Orland-D Credit - © Mark Wade

US spacesuits have been pressurized at 0.30 bar (30% earth sea level pressure), but because the gas in the suit is 100 percent oxygen instead of 20 percent, the person in a spacesuit actually has more oxygen to breathe than is available at an altitude of 3,000 m without the spacesuit. At the US suit pressure, before leaving to perform tasks in space, an astronaut has to spend several hours breathing pure oxygen before proceeding into space. This procedure is necessary to remove nitrogen dissolved in body fluids and thereby to prevent its release as gas bubbles when pressure is reduced; a condition commonly called "the bends". Russian and future NASA suits are pressurized to 0.56 bar, shortening the pre-breathing period to half an hour.

A spacesuit also shields the astronaut from bombardment by micrometeoroids and insulates the wearer from the temperature extremes of space. Without the Earth's atmosphere to filter the sunlight, the side of the suit facing the Sun may be heated to a temperature as high as 120 degrees C; the other side, exposed to darkness of deep space, may get as cold as -160 degrees C. Paradoxically, the suit's life support system has to remove the heat and moisture generated by the sweaty working astronaut. This is usually accomplished by circulating cool water through an undergarment worn next to the astronaut's skin. Heat overload of space suits caused several crises on the first space walks in the Voskhod and Gemini programs.

Early US space suits were adapted from pressure suits designed for pilots of high altitude military and experimental aircraft. The first suits designed from the beginning for use in space were the American A7L and Soviet Krechet suits. These were designed for walking on the moon during the space race of the 1960's. They provided the basis for those used aboard space station and shuttle missions.

The search for the perfect suit continues. It would seem the next major step will be suits suitable for use on the surface of Mars. These will have very different design criteria than those used in zero-G.

	Mark Ridge Suit	The first full pressure suit was made by a London diving suit firm for the American balloonist Mark Ridge. Ridge never flew in it, but English pilots broke two world aircraft altitude records with a derivative of the suit in 1935-1936.
	Wiley Post Suit	B F Goodrich made a full pressure suit for pioneering aviator Wiley Post, who used it to make ten stratospheric flights in 1934-1935.
	Draeger Suit	Germany's Draeger-Werke developed a hard shell full pressure suit for the Nazi government in 1935-1945.
	Escafandra Estratonautica	Spanish Colonel Don Emilio Herrera Linares designed and built a full pressure suit in 1935, which was to have been used during an open-basket balloon stratospheric flight scheduled for early 1936. The Spanish Civil War intervened.
	Garsaux Suit	The first French full pressure suit was designed by Dr Paul Garsaux with the backing of the Potez Airplane Company in 1935.
	Pezzi Suit	The first Italian pressure suit was used between 1934 and 1937 by Italian pilots Pezzi and Negroni to break altitude records with the Caproni 161, 161bis and 113 aircraft.
	Henry PPS	J P Henry and D R Drury designed the capstan partial pressure suit and exposed subjects to 24,000 m. Three models were tested. These would be the basis of the post-war Dave Clark rocketplane suits.
	Tomato Worm Suit	Project MX-117 full "tomato worm" pressure suits were developed and tested in the United States between 1940 and 1943.
	T-1	David Clark Company developed Dr. Henry's original capstan partial pressure suit. The first operational capstan partial pressure suits (PPS) were produced in custom sizes for early rocket powered X-Plane test pilots, by the David Clark Company. They produced the T-1 capstan pressure suit in standardized sizes made of nylon cotton twill. It was chamber tested to 32 km and subsequently flown in a variety of high altitude aircraft. The T-1 Capstan suit (5 to 1 ratio), incorporated an anti-G suit, no chest bladder, and came in 12 standardized sizes for fighter aircraft.
	BIS Space Suit	In 1947 R A Smith presented a series of papers to the British Interplanetary Society. This space suit was the concept for earth orbit work.
	Model 4	The Model 4 Full Pressure Suit was developed for D-558-2 Douglas Skyrocket test pilots. It was first flown by Navy test pilot Marion Carl for a 26 km altitude record flight. Integrated arm scye bearings (non-sealed) provided improved mobility. Custom sizing was required to tailor the suits to individual test pilots. This was the forerunner of the X-15 full pressure suit and was developed by the David Clark Company and Scott Crossfield at NACA.
