The crew of the spacecraft Columbiad was a bit unusual: three men, two dogs and a couple of chickens, fired into lunar orbit from the Florida coast. Their craft was the epitome of fashion–Victorian fashion, that is–with thickly padded walls, a circular divan and a dome-shaped roof, a far cry from today`s space shuttle Columbia or any other modern spacecraft.
The three adventurers and their crew were the stars of Jules Verne`s classic 19th-Century novels, ”From the Earth to the Moon” and ”Round the Moon.” ”Why cannot we walk outside like the meteor?” exclaims Michel, one of the voyagers. ”What enjoyment it would be to feel oneself thus suspended in ether, more favored than the birds who must use their wings to keep themselves up!”
Michel and his friends lacked space suits, but today`s astronauts have no such laments. Protected by a multilayered, pressurized space suit, the most complex garment ever made, they routinely venture into space.
Although space travel is relatively recent, the idea of space suits is not, says Linda Neuman Ezell, an historian and associate curator for manned space flight at the Smithsonian`s National Air and Space Museum in Washington. ”In fact, there are startling similarities between some early science fiction space suits and the suits of today.”
The forerunner of the space suit was the pressure suit, designed for more earthbound adventurers: deep-sea divers, balloonists and mountain climbers. In 1911, Dr. J.S. Haldane, a well-known English respiratory physiologist, led an expedition to Pikes Peak in Colorado to study the effects of low atmospheric pressure on climbers. Following his trip, he proposed the use of an oxygen-pressurized suit to allow mountain climbers to ascend to high altitudes.
Haldane`s research led in 1933 to England`s first pressure suit ensemble, a modified diving suit. (The factors involved in safe ascension from the depths of the sea to its surface are the same as those that apply to survival at high altitudes.) Mark Ridge, a 27-year-old balloonist and daredevil from Dorchester, Mass., tested the suit in a low-pressure chamber where a simulated altitude of 90,000 feet was reached.
During the 1930s, aviators around the globe competed for altitude and speed records, but the fliers were restricted. Above 40,000 feet, the limit for unpressurized flight, the lungs cannot absorb sufficient oxygen to replenish the bloodstream.
The world`s first practical flight pressure suit grew out of the long-distance, high-altitude flying interest of noted American aviator Wiley Post. In 1934, Post asked the B.F. Goodrich Co. of Akron to help him develop a pressure suit. ”For all serious altitude flying,” Post said at the time,
”it is necessary to maintain pressure around the body by sealing off space and pumping air into it.” This principle remains the basis for all subsequent pressure suit development.
Post`s first pressure suit, built for about $75, used a rubberized parachute fabric and an aluminum helmet. But when the suit was tested in a low-pressure chamber, it sprang a leak, then burst. Modifications were made, but suit number two fared little better. While trying it on, Post, who had gained a few pounds since the first suit, got stuck, and the suit had to be cut off.
Success came with the third suit, which consisted of three layers–long underwear, an inner rubber bag to contain oxygen under pressure and an outer cloth-contoured suit. On March 15, 1935, Post, wearing the new suit, flew from Burbank, Calif., to Cleveland in 7 hours, 19 minutes, breaking previous speed records.
As flight technology developed from airplanes to jets to spacecraft, the requirements for protecting pilot and crew changed as well. From the early 1940s on, when it became possible to pressurize aircraft cabins, the pressure suit became a secondary back-up system. It was only with the first space walk in 1965 that the suit became a primary protection system. During these two decades, however, at least 30 major types of pressure suits were designed and constructed.
The T-1 suit, built for the Air Force in 1949, protected pilots against loss of consciousness should the aircraft cabin suddenly decompress. That same year, with Navy support, Goodrich improved Post`s pressure suit by reducing its bulk and increasing its mobility and ventilation. The new suit was called the Mark IV.
The XH-5 pressure suit, made in 1943 by Goodrich for the Army Air Forces, resembled today`s space suit more than the others. Its designer, Russell S. Colley, figured out how to improve the suit`s mobility after observing the crawling motions of a tomato worm. The XH-5 suit had bellows modeled after the segments of the worm`s body.
Although both pressure suits and space suits must provide protection, mobility, comfort and minimum bulk at light weight, the space suit must also protect against the impact of micrometeoroids (small, potentially dangerous meteor particles) and the extreme temperatures of space.
”Mercury, the first manned space program, proved that man could survive in space,” Ezell says. ”The Mercury suit was actually a modified Mark IV suit.” But the 21-pound pressurized suit was never needed. It served primarily as an emergency back-up.
The Gemini project gave astronauts the opportunity to work in space. In 1965, Gemini 4 astronaut Edward H. White II became the first American to
”walk in space.” His four-layer suit weighed 23.5 pounds.
”The Apollo program brought new problems,” Ezell says. ”The environment on the moon was largely unknown. The tasks that the astronauts would perform were more sophisticated and complex than those performed on Mercury or Gemini. And the astronauts would not be hooked up to the mother craft via the umbilical cord used in Gemini.”
These problems were solved with the Apollo 20-layer suit and its backpack, known as the ”portable life-support system.” The system provided the same vital functions as the spacecraft, but it was also portable and allowed freedom of movement.
Modifications to the 190-pound Apollo suit were often made following each flight. ”The Apollo 17 astronauts, for example, wanted a way to scratch their noses while on the moon,” Ezell says. ”Since they couldn`t remove their helmets to do it, a piece of Velcro was put inside the helmet for that purpose.”
ILC Dover, a small engineering company in Frederica, Del., has made all space suits for NASA since the Apollo program–some 200 suits. The company is filling an order for 44 suits, which will be used during the next 15 years.
”It takes 500,000 man-hours and $150,000 in materials and labor to make one space shuttle suit,” ILC official Donald C. Johnson says. ”When you add the engineering costs, the price tag jumps to about $2.5 million for one suit.”
Each 11-layer space suit is made entirely by hand, sewn from a variety of synthetic fabrics. Every thread, every needle and bolt is inspected and documented in strict technical order. ”Once a stage is reached, a plant inspector certifies the work,” Johnson says. ”Then a government inspector must sign off on it. Each suit weighs about 100 pounds–and I sometimes think another 100 pounds of paperwork goes with it. But the suit is the occupant`s entire world when he or she is outside the spacecraft. Without it, the astronaut would be dead.”
In the Apollo days, each astronaut was given three suits–for training, for the flight and as a back-up–and each suit was custom made. A space shuttle astronaut gets just one suit and even that is not for keeps. Unlike the Apollo suit, the space shuttle suit is modular in construction. Its 20 parts can be mixed and matched to make hundreds of combinations. ”When an astronaut is selected,” Johnson explains, ”he or she is measured and the corresponding parts are taken off the shelf to make the suit. After the flight, the suit is cleaned and goes back on the shelf to be used again.”
The shuttle suit can be adapted to fit either sex, from a 100-pound, 5-foot-2-inch woman to a 200-pound, 6-foot-2-inch man. Although most suit parts come in various sizes, helmets come in one size only, and boots come in two, Johnson says, ”big and bigger.”
ILC is developing a prototype suit for the next space adventure: the space station. The outer shell of the ZPS, or ”zero prebreathing suit,” is made of metal alloys and aluminum to protect astronauts against solar radiation. Dubbed the Tin Man by ILC employees, this throwback to the age of armor weighs several hundred pounds.
”But in a weightless environment,” Ezell says, ”weight is immaterial.”
