The crash of a commercial jetliner raises the specter of such overwhelming death and destruction that most people would rather not consider the possibility. Unless a community is in close proximity to an airport, it is often difficult to get the commitment of resources to plan for such an event. However, it is the responsibility of emergency managers to plan for the unthinkable. For those individuals who insist that these types of incidents only occur "someplace else," remember that to emergency managers in other municipalities, your community is somewhere else.
In this series of articles, we will consider the role of fire, law enforcement and EMS agencies when responding to an off-airport aircraft crash. In this issue, we begin by reviewing aircraft rescue firefighting.
In order to certify them as airworthy, manufacturers of commercial jetliners must demonstrate that their aircrafts can be evacuated of their full capacity in under three minutes, utilizing only half the available exits.1,2 However, a jet aircraft can still be compared to a crowded movie theater with too few exits to pass any building code in the country.
Due to the nature of the combustibles involved in an aircraft crash, the physical forces which are experienced and the potentially large number of victims, strategic priorities differ from other types of firefighting scenarios. In ARFF, the emphasis is more heavily weighted toward rescue than in structural firefighting. With a potential 300+ victims, many of whom will have suffered burns and/or traumatic injuries and are in need of extrication, all available resources must concentrate on the rescue effort. This often involves the tactical decision to ignore a large body of fire until after rescue of the passengers and crew is accomplished.
The rule of thumb is initially to fight only the fire that interferes with the rescue. Once the rescue is completed, resources can then be redirected to firefighting. This is in contrast to a structural fire response, where saving the bedrooms from a kitchen fire is considered a win. After all, you can't save half an airplane!
Aviation fuels burn at extremely high temperatures, between 3,000°F-4,000°F. The environment inside an aircraft cabin can reach uninhabitable temperatures within two minutes. By employing the "area concept" technique of blanketing the outside of the fuselage with overlapping streams of firefighting product to draw off heat, escape time for passengers can increase significantly.
Tests conducted at the Federal Aviation Administration's (FAA) research facility at Atlantic City Airport in New Jersey demonstrate that a fuel fire inside an aircraft cabin can reach temperatures that lead to flash-over conditions in less than four minutes. The immediate application of massive quantities of cooling firefighting product to draw off this heat is the most effective technique for increasing survivability in a low-impact aircraft crash fire incident.
When planning a fire attack, certain basic principles should be employed. The responding firefighting force should make the initial attack from upwind of the fire. This allows nature to reduce the amount of heat and smoke these firefighters will encounter. Remember that structural firefighting protective clothing provides inadequate protection against extreme temperatures generated by burning aviation fuels. When approaching the scene, firefighters should realize that due to their limited initial firefighting capacity, they should not waste time or product extinguishing fires that do not involve passenger areas. Burning wings, engines and landing gear do not normally contain passengers, and unless the fire is encroaching on passenger or other inhabited areas, it should be ignored until passenger rescue is complete.
The first priority is to create and maintain a rescue/escape path for passengers evacuating the aircraft. Secondly, product should be applied to cool the areas of fuselage where radiant heat from a fire has begun to encroach. Finally, after the passengers' safety is established, and if sufficient quantities of firefighting product are available, mop up of other areas can begin.
The FAA has promulgated Federal Aviation Regulations (FARs) on a variety of subjects involving operations of aircraft and airports. FAR Part 139 [14CFR Part 139] deals with, among other things, aircraft rescue and firefighting. Part 139 details the required areas of training for aircraft rescue firefighters, and specifies the type and capacity of equipment available to respond to such incidents.
Aircraft rescue firefighting vehicles can be categorized into four types: rapid intervention vehicles (RIV); large capacity foam vehicles; tankers; and miscellaneous ancillary vehicles.
Rapid intervention vehicles quickly deliver a sufficient quantity of firefighting product to extinguish a small aircraft fuel fire or knock down a large fuel fire. Personnel on this equipment will also make the first evaluation of the incident and begin rescue operations. These vehicles carry 100-1,000 gallons of water and aqueous film-forming foam (AFFF), as well as a secondary extinguishing agent (Halon, carbon dioxide or dry chemical powder). To meet FAA mandated standards, this vehicle must be able to reach the midpoint of the furthest runway from the fire station and begin firefighting operations in three minutes or less from the initial alarm.