	S-2 Pressure Suit	The S-2 was a modified capstan partial pressure suit evolved from the T-1 with no anti-G and no chest bladder. It was produced in 12 sizes for bomber aircraft. It used the K-1 helmet, A2 adapter, and C-1 assembly with an F-1 regulator (0.87 l bottle at 120 bar) as an oxygen source. Fired automatically by aneroid at 13 km. Used T block to hook aircraft oxygen system with C-1 assembly backup. Hawks pressure compensated valve in K-1 helmet assembly. David Clark Company.
	KKO-3	The KKO-3 was the first mass-produced Soviet partial pressure suit. It was very similar to the US MC-3 of the same period.
	Lines of non-extension suit	Developmental partial pressure suit concept by Arthur S Iberall while at the Rand Corporation.
	Mark I ELSS	The USAF Mark I Extravehicular and Lunar Surface Suit was tested during 1958-59, and led to subsequent development of more refined and satisfactory RX-series "Moon Suits" for NASA.
	RAF Jerkin System	The RAF Jerkin System comprised a pressure vest used with a P/Q mask and anti-G suit. Several variations included unsleeved, sleeved and integrated garments proven for short term protection to 18 km. Mk-1 Taylor and M.L. clam shell pressure helmets were used with the sleeved variant for short term protection to 30 km.
	S-4	The S-4 was a modified S-2 partial pressure suit, no anti-G, chest bladder incorporated for ease of breathing. Also incorporated abdominal bladder for individuals who experienced abdominal difficulties, e.g. weak inguinal rings.
	Mark 1 Mod III	While the USAF concentrated on partial pressure suits, the US Navy worked on omni-environmental full pressure suits to combine altitude and immersion protection. The Mark 1 Mod III Suit-Omni-Environmental full pressure Suit was the result, and was made in many modifications over a ten year period by B F Goodrich.
	MC-1	A modified S-2 partial pressure capstan suit with chest breathing bladder, 12 sizes, high altitude, fighters and bombers, smaller capstan in torso area, pressure gloves, K-1 or MB-5 helmet, David Clark Company.
	Canadian PPS	The Canadian Waistcoat-Mask/Vest/G-Suit was a partial pressure assembly. The Canadians studied variants of this assembly as far back as the early 1940's. Newer variants were studied for short term protection to altitudes of 24 km with the G suit pressurized to 4 times breathing pressure.
	MB-1	MB-1 & 2 were experimental test pilot's partial pressure suits using the K-1 helmet. Chest and abdominal bladders were added to produce the G4A anti-G suit for the Air Defense Command, which provided 5-6 protection to 30 km, used no capstans, and with the MA-1 helmet rather than the K-1.
	MC-3	A capstan partial pressure suit with horizontal shoulder zipper, sewn breaklines, no anti-G, height/weight sizing criteria, used on bomber and reconnaissance aircraft, came in 12 sizes. The MA-2 helmet was by ILC Dover. Many variants of this suit were used for special projects such as the XS-1, X-1A, and X-2 rocket aircraft, the Project Man High balloon flights and Kittinger's Project Excelsior stratosphere parachute jump from 31.3 km in1960.
	C-1A	A partial pressure capstan suit with incorporated anti-G bladders for USN fighter aircraft, 12 standard sizes.
	C-4	A partial pressure capstan suit, with vertical shoulder laces, adjustable break lines, anti-G suit, MG-1 Berger Bros. gloves, MA-2 helmet by ILC Dover. Suits by produced by David Clark and Berger Brothers, adapters by Airlock, seat kit and oxygen panel by Firewell. 12 sizes.
	CSU-2P	Developmental dual capstan partial pressure suit for altitude protection by Berger Brothers. Used pressure socks and double capstan for looser fit.
	Lombard Suit	Developmental partial pressure suit developed by Dr. Lombard of Northrop.
	Mark IV Model 3 Type I	By the early 1960s, the US Navy had progressed through a series of developmental models of the full pressure suit that would ultimately take final form in the Mark IV, Model 3, Type 1, a production suit which US Navy aircrew wore on high altitude flights during its cold weather operations.
	MC-2	The XMC-2 full pressure suit developed in the mid-1950s jointly by Wright Field personnel and the David Clark Company for X-15 pilots. It represented a major advance in pressure suit technology, serving as prototype for those used later by Mercury and Gemini astronauts. The suit included an integrated parachute harness. It required custom sizing and was produced in many variants by the David Clark Company as Model S794-5. It allowed the wearer freedom of movement while keeping him comfortable and protected in the event of cabin pressure failure or emergency ejection from the X-15 at extreme altitudes. The suit incorporated a ventilation layer to cool the user and an outer heat resistant layer. The helmet was built by the Bill Jack Company and contained oxygen equipment, microphone and earphones, and an anti-fogging feature.
