Fire Safety and Technology Editorial
Aircraft Fires
From a statistical point of view, flying in commercial
airlines in the US is extremely safe. Roughly speaking, 5 billion people
have flown on US commercial flights since 2002; during that time there
have just been three fatal crashes.
Unfortunately, all three crashes involved commuter airliners:
21 people died in Charlotte, North Carolina, on January 8, 2003 (Beech
1900D turboprop); 49 passengers died in Lexington, Kentucky, on August
29, 2006 (Bombardier Canadair Regional Jet 100ER); and 50 people (including
one on the ground) perished in Buffalo, New York, on February 12, earlier
this month (Bombardier Dash 8 Q400 turboprop; see Fire Incident Reports).
The circumstances and the type of aircraft were different
in each case, but there was one common fact: all three involved commuter
aircraft. Two of the crashes involved fires: the one in 2003 and the
one this month. These statistics are interesting because many business
travelers feel uncomfortable about flying commuter planes anyway.
Less than two weeks later, on February 25, there was another
aircraft crash, this time in Amsterdam, Netherlands. This accident did
not involve either a fire or a commuter aircraft; however nine people
(including the pilots) perished, in a Boeing 737 used by Turkish Airlines
and bound for Amsterdam, with 134 people on board.
The excellent fire record of aircraft has often been highlighted
in FS&TB; it is important, therefore, to discuss a case where fire
fatalities occurred. In the Buffalo incident it appears that the fire
resulted from the collision between the aircraft and a home on the ground,
after the pilot, or pilots, lost control.
Fire safety requirements for aircraft are intended to
address two key survivable scenarios: (1) a fire during flight, to be
kept small enough for the aircraft to land safely and evacuate and (2)
a fuel fire following a crash landing, where some time needs to be available
for passengers and crew to escape.
It appears that, in this incident, there was no in-flight
fire. Scenario (1) does not apply.
The question is, then, if this is similar to a scenario
(2) fire, whether the aircraft interior materials should have delayed
the fire growth enough to allow passengers and crew to escape. It appears
that the aircraft crashed belly-first onto the house, which suggests
that at least some passengers would have been injured in the crash.
Moreover, the crash appears to have broken a natural gas line in the
house. Once the aircraft crashes and breaks (into three sections), the
liquid fuel will easily catch fire and the fire will grow by flames
feeding not only on the aircraft interior materials but also on the
gas in the house and on the house's furnishings and contents.
The house on which the plane crashed was likely to have
furnishings and contents that represented both a significant fuel load
and which exhibited normal residential (i.e. poor) fire performance.
In fact, firefighter rescue teams were still battling a raging fire
the next day, hours after the crash.
Thus, even with the excellent fire performance of the
aircraft interior materials, the combination of natural gas, household
products and aircraft fuel suggest that this fire occurred too fast
for the airplane occupants to have an adequate chance to escape, irrespective
of the fire performance of the aircraft interior materials.
Let's go back to commuter airlines. It is interesting
that many commuter airline flights are actually operated by the same
airline: Colgan Air operates as Continental Connection, United Express
and US Airways Express, offering daily scheduled service to 53 cities
in 15 states & Canada.
The Buffalo accident involved a Colgan Air service. This
airline also runs commuter flights under the Northwest Airlink and Delta
Connection names for the merged Delta Air Lines/Northwest Airlines.
This particular airline is not unique and the arrangements are the result
of agreements between the larger airlines and these commuter airlines
in order to save in pilot salaries (which are based, in part, on the
size of the aircraft).
The typical commuter airline aircraft are 37 and 50 seat
regional jets and not turboprops. They have smaller fuselages and make
travelers feel crowded and uncomfortable, especially because they have
"weight and balance" issues, which often force travelers to
change seats to help the pilot balance the aircraft.
Some commuter airplanes (and private aircraft) are only
required to meet less severe fire safety specifications than large passenger
airplanes, if they are propeller-driven, have a seating configuration,
excluding pilot seats, of 19 or less, and a maximum certificated takeoff
weight of 19,000 pounds or less. Such commuter aircraft are relatively
rare. From the point of view of fire safety, most commuter airplanes,
including the one that crashed in Buffalo, must meet the same FAA requirements
as do larger aircraft. Thus, we should trust them more than we do.
In summary, the Buffalo tragedy is not likely to be representative
of a lack of fire safety but simply of an agglomeration of problems
that rarely happen.
Marcelo M. Hirschler