Large capacity foam vehicles carry up to 6,000 gallons of water and AFFF. They discharge firefighting foam through turrets at up to 1,200 gallons per minute or more, as well as through hand lines and under truck nozzles. They must be able to arrive at a scene within four minutes after an alarm is sounded.
Tanker vehicles may be utilized to transport large quantities of water or foam concentrate to the scene for replenishment of ARFF vehicles.
Other vehicles in an ARFF fleet may include command and communications vehicles, stair trucks, ambulances, MCI equipment carriers, hazardous materials/decontamination units, ladder and hose trucks.
The FAA makes yearly surprise tests of response time, equipment and training records. Failure to meet mandated standards can result in hefty fines and/or loss of certification.
The first chemical foams were developed in England in the late 1870s. The United States Army Air Corps began using chemical foams formed by reactions of such materials as aluminum sulfate or sodium bicarbonate and water, in combination with foam-stabilizing agents, in the 1930s. In 1935, the Army switched to mechanical foams where a liquid foaming agent is mixed with water and air. Examples of these mechanical foams include protein foams, which are albumin based, and fluoroprotein foams, in which glycols were added to stabilize the foam.
In the 1960s, the United States Navy, along with 3M, developed Aqueous Film Forming Foam (AFFF). AFFF is totally synthetic and contains fluorocarbon surfactants which cause a thin aqueous film to drain from the foam bubbles and float on top of the liquid hydrocarbons. This traps the vapors and results in fire extinguishment by removing the fuel source. In addition, the cooling action of the bubbles removes the heat, resulting in faster extinguishment.
Firefighting foams are generally available in 1%, 3% and 6% concentrates. The percentage refers to the number of gallons of concentrate to be mixed with water to produce 100 gallons of firefighting product. For example, one gallon of 1% AFFF concentrate is mixed with 99 gallons of water, three gallons of 3% concentrate is mixed with 97 gallons of water, or six gallons of 6% concentrate is mixed with 94 gallons of water to make 100 gallons of product. What comes out of the nozzle or turret is exactly the same. Since mobile proportioning systems cannot be accurately calibrated at the 1% level, these concentrates are utilized only in fixed-base operations such as refineries and fuel storage facilities and are not used for ARFF.
One of the simplest and least expensive methods is calculation of the booster tank foam recipe for your equipment. This involves taking the capacity of the on-board water tank on the fire truck, calculating the amount of foam concentrate needed, and then storing it on the truck ready for use. For example, a 500-gallon booster tank would require 15 gallons or three 5-gallon buckets of 3% AFFF concentrate. Placed in the hose bed near the tank fill, the foam concentrate could be dumped into the tank before the apparatus departs. The drive to the scene would sufficiently mix the water and concentrate to produce 500 gallons of pre-mix. With a standard water fog nozzle, this would produce the firefighting equivalent of 1,500-3,000 gallons of firefighting product. If an air aspirating nozzle was utilized, then the coverage would approximate 1,500-7,500 gallons.3 Firefighters should be familiar with, and have available, foam eductors and a supply of foam concentrate at the scene to continue firefighting efforts.
Although it is possible, but not desirable, to apply protein foams along with AFFF on the same fire, water should never be applied to a foam blanket as it will dilute and wash away the protection. It is also important not to mix different types of foam concentrates together. To insure the safety of rescuers and to prevent possible reignition of fuel vapors, when the foam blanket has dissipated, it should be replenished. A visible and complete foam blanket is necessary to insure vapor suppression.
In a low-impact crash, the pilot is able to make a fairly controlled landing and the fuselage remains relatively intact. There may be an associated fuel fire. Responders will treat a large number of survivors suffering from force injuries and burns. The local EMS system will be overloaded. A wide body jet may carry up to 400 passengers, and appropriate hospital beds will have to be located.
In a high-impact crash, the forces involved are much greater and there will be few, if any, survivors. The stress on responders increases as it becomes apparent that few lives can be saved. The clean-up operation, body recovery and identification process will tax the local medical examiner or coroner's staff.