	MC-3A	A modified MC-3 suit with vertical shoulder laces and adjustable break lines. Produced by David Clark and Berger Brothers. MA-2 helmet by ILC Dover.
	MC-4A	A modified MC-4 with height/weight fit for fighter aircraft, anti-G suit. Suits produced by David Clark, Berger Brothers and Seymour Wallace. The MC-3 and MC-4 series of suits used the MB-5, MA-2 (ILC Dover) and MA-3 (Bill Jack) helmets.
	Horizon Space Suit	For sustained operation on the lunar surface Project Horizon advocated a 'body conformation suit' having a substantial outer metal surface.
	A/P 22S-2	The David Clark XMC-2-DC prototype, although still in need of substantial development, evolved into the MC-2 suit and then into a standardized Air Force high altitude, full pressure garment known as the A/P 22S-2. This provided greater mobility than the Goodrich A/P22S-3 full pressure suit. 4 layers, 8 sizes, suit controller, oxygen regulator inside helmet, outer layer nylon/polyurethane, dacron link net restraint second layer, third layer silicon impregnated nylon / neoprene pressure bladder, inner fourth diffusion layer was oxford weave. Many variants, used in bombers, the X-15, and other high altitude aircraft.
	A/P 22S-3	USAF version of the USN Mark IV suit (B. F. Goodrich and Arrow Rubber Company). Full pressure, two layers, oxygen regulator exterior of helmet, 12 torso sizes, 7 gloves sizes, 2 helmet sizes, pressure relief set in the 0.23 to 0.27 bar range. Helenca coated neoprene material used in mobility areas, nylon impregnated chloroprene in non-mobility areas.
	Mercury Space Suit	The Mercury spacesuit was a custom-fitted, modified version of the Goodrich U.S. Navy Mark IV high altitude jet aircraft pressure suit. It consisted of an inner layer of Neoprene-coated nylon fabric and a restraint outer layer of aluminized nylon. Joint mobility at the elbow and knees was provided by simple fabric break lines sewn into the suit; but even with these break lines, it was difficult for a pilot to bend his arms or legs against the force of a pressurized suit. As an elbow or knee joint was bent, the suit joints folded in on themselves reducing suit internal volume and increasing pressure.
	KKO-5	The KKO-5 partial pressure suit was introduced for pilots of Mach 2 aircraft such as the MiG-21 and Su-9 at the beginning of the 1960's. It represented the largest production run of any pressure suit model.
	Sokol SK-1	For the "Vostok" spacecraft, Zvezda developed the KP-V-3A pilot seat, which provided for an emergency escape in the ascent phase and normal ejection of the cosmonaut before landing (there was no soft landing system on Vostok). The SK-1 full-pressure space suit, equipped with an auxiliary life support system and survival features, provided for cosmonaut safety under all expected environmental conditions of flight and after landing.
	G1C	NASA Gemini prototype full pressure suit, closed loop. The G-1C lead to the G-2C, G-3C (IVA suits), G-4C (both IVA and EVA suit), and G-5C with a soft head enclosure for the 14 day Gemini 7 mission.
	G2G	The BF Goodrich space suit was developed in competition with the Dave Clark G2C suit for Project Gemini. It was not flown.
	G4C	Dave Clark G4C flight suits were designed for wear by Gemini astronauts. Spacesuit designers followed the U.S. Air Force approach toward greater suit mobility when they began to develop the spacesuit for the two-man Gemini spacecraft. The suit was used for the first American spacewalk on Gemini 4, and on all subsequent flights except the Gemini 7 long-duration mission.
	Macuh Suit	Closed cell foam suit concept by Macuh Laboratories, USAF/NASA study, report MLTRD-62-13.
	S-939	Full Pressure Suit for the X-20A Dyna-Soar program.
	S901/970	A-12, YF-12A and SR-71 full pressure suit with integrated subsystems, parachute harness, automatic flotation system, urine collection device, redundant pressure control and breathing system, thermal protective garment. Custom fitted or in 12 standard sizes and various models.
	A4H	ILC Dover and Hamilton Standard full pressure suit, Contained a secondary bladder and restraint with a wrist cuff/dam for NASA/HSD (1963-1964), modified A4H suit for NASA-AMES (1964-1965). 1964-65 AX5L -NASA Apollo suit prototype, IVA, ILC Dover
	G2C	The Dave Clark G2C was the prototype IVA space suit for project Gemini. None were flown. The flight versions were G4C and G5C.
