LT Harris Steinke was the inventor of the "Steinke Hood" a device that aided escape from a sunken submarine. The Steinke Hood, an inflatable life jacket with a hood that completely enclosed the wearer's head, trapped a bubble of breathing air. An individual escape suit, the Steinke Hood was designed and tested in 1961, when inventor LT Harris Steinke escaped from the USS Balao. An advancement over its predecessor, the Momsen Lung, the Steinke Hood was standard equipment in all submarines of the United States Navy throughout the Cold War.
The new device for buoyant ascent from greater depths than possible with the Momsen Lung was developed and tested by Lt. Harris Steinke and his staff at the Groton CT escape tower. It featured a hood attached to the top of the life jacket which captures air vented from the jacket under decreasing pressure so that the escapee can breathe during a long ascent. The Steinke hood was tested in trial runs from a bottomed submarine at 318 feet off the Dry Tortugas.
The long-standing method of escape from United States Navy submarines, the buoyant ascent using the Steinke Hood, was introduced in 1962. Pressurized buoyant ascent training ceased in the United States in the 1970s due to concerns associated with financial costs and health risks. Operating procedures for escaping from US Navy submarines had remained essentially unchanged since World War II.
The orange fabric-breathing hood is attached to the orange buoyancy chamber. The buoyancy chamber has a connection that allows the chamber to be charged with compressed air through a charging manifold in the rescue/escape trunk. During ascent to the surface, expanding air from within the buoyancy chamber passes through two (2) relief valves and into the hood to ventilate it and keep it expanded.
To escape from a disabled submarine, several sailors would enter an escape trunk, which is then isolated from the submarine by closing an inner hatch. The escapees don an appliance known as the Steinke hood, which is a life jacket with an attached hood that allows continuous breathing. The hood is plugged into an air-charging system, and the escape trunk is flooded with sea water and compressed to ambient sea pressure. The outer hatch of the trunk is opened, and the escapee leaves the trunk and is carried to the surface by the positive buoyancy of the hood. Air expanding in the hood vents to the sea during ascent. The risk of air embolism is small if the escapee breathes normally.
This system has several drawbacks, however. If compression of the escape trunk is slow and the depth is great, the risk of DCS is significant. The escapees operate the trunk themselves, which may be difficult if they are frightened or compromised by contaminated air, carbon dioxide, hypoxia, pulmonary oxygen toxicity, or nitrogen narcosis. If an escapee is caught in the trunk, it becomes unusable by others; and unless rescue is immediate when the escapee reaches the surface, the chance of survival is small because no thermal protection is provided.
As early as 1974, one study highlighted significant biomedical shortcomings in the escape system: hypothermia, nitrogen narcosis, hypercarbia, barotrauma, and decompression sickness. These shortcomings were attributed to the method of escape and operating procedures. Furthermore, the current method of submarine escape was no longer practical, because the Steinke Hood provided no thermal protection for the escaper during the escape and while awaiting recovery. Accordingly, citing emerging technology and recent studies, by 1996 researchers at the Naval Submarine Medical Research Lab presented biomedical-based recommendations for enhancing survival of escapers by a) overhauling current submarine escape systems and procedures and b) substituting existing thermal protection suits for the Steinke Hood.
Soon after the turn of the century the Navy was rapidly replacing the Steinke Hood rescue device with the new Submarine Escape Immersion Equipment (SEIE), a combined whole-body suit and one-man life raft that provides protection against hypothermia in freezing water. The Steinke Hood was not sufficient to protect Sailors from environmental exposure once they reach the surface.
The Steinke hood Buoyancy Chamber is made of orange, neoprene-coated, nylon fabric. The chamber is constructed so that it forms a collar that allows the wearer to pass his head through it during use. When inflated, the buoyancy chamber provides the positive buoyancy necessary for ascent to the surface. While on the surface, the chamber provides the escapee with approximately 14 kilograms (30 pounds) of additional positive buoyancy. During ascent to the surface, air in the pressurized chamber expands and passes through two (2) relief valves on the top of the chamber. This air passes into the breathing hood and supplies air to keep water out of the hood.
