THE INS AND OUTS OF AIRCRAFT PASSENGER RESCUE
It was a crystal clear evening when the Boeing 737-300 was cleared for landing at a large western international airport. The captain requested over the intercom that the flight attendants prepare the cabin for landing. The sleek twin-engine jet turned gently from the base leg to the final approach, and the engines were throttled back for the descent. It had been a smooth, uneventful flight and the mood inside the near-capacity cabin was calm and quiet. The flight attendants had finished with last-minute cabin-landing details and were seated in their assigned positions. The aircraft was aligned with the center stripe of the designated runway, and the glide slope and approach were textbook perfect. The tower gave the captain final landing clearance, and the captain made the last cockpit checks for gear extension, flap, and engine power settings. The aircraft was over the threshold, and the main landing gear was seconds away from reaching out to touch the runway surface. Touchdown, and a peculiar feeling and noise level were apparent-something was wrong! The aircraft then made an abrupt turn to the right and came to a jarring stop within seconds. The passengers and crew immediately noticed the intense orange glow through the cabin windows, and the acrid smell of burning jet fuel permeated the cabin. Above the screams of the scared and injured overwhelmed occupants and in the thick, choking black smoke, someone was yelling, “Unfasten your seat belts and come this way.”
AIRCRAFT PASSENGER RESCUE
But where was “this way”? And how could the passengers get there? What direction was the voice coming from?
Passengers anxious to get out of a burning aircraft wrestle with these questions, and some of them control their panic by thinking, Surely rescue and firefighting crews are responding and they will guide us to safety.
Some of the people were just sitting there —alive and uninjured but not moving. Others appeared to have lost all sense of direction and were immobile and crowded together. The sound and feel of spraying water suddenly caught the attention of those in the cabin area. Rescue was at hand. Or was it? Their chances for rescue depended on the responders’ knowledge of how the aircraft’s doors and emergency-escape systems operate— on whether the would-be rescuers would be able to gain access to them.
With this scenario in mind, let’s examine, identify, and review some key points involving emergency aircraft entry and rescue.
The suddencss of this accident and the resulting fire prompted the methodically trained flight crew to go into action. They issued the command, “Unfasten your seat belts and come this way.” Not all occupants heard, understood, or followed these directions. The occupants were confused. shocked, and in a state of negative panic, resulting from their belief that they would perish. They just sat there frozen in their seats. Other passengers responded to the ominous threat by aggressively attempting to escape from the burning aircraft —a classic example of positive panic, resulting from the overwhelming will to survive. These and other behavioral patterns are common in aircraft accidents and should be recognized.
Passenger gridlock in the aisles often is a problem. The contributing factors to the gridlock are many: inability to find the exits and the compulsive need of some passengers to exit from the door—Door 1 Left — with which they are most familiar, despite urgings by flight crew members to use other exits. Door 1 Left quickly becomes blocked by panicked, injured, and disabled passengers and therefore is impassable in an emergency. Rescuers, therefore, must he extremely cautious when considering Door 1 Left as the primary exit for evacuation and rescue.
Often exits become congested when passengers attempt to exit the nearest over-the-wing doors all at one time and become stuck in the exit way, which is designed to accommodate only one person at a time. Seats, aircraft interior components, overhead luggage, and personal effects of passengers contribute to the congestion, as do dislodged galleys and beverage carts. Escape is further impeded by the aircraft structure twisting, rolling, and fracturing. In addition, our research indicates that SO percent of commercial aircraft exits become unusable in a crash situation, a statistic that sets the scene for an extremelycomplicated rescue problem.
How is all this relevant to you? Pause for a few minutes and visualize an aircraft accident scene like the onedescribed above. ‘ITten, answer the following question: How familiar are you with the doors and egress systems on the aircraft that you or your department may be called to during an emergency?
A basic working knowledge of this area can help you save many lives and perhaps millions of dollars in property in the event of an aircraft incident. Following is an overview of the types of doors and escape systems currently found in aircraft and characteristics of aircraft emergencies.