	AX-Series	Between 1964 and 1968 two hard suit assemblies were developed at NASA-ARC, identified as the AX-1 (Ames Experimental) and AX-2. These suits were the first to demonstrate multiple bearing technology. The AX-3 was an 0.5 bar suit, 23 kg, 0.5 to 0.7 bar operational pressure, with improved mobility and was completed in 1977. The program culminated in the development of the prototype AX-5, an all hard suit for high pressure application and zero prebreathe in the 1980's. The AX-5 shared common design goals with the ILC Mark III. For example, they had to be easy to get into and out of, be comfortable to wear, and allow adequate mobility and range of motion for the jobs to be performed. Both were designed to be altered to fit different size astronauts
	AX5L	NASA Apollo suit prototype, rated for intravehicular activity only.
	G3C	Dave Clark G3C initial Gemini production flight suits were worn aboard Gemini 3, and by the spacecraft commanders of Gemini 6 and 8..
	RX-Series	RX-1 Litton full pressure hardsuit, weighed 40 kg, rolling convolute joint technology, 2-plane enclosure, modular sizing, 1964. Followed by RX-2, 40 kg. in 1964 and RX-2A, 36 kg in 1964. RX-3 and RX-4 versions were down to 27 kg in 1966. The suits were pressurized to 0.34 bar but adaptable to 0.48 bar with an oxygen/nitrogen mixture. The RX-5A was the final configuration of this series.
	A1C	For the initial Block I Apollo missions a modification of the Gemini G4C suit was to have been flown. After the death of the Apollo 1 crew on the pad, Block I missions were cancelled and the suit never flew. The A1C was a full pressure suit featuring a closed loop system and custom sizing.
	AES Series	Developmental suit hybrids using laminated fabrics, rolling convolutes, toroidal joints, sealed bearings, and modular sizing. Versions by both AiResearch and Litton.
	AX-1C	Full pressure, Apollo Block II prototype suit for both IVA/EVA by the David Clark Company. Not put into production.
	Berkut	Berkut was a modified Vostok Sokol space suit. The needs of the cosmonaut were supplied not through the umbilical cord, but rather through a simple open-cycle environmental control system. Oxygen, used for both breathing and cooling, was contained in a metal backpack. A relief valve vented the suit into space, carrying away heat, moisture, exhaled carbon dioxide, and unconsumed oxygen. There were two relief valve pressure settings - 0.27 atmosphere or 0.40 atmosphere. Sufficient oxygen was carried for 45 minutes of depressurized activity. It was only worn on the Voskhod 2 flight, when Leonov had great difficulties in getting back into the airlock due to the suit's stiffness. It was only after switching to the lower relief valve pressure setting that, bathed in sweat, he was able to get the hatch of the inflatable airlock closed.
	CSU-4/P	A bladder type partial pressure suit, with quick don, 8 sizes, separate garment (CWU-4/P) for immersion protection, inverted neck seal, HGU/8/P helmet, front entry, get-me-down altitude protection, no ventilation initially. Gloves were needed for longer term exposure to high altitude. Used by Kittinger in USAF stratosphere jump, later used by Japanese.
	CSU-5/P	A modified bladder type partial pressure CSU-4/P suit with integrated wet suit.
	EFA-30	French partial pressure capstan suit using full pressure buffet protective helmet.
	G5C	The David Clark G5C lightweight space suit was developed for long duration Project Gemini missions. It was designed to be easily removed during flight and to provide greater comfort than the standard Gemini space suit. Astronauts Frank Borman and James A. Lovell used suits of this type during their 14 day Gemini VII mission in December 1965.
	Grumman Moon Suit	A favorite of Life magazine in the 1960's, this Grumman / Space General design for extended lunar surface operations allowed the astronaut to withdraw his arms from the flexible manipulators and work within the pressurized 'cabin' of the can enclosing his upper torso and head.
	S-100	Pressure suit which introduced many modifications from the early MC-3A capstan suits. A torso bladder used a redundant full pressure controller and full pressure helmet (1972), 12 sizes, used for high altitude reconnaissance aircraft, exterior cover of various colors worn over pressure suit, This was the last capstan partial pressure suit in operational service - retired with the U-2C aircraft in 1989.
	S-1029	Developmental bladder type partial pressure suit.
	Space Sled	Marquardt developed a sled design in the mid-1960's for maneuvering in the vicinity of a spacecraft. The space sled approach was dropped in preference to the shuttle manned maneuvering unit.
	TFX	Prototype bladder type partial pressure suit with a separate Anti-G suit valve. APL program with Navy and ILC Dover.
