.
What's changed in three years? For starters, as NTSB notes, there have been two more major, fired-related freighter accidents, including one involving an N-registered aircraft: UPS 6, which crashed near Dubai International Airport on September 3, 2010, killing both crew members and destroying the aircraft. Also, the board itself also has concluded, based on tests, that current regulations allow fires to develop far too much within cargo containers before they're detected by flight crews or onboard fire detection or suppression systems.
Read NTSB's full recommendation letter here (.pdf).