AIRCRAFT EXITS AND ESCAPE SYSTEMS
All aircraft have entrance and exit doors. They are engineered to facilitate evacuation of occupants under normal and emergency conditions. Each model and category of aircraft in service has a door system designed for its specific application. Our research has shown that each aircraft model — with few exceptions—has a different type of exit door, with operating procedures ranging from simple to complex. In addition, the aircraft manufacturer will tailor an aircraft to meet the customer’s specifications, sometimes making the aircraft unique with respect to other existing models of the same aircraft.
The Federal Aviation Administration (FAA) requires that aircraft designated for carrying passengers be equipped with a sufficient number of exits, hatches, and evacuation slides (which statistics show have a 20 percent failure rate) to accomplish evacuation within three minutes using one-half of the aircraft’s exits. These requirements are unrealistic and were derived from tests conducted under laboratory conditions with trained, briefed victims—without the realities of panic, smoke, fire, poor visibility, and obstructed escape areas.
The complexity of the escape systems varies. Doors and escape systems are not standardized throughout the aircraft industry. The lack of industry standards coupled with limited emergency responder knowledge or exposure can intimidate and challengerescuers who must enter and exit the aircraft safely for evacuation or rescue.
GENERAL AVIATION AIRCRAFT
The three most common general aviation aircraft firefighters will encounter are Cessna, Piper, and Beechcraft. Although these aircraft sharesimilarities related to the engine system, construction, and passenger, fuel, and baggage capacities, the egress systems vanaccording to the manufacturer.
Aircraft egress doors are similar in complexity to those of automobiles and other vehicles.
While the opening and locking devices on aircraft doors usually are easy to operate under normal situations, they can present a demanding forcible entry problem under emergency conditions.
AIRCRAFT PASSENGER RESCUE
Following are some basic characteristics of the three aircraft mentioned above.
Cessna aircraft, high-wing types, have the same basic door configuration on each side of the fuselage (the body or cabin area). These doors latch and lock on the aft (rear) portion of the door and are easy to force, even when locked. The doors incorporate a swing latch window that is equally simple to open.
In contrast, Piper and Beechcraft are low-wing aircraft and have egress doors—with single or multiple latching devices—built into one side (usually the right side) of the fuselage. Doors in these aircraft swing forward and are of lightweight construction. As should be the case with any aircraft, try the door before prying.
BUSINESS CORPORATE AIRCRAFT
Ibis aircraft category holds a unique niche within the aviation environment. The corporate fleet consists of general aviation, commuter, and high-altitude, high-performance corporate turbo prop and jet-propelled, commercial-class aircraft. Some examples of these aircraft are the Beechcraft King Air 200, Cessna Citation I. bear Jet AO, Saberliner BO, Canadair Challenge 600, BAH US 125-700, Falcon 50, and the Gulfstream Aerospace series Tile exit doors on these aircraft also are nongeneric and open in all directions. They have a wide assortment of handles and latches and builtin airstairs. These aircraft along with commuter-type aircraft have a plugtype pressurized cabin door—the door is built larger than the opening as a sealing mechanism for pressurizing the aircraft.
COMMERCIAL COMMUTER AIRCRAFT
Commuter aircraft incorporate the broadest spectrum of aircraft. They include twin-engine internal combustion reciprocating and radial engines and a variety of turbo prop and jet aircraft. Some examples are the Doriner 228; De Havilland DHC-6-7-8; Embraer 11 OP, Bandeirante, EMB 120, and Brasilia; Swearingen Merlin IV or Metro II; Shorts 360; and the BAE 146 four-engine jet, which also serves in the commercial narrowbody class. The increasing demand for this category of aircraft and the number of manufacturers producing this product make it difficult to maintain familiarization with this line of aircraft. Use of these aircraft also tends to be regional, limiting national exposure.