	Type B	Full pressure suit designed by R. E. Simpson, and developed by Baxter, Woodhouse and Taylor Ltd. for the Royal Air Force. Used Windak full pressure helmet or lightweight head enclosure (handbag) developed by the Royal Aircraft Establishment.
	Boyles Law Suit	Concept by Otto Schueller, patented by Davis, Moore, Ritzinger and Whitmore at USAFSAM. Passive suit design with pressurization bladders containing closed gas cavities and a breathing bladder connected through the helmet regulator and aneroid-operated visor. Studies to 23 km using the system. Further developed by David Clark Company.
	DU-1 Rocket Belt	This rocket belt was planned for use aboard a follow-on Voskhod mission in the 1960's. The mission was cancelled and the belt never tested.
	G4C AMU	This space suit was designed to provide thermal protection to astronauts using the Astronaut Maneuvering Unit (AMU). The suit was basically a David Clark Gemini G4C suit with leg covers of aluminized material added to prevent heat damage from the AMU thrusters. Astronaut Eugene Cernan wore the suit during the Gemini IX-A mission in June 1966 in an unsuccessful attempt to test the AMU during extravehicular activity.
	Gemini EMU	Vought developed the EMU, which was to have been flown in the Gemini program. This design approach led to the Space Shuttle's MMU (Manned Maneuvering Unit) was put into operation.
	Republic Moon Suit	This was a Republic Aviation design for a hard space suit for extended operations on the lunar surface. It was very popular in Life magazine in the 1960's -- and coincidentally resembled a suit from a Republic Pictures serials of the 1940's.
	A/P22S-4	Full pressure suit replacement for the A/P22S-2, 8 sizes for use in bomber and reconnaissance aircraft. Evolved from the original MC-2 design.
	Yastreb	The Yastreb suit was the first suit designed in the Soviet Union for extra-vehicular activity. Design began in 1965, and it was initially to be worn on the aborted Soyuz 1/2 1967 crew transfer mission. It was only worn on the Soyuz 4/5 mission, the EVA on Soyuz 7/8 having been cancelled when the spacecraft failed to dock. Yastreb's regenerative life support system was small, designed to be worn on the chest or on the shin, in order to allow the cosmonaut to get through the relatively small Soyuz orbital module hatch. A complex pulley system was used to provide the suit with flexibility.
	A7L	Hamilton Standard had overall development responsibility for the Apollo suit and associated portable life support system. A subcontract was awarded to International Latex Corporation for development of this suit. After suit development was completed, the production contract was awarded to International Latex, and the initial suit was designated A5L. The A6L design incorporated a thermal/ meteoroid garment. This was never flown. Following the Apollo fire, the suit was redesigned to eliminate flammable materials and was designated A7L (designation A8L was never used).
	IMLSS	In 1968-69 Hamilton Standard developed this Integrated Maneuvering Life Support System (IMLSS) for the USAF Manned Orbiting Laboratory program. IMLSS could operate on an umbilical from MOL or disconnect and fly independently from the station. IMLSS experience greatly influenced design of the later Shuttle EMU.
	NAZ-3	The NAZ-3 emergency-landing kit was used in cosmonaut training in all seasons and extremes of temperature, and on all manner of terrain: mountains, steppes, tundra, desert, taiga, and in water. The survival kit was designed to gain the attention of rescue crews rather than for long-term use, containing enough supplies for three men over a 72-hour period. The triangular shape of the carrying cases allowed them to be secured snugly in the cramped space between the seats of the cosmonauts onboard the Soyuz craft.
	S1010	A special variant of the S901, designated the S1010 PPA, was developed specifically for use in the U-2R aircraft in the mid-1960s. This special projects full pressure suit was equipped with integrated subsystems including parachute harness, automatic flotation, redundant pressure control and breathing system, thermal protection. Custom fitted or in 12 standard sizes. Various models used in the U-2R.
	Swedish Jerkin	Partial coverage garment - two pressure flying suit with diaphragmatic bladder, used with high pressure mask equivalent to A-13 with Hardman kit. Anti-G suit at 3.2 times breathing pressure, get-me-down protection to 20 km. Mask automatically tightened by gas filled expansion pad in back of helmet.
	A9L	Two hard-shell, constant-volume suits entered development for the Apollo Applications Program. An extravehicular suit was being developed by Litton Industries, and an intravehicular suit was being developed by AiResearch Corporation. Due to budget cutbacks, it was decided to use the A7LB suit instead for Apollo J series lunar landing missions, Skylab and Apollo ASTP.