If the aircraft breaks up in mid-air due to an explosion or collision, aircraft wreckage and bodies may be spread over a wide area. If the aircraft lands in water, reaching the fuselage, rescuing survivors and combating a fire will be difficult. In these cases, even a shallow water crash will have severe environmental consequences.
Response planning should include designation of primary and back-up locations for triage and treatment of victims. Suddenly you are faced with 325 victims with injuries ranging from minor abrasions to fractures, burns and major trauma. Where will you treat them? How many hospital beds are available? How will you transport patients?
Devise a plan and conduct a tabletop exercise to test it. Include neighboring fire, EMS and law enforcement agencies in your exercise. Disaster drills and exercises are the time to work out mutual aid bugs. Also, contact the local funeral home association to assist in planning for a multiple fatalities incident. Contact state and federal agencies for potential sources of assistance, from FAA Planning Guides to DMAT Teams.
In any event, responders to an aircraft crash will have to take special precautions to protect themselves. Beyond the obvious danger of fire, unburned jet fuel is a carcinogen that can be absorbed through the skin; prolonged inhalation of vapors can lead to development of chemical pneumonia; and some equipment can be permanently contaminated if it comes into contact with fuel.
Aircraft fuselage may produce sharp edges that can easily tear through bunker gear. Aircraft landing gears are made of materials that will burn at extreme temperatures and react violently if extinguishment with water or foam is attempted. Aircraft engines may continue to operate for some minutes after a crash, even if they have become dislodged. In an emergency landing or low impact crash, jet turbines may produce sufficient thrust to overturn responding apparatus and suck in loose equipment or even personnel who get too close. A bump against a propeller can restart a reciprocating engine if it has not been properly shut down. Pressurized lines and containers may contain fluids or gases at extremely high pressures. Some of the fluids may be flammable or toxic. In older aircraft, oxygen may be distributed from central tanks through pressurized lines. Surface control cables can be under extreme tension, and if cut, may react with enough released energy to cause serious injury or death. Electrical lines may remain energized.
The new composite skin of modern aircraft is made up of materials that when cut by a power saw can release dangerous dust and micro fibers. Responders must also take care to avoid the biohazard dangers presented by body parts and fluids, and to avoid unnecessary contamination of equipment by carefully choosing equipment staging sites. A decontamination station for personnel and equipment should be established, and a perimeter established to prevent cross contamination.
During and following ARFF operations, it is important to remember that a plane crash is a crime scene until proven otherwise. A number of local, state and federal law enforcement agencies will be involved in the investigation into the cause of the crash. Responders should take care not to unnecessarily disturb aircraft parts. If it is necessary to move something in order to accomplish rescue or fire extinguishment, then try to remember the original location or orientation of the part and convey that information to investigators. Above all--no souvenir hunting! A perimeter should be quickly established and only those persons actively involved in the operation should be permitted access. Preventing unauthorized access is infinitely easier than clearing the area of bystanders later.
Before recovery of bodies or body parts commences, photographs should be taken to document their location in relation to the aircraft and surrounding area. This documentation may assist in identification of parts and research into what steps can be taken to improve crash survivability in the future.
All involved personnel should be strongly encouraged, if not mandated, to participate in Post Incident Stress Debriefing. This type of incident exposes responders to a situation outside of normal human experience and long-term mental health dangers cannot be overlooked. Recovery of the community should also be encouraged. As soon as possible following the event and investigation, clean-up of the area and restoration to pre-crash conditions should be accomplished. Residents should be offered counseling and be involved in the restoration in order to restore a sense of control.
An airplane crash is not simply a big automobile accident. The combination of a massive, three-dimensional liquid hydrocarbon fire, a widespread trauma and burn MCI, and a high-profile media event makes this an extremely difficult situation to prepare for. However, the careful planning and training you will do in order to deal effectively with this type of event will also improve your response to other types of emergencies.
| Kenneth D. Honig, CEM, EMT-P, is the senior course coordinator for Critical Incident Management and Training Associates (CIMAT) in North Bellmore, NY. CIMAT provides training and emergency management consulting services. Kenneth is a certified emergency manager with more than 20 years of experience in EMS, law enforcement and firefighting. He has spent the past 13 years as a police officer, patrol supervisor and aircraft rescue firefighter. He's also an editorial advisory board member for EMS Rescue Technology. |