Most commuter aircraft can carry from 12 to 90 passengers and have a wide variety of exit doors and opening mechanisms. Some commuter doors open forward, aft, free-fall down, and have steps built into the door, while others are a split clamshell-tvpe configuration. Because the bulk of these aircraft are designed to operate at high altitudes and are built to withstand various pressure and temperature changes, the airframe must be durable. Pressurized plugtype cabin doors are standard features on these aircraft. With few exceptions, most plug-type doors open and swing forward. Most commuter aircraft are not equipped with evacuation slides, and cabin evacuation is accomplished by stairs constructed into the aircraft’s doors or by ground equipment. These aircraft usually rest low to the ground with the landing gear extended, and it is not difficult to evacuate passengers. Commuter aircraft also have over-the-wing, or window, exits. These exits, designed for ease of operation, provide a simple, quick, efficient means of entry into the cabin. Over-the-wing exits on commuter aircraft are quite small and usually will not accommodate rescue personnel in breathing apparatus. Over-the-wing exits also provide an excellent means of employing handlines for direct or indirect cabin firefighting.
NARROW-BODY COMMERCIAL JET AIRCRAFT
The Boeing 727-(100, 200), 737(100, 200, 300,400), 757; McDonnell Douglas DC-8, DC-9, MD-80 models; the British Aerospace BAe 146; and the Foker FI00 series make up the majority of the aircraft in this category. The exit doors on these aircraft are plug-type doors and are identical on both sides of the fuselage. They are normal entry and exit doors and operate in the same manner. Most airlines identify these doors by painting a contrasting white border around the exterior door frames. These doors are given numerical and alphabetical designations that are used universally. For example, Door One Left, the first door on the left forward side of the fuselage is designated as “one left” or 1L; all other doors on the left side then follow in sequence—2L, 3L. The doors on the right side of the aircraft are numbered 1R, 2R. 3R, beginning at the nose and continuing aft. The Boeing 727-100 has only two cabin doors, IE and 2R. The 737-200 series has four cabin doors (1L, 2L, 1R, 2R). The McDonnell Douglas DC-9 also has two cabin doors (1L and 2L), and the MD80 series has three cabin exit doors (11.. 2L, and 1R). The number of doors on the Boeing 757 is identical on each side of the fuselage and ranges from six to eight, depending on tlie model. Over-the-wing or window exits are not included in the door-numbering sequence.
AIRCRAFT PASSENGER RESCUE
The doors on the left or port side of the aircraft are designated as normalentry doors, while those on the right or starboard side of the aircraft are called service doors. Plug-type doors are simple to operate and use various types of opening devices. Some common exterior door-opening devices are single handles that are pulled out of a stowed position and rotated forward (toward the nose of the aircraft). Other aircraft have offset bars and butterfly-type door handles, which also are pulled from a stowed position, engaging a clutch mechanism. and then are rotated aft (toward the tail of the aircraft). Instructions for operating the door and handlerotation arrows are placarded on the doors in close proximity to the opening mechanism. When possible, always read and follow these instructions prior to opening.
Interior door controls usually are a single bar-type handle with a rotational arrow illustrating the direction of rotation painted on the door. Important key points to remember are that exterior and interior door handles on Boeing narrow-body aircraft rotate aft. In contrast, McDonnell Douglas narrow-body aircraft exterior and interior door handles rotate forward. In poor visibility, darkness, or a smokefilled cabin or when door instructions have been burned away, not understanding or visualizing the correct exterior and interior handle rotation could have serious consequences with respect to an evacuation or rescue effort. These doors normally open and swing forward and lock into the side of the fuselage on contact by means of a “gust” or “hold-open” lock. Each of these aircraft has a different type of gust lock. If it becomes necessary to close these doors, the gust lock first must be deactivated or the door will not close.
The McDonnell Douglas DC-8 series aircraft (both standard and stretch models) have up to 12 exits. This aircraft has plug-type doors and jet escapes (Class I-type doors) as well as over-the-wing (window) exits. Jet escape doors are located one forward and one aft of the wing on each side of the fuselage. These doors are hinged at the bottom and weigh approximately 375 pounds. When activated, they free-fall, swinging down to within four feet of the ground—with the aircraft on its landing gear —and deploy an evacuation slide. This is an extremely dangerous door and all safety precautions must be followed when operating jet escapes.