	Krechet	The Krechet spacesuit was designed by the Zvezda OKB for use on the lunar surface. It consisted of flexible limbs attached to a one-piece rigid body / helmet unit. The suit was entered through a hatch in the rear of the torso. The exterior of the hatch housed the life support equipment. Maximum operation time was ten hours.
	MOL Space Suit	Space suit designed to support launch/re-entry and Extra-Vehicular Activity (EVA) aboard the USAF Manned Orbiting Laboratory. Developed from 1965-1969, when MOL was cancelled.
	Baklan	The Baklan full-pressure suit was developed by Zvezda for the crew of high altitude strategic aviation aircraft..
	EIS/OES	Developmental 0.54 bar Emergency Intravehicular Suit (EIS) and Orbital Extravehicular Suit (OES) programs were conducted by NASA in the 1970's. The fabric mobility joint technology developed here was the basis for the Shuttle EMU development.
	S1030	Upgraded SR-71 full pressure suit, link net with integrated subsystems.
	VMSK-4	The VMSK-4 was a partial pressure immersion suit developed for Soviet Naval Aviation pilots.
	Sokol-K1	After the Soyuz 11 tragedy, in which all three unsuited cosmonauts died in a decompression accident, the Soviets scrambled to produce new IVA suits. To abbreviate design time, the new drawings were based on the Sokol suit used on the Vostok missions. A prototype of the new suit, known as Sokol K1, was produced in 1971, with workshop drawings going through further revisions and refinements from August 1971 through March 1972. The suit was tested on the ground in 1972 and in space onboard Soyuz 12 in September 1973. From that point onward, the Sokol-K1 and its subsequent generations were used on all Soyuz flights for the launch, docking, and descent phases. In an emergency the 10 kg suit could protect the wearer in open space. The suit included the 2AC-9000-0 pressure suit without the integral helmet, 2AC-9001-00 inner pressurized bladder, and 2AC-9009-00 soft helmet
	Space Activity Suit	Prototype for a Mechanical Counter Pressure suit made up of six layers of elastic material accompanied by a full bubble helmet. The goal was to improve the range of activity and decrease the energy cost of work associated with wearing conventional gas filled pressure suits. The suit would also be half the weight, simpler, and not endanger the astronaut's life if punctured.
	Skylab AMU	One of several extravehicular mobility devices tested by the Skylab astronauts within the spacious station.
	Skylab AME	Another of the EVA maneuvering units tested by the Skylab astronauts within the capacious station.
	A/P22S-6	Full pressure suit replacement for the A/P22S-4. 12 sizes, for bomber, reconnaissance and fighter aircraft.
	A/P22S-6A	Modified A/P22S-6 suit to add urine collection device with other material and hardware changes.
	Chibis	The Chibis suit was in use from 1971 (Salyut 1) to the ISS era. The basic function was the opposite of a g-suit. Instead of pushing blood and fluids away from the legs back toward torso and head, the Chibis suit drew fluid back down to the legs. This was to counteract the tendency of fluids to accumulate in the head in weightlessness.
	Penguin	The Penguin Prophylactic Body-Loading Suit, in use from 1978-present, looked like the standard Russian blue inflight suit, but had additional elastic bands and pulleys that created artificial force against which the body could work, ameliorating the deterioration of muscles and bones that occurs in long-term zero gravity. The Penguin suit was routinely worn during all long-term flights.
	HAFO	High Altitude Flying Outfit. Prototype developmental full pressure suit with integrated thermal/pressure/chemical defense/immersion and Anti-G protection, ILC Dover.
	HAPS	High Altitude Protective System (HAPS). Hybrid get-me-down system assembled for NASA Dryden Flight Research Center test pilots. Consisted of cut-away anti-G suit with dual bladders (altitude and G), torso counter-pressure garment (Jerkin) and British P/Q type oxygen mask. Breathing pressure to 70 mm Hg at 18 km. Combined effort between DFRC (Barnicki), Edwards AFB (Melvin), RAFIAM (Ernsting), USAFSAM (Morgan), and David Clark Company.
	PHAFO	Prototype High Altitude Flying Outfit. Prototype partial pressure suit by David Clark to integrate altitude, thermal, immersion, chemical defense and anti-G protection, Non-conformal (Dome Type) full pressure helmet with oxygen mask.
	Chinese Space Suit	Chinese astronauts have been shown training in a variety of space suits since 1978. The earliest suits resembled space shuttle EES suits. The later suits, after a technology agreement with Russia, resembled Soyuz Sokol suits.