A fabric Breathing Hood is attached to the collar portion of the buoyancy chamber. A clear, T-shaped plastic face shield in the hood provides visibility. A neck ring made of neoprene-coated nylon stretch cloth connected to the base of the collar. The neck ring prevents air from escaping from around the escapee's neck and out of the breathing hood during ascent. An oral inflation device consisting of a tube and an oral inflation check valve is installed on the front of the buoyancy chamber. The valve can be secured in the closed position by rotating a knurled ring counterclockwise toward the mouthpiece on the valve. This prevents accidental opening of the valve, which could deflate the buoyancy chamber. A plastic snorkel valve with an attached neoprene mouthpiece in the breathing hood allows the escapee to breathe outside air while wearing the hood. When the valve is rotated to the OPEN position, the escapee can breathe outside air using the mouthpiece. When the valve is rotated to the CLOSED position, no air can pass through the mouthpiece.
A Charging Adapter and Check Valve is installed on the lower part of the appliance. The charging adapter is used with quick disconnect hose couplings on the escape appliance air charging manifold in the rescue/escape trunk. The check valve prevents air from escaping from the buoyancy chamber after the appliance is charged with compressed air and the charging hose is disconnected from the escape appliance.
Two Buoyancy Chamber Pressure Relief Valves are installed on top of the buoyancy chamber under the breathing hood on either side of the appliance. The valves are exposed to the difference in pressure between the buoyancy chamber and the interior of the breathing hood. During ascent to the surface, the valves automatically open to allow air expanding in the buoyancy chamber to vent into the hood. The valves have the following fixed open and reseat values: open at 12.1 kiloPascals (kPa) (1.75 pound-force per square inch gauge [psig]) maximum and closed at 10.3 kPa (1.5 psig) minimum. The valves have a flow capacity of 0.16 cubic meter (5.5 cubic feet) per minute at a differential pressure of 20.7 kPa (3.0 psig).
Two Breathing Hood Pressure Relief Valves are located on the sides of the breathing hood. The valves are exposed to the difference in pressure between the inside of the hood and the surrounding seawater. The valves regulate the air pressure in the hood during ascent to the surface. A zipper is installed on the base of the hood and attaches it to the collar of the buoyancy chamber. The zipper allows enough of the hood to be detached from the buoyancy chamber so that the escapee can throw it behind his head when on the surface. A protective flap is provided on top of the zipper to keep it from chafing the escapee's neck. A pocket is provided on the front of the appliance for storing a whistle, sea-dye marker, and nose clip. The whistle and nose clip have lanyards attached to a metal grommet in the accessory pocket. The sea-dye marker is attached to the same grommet using a cord 1.2 meters (4 feet) long and 1.6 millimeters (1/16 inch) in diameter.
An adjustable waist belt of nylon webbing with an attached metal buckle holds the lower section of the appliance around the wearer's waist. The belt prevents the appliance from sliding over the wearer's head during use. A pad on the belt protects the wearer from chafing caused by the metal buckle rubbing on the skin. The toggle line is a nylon cord, approximately 0.9 meter (3 feet) long, with a wooden handle at the end. The toggle line is attached to the waist belt and is stowed in a small pocket there. The toggle line provides a way to lift the escapee into a boat or tie escapees together once on the surface.
Each submarine escape appliance is supplied with a rubber-coated cloth pouch in which the appliance is stored. The pouch protects the appliance from damage during storage. The personnel marker light is attached to a loop on the upper portion of the appliance as described in Naval Ships' Technical Manual (NSTM) Chapter 077, Personnel Protection Equipment. As described in NSTM Chapter 077, strips of reflective tape 51 millimeters (2 inches) wide are glued to various areas of the appliance (as shown in NSTM Chapter 077, figure 594-4-3) to make the escapee more visible while on the surface. The reflective tape is applied following the procedures in NSTM Chapter 077.
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