All narrow-body aircraft doors are equipped with an emergency slide designed to inflate automatically or manually when the door is opened in an emergency situation. These doors are required to be armed (prepared for emergency operation) by flight attendants prior to takeoff. Some airlines place a red or yellow band across the door’s viewing window, which indicates the door is armed. The door remains armed until the aircraft has safely landed and is parked at an airport gate. A simple procedure is used to arm the door. A girth bar is manually removed from its stowed position on the slide pack and fastened to the floor of the aircraft. When the door is opened the evacuation slide, which is stowed in a container attached to the door, is pulled from the container and charged with 1,800 psi of compressed air from a cylinder within the slide container. Each evacuation slide has a backup system to manually inflate the slide. A red or yellow manual inflation handle is attached to the top of the slide at a right, center, or left location. When pulled, it manually inflates the slide in the event of a system malfunction.
AIRCRAFT PASSENGER RESCUE
Evacuation slides also serve as flotation devices in the event of a water landing. As previously mentioned, rescue personnel should consider that the evacuation slide may fail, since 20 percent do.
With the exception of the Boeing 757, narrow-body aircraft doors are incapable of being disarmed from the exterior of the aircraft and always must be treated with caution. Always assume that a plug-type door is armed and that an evacuation slide will deploy. The slide inflates with considerable force, usually within five to seven seconds.
To open armed doors safely, responders must position ladders aft of the doors and high enough to have effective support on the ladder rungs, operate the opening mechanisms, forcibly push the door forward, and quickly move aft to the safety of the ladder to avoid the dangerous slide deployment area.
Over-the-wing or window exits are required on narrow-body aircraft. Usually, there are one or two exits on each side of the fuselage. These exits are extremely easy to operate and contain no evacuation slides.
A late entry into the narrow-bodv class, the Boeing 757 is fitted with evacuation slides for over-the-wing exits and features two window exits on each side of the fuselage. The window exit evacuation slide is contained within a fairing aft of the exits where the wing flaps meet the fuselage. A manual slide inflation handle as well as an escape rope also are stowed in the frame of the window exits. The 757 incorporates the safety features found on wide-body aircraft. Evacuation slides and cabin doors on this aircraft can be disarmed from the exterior. The exterior door-opening mechanism on all eight cabin doors is the butterfly type used on the Boeing 747 series aircraft.
In place of an over-the-wing slide, narrow body aircraft (737. 727, DC-8, 707/727) have an escape lanyard stowed in the window exit door frame. The DC-9/MD80 series aircraft have this device stowed above the exit in the overhead luggage compartment. This escape lanyard is easy to remove and attach to a mooring point located on the upper portion of the wing. Deploying this lanyard provides an excellent means for maintaining stability to assist rescuers and escaping passengers down from a dry or wet wing surface.
Although these exits are easy to operate, they have limitations and drawbacks. The openings are small and will restrict firefighters in full protective gear and breathing apparatus. Also, they are heavy (approximately 75 pounds) and cumbersome, and care must be taken not to let the door fall onto a passenger, causing injury or blocking the exit. To operate these exits, activate the exterior latch and the release mechanism and rotate and remove the door. Place it on the wing clear of escaping passengers or thow it off the leading edge of the wing. Always issue safety warnings to those around or below prior to these operations. The trailing edge of the wing should always be laddered as an additional means of escape, especially when considering window exits for evacuation or rescue.
The McDonnell Douglas DC-9 and most MD80 series aircraft are equipped with forward airstairs found in a compartment below Door 1 Left and operated by electrical power. Unless rescuers are well trained in the complicated operation of these airstairs or an airline mechanic is at the scene, considerable time and effort may be lost with little results.