	Orlan	The Orlan spacesuit was used for Russian EVA's on Salyut, Mir, and the International Space Station. It was designed by the Zvezda OKB, and derived from the Kretchet suit intended for use on the lunar surface.
	EES	The initial series of shuttle flights were equipped with specially adapted SR-71 ejection seats for the two crew. The crew were provided with space suits, derived from the USAF SR-71 suits, which provided them with some protection in the event of ejection or cabin depressurization. The suit was a modified S1030A with an anti-G system. After the initial flights, and until the Challenger disaster, the crew was provided only with oxygen masks.
	S1031	The S1010 and several S1010 dash variants were later replaced by a further advanced model, the S1031 PPA. The S1031 special projects full pressure suit came in 12 sizes and was used in the TR-1 and U-2R. In the early 1980s efforts to produce a standard single suit capable of being used by both SR-71 and U-2 crews, yielded the S1031C suit, replacing earlier suits on an attrition basis.
	Shuttle EMU	The Space Shuttle Extravehicular Mobility Unit (EMU) was a reusable space suit. For a particular crew member and mission it would be tailored from a stock of standard-size parts. Many variants were fabricated over the years. The suit was certified for eight EVA's, and its modular design allowed it to fit 90% of the male/female population. It featured an integrated hard torso with a portable life support system, RF sealed bladder, fabric mobility joint elements, waist bearing, and improved pressure gloves.
	TR-1	Prototype full pressure suit developed by ILC Dover for the TR-1 aircraft.
	TLSS/ALSS	Tactical Life Support System. Developed by the USAF and Boeing/Gentex et. al. to provide get-me-down protection from 18 km. Incorporated many new features - including a modular mask, vest, and anti-G suit ensemble integrated to provide PBG for high G maneuvers and PBA for altitude. G trousers provided 4 times the breathing pressure from a molecular sieve oxygen concentration system. There were updated variants of this system in the United Kingdom, Canada, Sweden, and an Advanced Oxygen System for France.
	Shuttle MMU	The MMU Manned Maneuvering Unit was designed for maneuvering by astronauts untethered from the shuttle. It was used on several satellite retrieval missions in the early 1980's. After the shuttle disaster, use of the unit was discontinued on safety grounds.
	AX-5	The AX-5 high pressure, zero prebreathe hard suit was developed at NASA Ames Research Center in the 1980s. It achieved mobility through a constant volume, using a hard metal/composite rigid exoskeleton design.
	MK ZPS	NASA Zero Pre-breathe full pressure Suit developed to preclude the need for denitrogenation prior to EVA. The Mk-I ZPS was the precursor to the Mk-3 and was based on shuttle suit geometry with several rigid components for use at a pressure of 0.56 bar. The MK-3 contained both machined/cast aluminum and composite graphite Hard Upper Torso and modular sections for arms and legs to fit 90% of male and female population. Used rolling convolutes at shoulder, and waist; bearings in hips; fabric elbows, knees and ankle joints, ILC Dover, Airlock Corp. and Hamilton Standard.
	Shuttle LES	After the Challenger disaster, it was decided to provide the crew with pressure suits to be worn during launch and re-entry. The Shuttle launch/entry suit (LES) was a partial-pressure suit designed to protect shuttle crew in the event of loss of cabin pressure at altitudes up to 30 km. It also served to insulate the crew from cold air or water temperatures after a bail out from the shuttle. The suit was a modified CSU-4/P with non-conformal full pressure helmet, dual neck dam, integrated exposure suit, parachute harness and flotation equipment. During re-entry, an anti-G protection system consisting of pressure bladders in the legs and lower abdomen fought pooling of blood in the lower body after prolonged exposure to microgravity. The suit also protected the crew from any contamination in the cabin atmosphere. The LES was replaced by the Shuttle ACES suit from 1995 on.
	SPK	The Soviet Union developed a manned maneuvering unit and flew it from Mir in 1990. The UMK weighed 218 kg. In case of a malfunction, it remained connected by a tether attached to a winch on an EVA mast installed near the Kvant-2 exit hatch of Mir. The UMK was used on only two EVA's, at distances of up to 45 m from the station. Unlike the shuttle MMU, it was only flown tethered to the station. Like the shuttle MMU, it was retired after a few tests.
	AHAFS	Advanced High Altitude Flight Suit. High pressure (0.40 bar) full pressure suit developed for the USAF to increase mobility at higher operating pressures.