A few commercial aircraft have rear airstairs. All Boeing 727, most McDonnell Douglas DC-9, and all MD80 series aircraft have them. They operate under aircraft electrical power or a free-fall mode. Their controls are located in the interior and on the exterior of the aircraft. Rear airstairs. which appear to be an excellent means of egress, have some limitations. Extreme care must be taken when using these exits. Unlike other egress doors that open outward, the doors leading to the rear airstairs open in, and most passengers are not briefed on their operation. In an emergency evacuation, especially when the cabin is filled with smoke, passengers naturally try and push the doors out. They may continue to do this until they are overcome by smoke, fall unconscious, and block this exit. Then rescuers will attempt to open this door from the exterior against the downed victims.
AIRCRAFT PASSENGER RESCUE
Additional hazards associated with rear airstairs include the number of systems located in this area. Rearengine aircraft have multiple engines—-fed by four-inch-diameter fuel lines—located in this area. Extremely hazardous hydraulic accumulators with static pressures up to 3,000 psi also are mounted in this area. In any fire situation located in the aft portion of these aircraft, good judgment and caution must be used when considering rescue or firefighting operations. Also, this is not a viable area for forcible entry procedures, since it is heavily reinforced to support the vertical stabilizer and engine mounts.
Most of the McDonnell Douglas DC-9s and all MD-80 series aircraft have a tail cone that can be jettisoned (detached) and which automatically activates the deployment of a doubly wide evacuation slide. This operation can be accomplished from the aircraft’s interior or exterior. Exterior controls for this and the rear airstairs operation are located on the fuselage near the airstairs. Both exterior control panels are very accessible but were installed within close proximity of each other. Control functions and operating directions are labeled on each panel. Be sure to read the instructions to ensure activation of the correct control for the desired operation. The interior rear airstairs controls on the DC-9 and MD80 differ in that the DC-9 has one control panel while the MD80 has two panels—one for normal operations and one for emergencies.
Except for all models of the Boeing 747, there are no standard or generic cabin doors on wide-body aircraft. It’s quite common in fact to find different door configurations on the same aircraft. The McDonnell Douglas DC-10/ MD-11 aircraft and the Lockheed LI01 1 are prime examples. The DC10/MD11 models have eight cabin doors. The exterior controls of these doors are identical, while the interior controls are dissimilar. The front and rear door (doors 11. and 4R) interior controls are completely different from doors 21. and 3R. The 1.1011 has eight cabin doors, six of which are identical (11., 2L, and 31. and 1R. 2R. and 3R). However, doors 4L and 4R are different in that they’re smaller, always armed, and used only in emergencies.
A typical wide-body aircraft (McDonnell Douglas DC10/DC11), which shows main cabin doors and numbering and emergency evacuation slides deployed. This aircraft has no window exits.
The Boeing 767 and the A300 Airbus series aircraft have cabin doors and window exits. The A300 series has four cabin doors that are unique in that they pull away from the fuselage and slide forward, similar to doors on a van. All wide-body cabin doors have exterior controls that control normal and emergency functions designed specifically for that particular aircraft. A wide range of opening and closing exterior and interior mechanisms are common.
External opening devices consist of toggle switches, lift bars, “T” handles, push-in panels, and butterfly rotational handles. The interior door opening and closing devices on these aircraft are lift handles, emergency “T” pull handles, and slide arming and disarming levers, some of which are pinned for safety.
These doors rotate up into the top section of the aircraft fuselage during both normal and emergency operations. They open and close by electrical power under normal conditions and are propelled into an overhead position by 3,000 psi of compressed air or by spring tension when in the emergency mode. Using this mode of operation from the interior only automatically deploys the evacuation slide.
As previously mentioned, the Boeing 747 series aircraft have 10 identical cabin doors and operating controls. All exterior controls are butterflv-type handles; the interior controls are rotating handles similar to those found on narrow-body Boeing aircraft. All 747 cabin exit doors swing and latch forward and are relatively easy to operate.
The 767 and A300 series aircraft have window exits. These exits— unlike those in the narrow-body aircraft—are equipped with evacuation slides. When opened from the interior during an emergency, the evacuation slide deploys from a fuselage fairing at the trailing edge of the wing and will inflate and travel aft. Manual inflation devices also are installed in the window frames of these exits. What is most important to remember about wide-body cabin doors and window exits is that all wide-body doors and window exits can be disarmed from the exterior.
AIRCRAFT PASSENGER RESCUE
CARGO DOORS AND AIRCRAFT
All commercial aircraft have some type of cargo doors. Like exit doors, no two cargo doors are alike. Some basic rules do apply, however. Narrovv-hodv aircraft cargo doors operate manually, while wide-body cargo doors normally are power-operated and have a manual backup system.
Aircraft categorized as freighters also have crew evacuation doors and escape systems. Some of these aircraft were designed specifically for freight operations, while others have been converted from retired commercial aircraft. If converted, it’s common to find all cabin doors and window exits intact but nonserviceable due to interior modifications. Usually doors 1L and 1R are operational and serve as the primary crew exits. These doors and the escape systems are identical to their commercial counterparts.
Main cargo doors on freighter aircraft operate under hydraulic or electrical power. The lower cargo door usually is manually operated on narrow-body freighters and power-driven on wide-body cargo aircraft. In the absence of power, main and lower cargo doors can be opened manually with specialized tools available through the freight organization’s maintenance staff.
ADDITIONAL ESCAPE SYSTEMS
All commercial aircraft have a means of escape from the flight deck. One window on each side of the cockpit opens for escape. An escape rope or other lowering device is stowed and securely anchored above each cockpit window. To place it into service for descent, the rope is removed from its storage compartment and tossed out the opened window. This system—designed for crew escape-serves as an additional escape mechanism for firefighters and rescue personnel. Flight crews aboard the L1011 and 747 aircraft escape through a hatch over the flight deck that uses inertia escape reel-lowering devices.
Mandator)’ as of 1987, emergency directional floor track lighting is found aboard all commercial passenger-earning aircraft. These emergency lighting systems are installed on one side of each cabin aisle. When activated, white lights that terminate at exit locations guide passengers to the exits, identified by red lights. Illuminated exit signs also have been installed at floor level for better visibility in a dark or smoke-filled cabin. These additional emergency cabin evacuation aids are excellent tools rescue personnel can use when the need arises.
AIRCRAFT FAMILIARIZATION AND TRAINING
A good starting point for becoming familiar with aircraft doors and escape systems is to contact aircraft manufacturers and airlines for information. This information usually is in the form of aircraft manuals, diagrams, and wall charts that illustrate exits and their operations. Request information about the locations, hazards, and shutdown procedures for aircraft systems as well as safety instructions and precautions.
Most airlines produce videotapes that can acquaint you with the characteristics of their fleet. These tapes are excellent training tools and are available on request from the airline’s administration or training facility. These documents and videotapes can be used to develop simple, condensed aircraft prefire and evacuation plans that can be reproduced and distributed to emergency responders. The prefire plans are excellent quick reference guides, and they will reduce the need for memorization and guesswork.
Aircraft walkthroughs are mandatory for airport firefighters or first responders. This hands-on training is critical and perhaps even the key to a comprehensive training program.
Airlines have excellent hands-on training facilities throughout the country. Flight crews are required to attend annual emergency training classes to sharpen their skills. Most major airline training centers have mock-up door simulators identical to the doors found aboard their aircraft. During recurrent training, each flight attendant is required to demonstrate proficiency in operating all door mock-ups under simulated emergency conditions. Their knowledge of how to operate all doors must be current, since they probably will serve aboard each aircraft in their fleet during their career. If you are close to one of these training facilities, contact the director of training and ask to attend this valuable training.
Understanding how the broad spectrum of aircraft doors, emergency exits, and evacuation systems operate is a challenge. There is no easy way to acquire this knowledge. Initial and recurrent up-to-date classroom instruction, annual aircraft walkthroughs and tours, continuous hands-on training, and quality aircraft prefire plans are the keys.*