	APS	The Advanced Pressure Suit (APS) was a bladder type partial pressure suit designed and developed by Northrop and ILC Dover for the F-23 Advanced Tactical Fighter. Integrated high altitude, anti-G, Immersion, thermal air cooling and chemical defense protection. Suit bladder had pressure booties and oronasal/full head pressure for PBA and PBG. Breathing bladder/helmet/suit pressurized to 0.24 bar for altitudes above 11 km and 60 mmHg breathing/0.70 bar suit at +9z for anti-G protection. 6 each purchased by USN.
	KKO-15	Introduced in 1989, the KKO-15 protective partial pressure suit was used by pilots of Russian high-performance combat aircraft. It featured better performance and G-protection than earlier models .
	Sokol-KV2	Improved version of the Sokol IVA suit developed for use aboard Soyuz T.
	Strizh	The Strizh full-pressure suit was developed for the Buran program. It was qualified to protect the cosmonaut in ejections from the spaceplane at altitudes up to 30 km and speeds of up to Mach 3. The suit and the K-36RB (or K-36M-11F35) ejection seat were tested during ascent of a Soyuz booster in a series of five Progress launches (Progress 38 through 42) in 1988-1990.
	S1034	The David Clark model S1034 PPA was an advanced lightweight full pressure suit which replaced the S1031C (common SR-71/U-2 design) suit and offered significant performance improvements, including enhanced pilot comfort, ease of donning and reduced stress-fatigue. First flown on 20 June 1991, the S1034 PPA was meant to ultimately replace all earlier David Clark S-series suits in use by the US Air Force (which were designed for an approximate 10 year use/life-span). The suit featured integrated life support subsystems to include breathable pressure bladders.
	NASA Mark III	The NASA Mark III was an advanced NASA space suit design of the 1990's. The Mk III hybrid advanced suit assembly consisted of a hard upper torso, brief and hip transition elements, and rolling convolute shoulder, waist and hip abduction/adduction joints. It also offered upper arm, shoulder, hip, waist, and ankle bearings. The Mk III was intended to be pressurized at the relatively high pressurization of 0.56 atmospheres.
	F-22 PPS	Partial pressure suit development for F-22 Aircraft. Get-me-down partial pressure ensemble combining Mask/Vest/uniform pressure anti-G garment for protection to 18 km. USAF contractors include Boeing, ILC Dover, META and Helmets Ltd.
	ISS EMU	Upgraded version of the Shuttle EMU with improved sizing and mobility, 25 EVA certification, Hamilton Standard and ILC Dover.
	ACES	The Shuttle Advanced Crew Escape Suit (ACES) replaced the Launch/Entry Suit (LES) from 1995 on. The ACES fulfilled the same functions as the LES. It was designed to protect shuttle crew in the event of loss of cabin pressure at altitudes up to 30 km, but unlike the LES it was a full-pressure suit. It also served to insulate the crew from cold air or water temperatures after a bail out from the shuttle. During re-entry, the same anti-G protection system used in LES, consisting of pressure bladders in the legs and lower abdomen, fought pooling of blood in the lower body after prolonged exposure to microgravity. The suit also protected the crew from any contamination in the cabin atmosphere. ACES also provided a liquid cooling undergarment.
	ESA	Prototype full pressure suit for the European Space Agency (ESA), produced by Dornier, Dassault, Zodiac, et. al., 0.40 bar.
	EVA 2000	Prototype full pressure suit effort between ESA and USSR to upgrade the Orlan DMA.
	D-1	The D-1 (S1035X) space suit assembly was developed to provide a functional all-soft suit technology demonstrator prototype model to be used for mobility system testing and evaluation.
	M-Suit	In the fall of 1998, two soft suit prototypes were delivered to NASA by two companies, ILC Dover and David Clark. ILC Dover's M-Suit operated at a pressure of 0.26 atmospheres and weighed 30 kg. In comparison to the Apollo and Shuttle suits, the M-suit had a greatest range of motion and the smallest joint torque. It utilized as government furnished equipment the shuttle helmet, neck ring, and wrist disconnects and was designed to interface with the shuttle liquid cooling and ventilation garment, communications carrier assembly, and gloves.
	Bio-Suit	The Bio-Suit was a novel approach to spacesuit design that used and biomedical breakthroughs in skin replacement and materials to replace the bulky conventional "balloon" spacesuit with a 'second skin' approach to provide light weight, flexibility, and comfort in all extraterrestrial environments. It provided life support through use of mechanical counterpressure applied to the entire body through a tight-fitting suit, excepting a helmet for the head. The inner layer of the Bio-Suit could be sprayed on, and disposed of, together with dirt and dust, after each EVA. The external layers would include embedded "wearable technologies" that would be tailored to the environment and mission.