What the best-dressed astronaut is wearing

A mission to find out what suits the modern spaceman is about to be launched. Peter Bond looks at the competing designs

Later this month, providing Nasa can repair faults that forced a launch postponement last Saturday, two American astronauts will don their bulky pressure suits, enter the airlock and float out into the cargo bay of the space shuttle Endeavor. But they will have little time to admire the view. One of their tasks will be to evaluate modifications to the life-protecting suits as part of the preparations for assembling the international Alpha space station later this decade.

Space fashions have come a long way since March 1965, when Alexei Leonov became the first human to step into the emptiness of space. Leonov's life was threatened when his primitive garment ballooned outwards, preventing him from returning inside his capsule until he lowered the suit's internal pressure.

Thirty years on, spacewalking, or extravehicular activity (EVA) as it is officially known, is relatively commonplace. Well over 100 such excursions have been successfully completed. Politics have also changed. Americans and Russians are no longer competitors in a hard-fought space race but colleagues in a new co-operative venture to build Alpha.

The end of the Cold War has enabled spacesuit designers from both East and West to compare notes. Although the design of all EVA suits is determined by a number of constraints, including durability, flexibility, comfort and cost, the requirements of space travellers have been met in rather different ways by the engineers of the two space powers. Nasa favours a mix-and-match approach, with five sizes of upper torsos; Russian cosmonauts are simply selected to fit the available suits.

One of the few Westerners to have worn both Hamilton Standard's shuttle suit and the Orlan suit of the Russian Zvezda company is James Asker of Aviation Week & Space Technology. He found that it was quite straightforward to push his legs into the soft "trouser" section of the US suit, but inserting the head and upper body into a tight-fitting upper section was much more complicated. It involved raising his arms above his head and inserting them into the sleeves while pushing his head into place. Joining the two pieces of the suit was even more difficult.

In contrast, getting into the Orlan suit was simple. With the suit hanging from a rack, he swung open a door at the back of the aluminium casing on the upper torso and worked his legs down into the pants. He then put his arms down the sleeves and worked his fingers into the gloves. The rear door was closed and sealed using a lever at his waist.

Once inside the suit, the astronaut is protected from the hostile environment by the equivalent of a $10m personal spacecraft. Designed to operate in the vacuum of space, the suit has an impermeable inner lining that envelops the entire body and maintains air pressure at a constant level.

Russian designers have always favoured a suit that contains oxygen at a pressure of 5.8psi (pounds per square inch) compared with 4psi for the American suit. This means that American suits are more flexible and hand movements less tiring, but this is offset by the astronauts spending a lot more time purging their bloodstreams of nitrogen before they can venture outside so that they do not suffer from the bends.

Differing mission requirements have also influenced the final design. Russian EVAs are often shorter and centred around maintenance tasks outside the Mir space station. The suits remain on the station for long periods, so on-orbit servicing must be easy. As a result, many of the "frills" such as a drink bag, food and a urine collector have been omitted from the Orlan suit. American astronauts only fly for up to two weeks, but they are expected to carry out a wider range of tasks, including satellite repair and scientific experiments.

Both suits have an excellent safety record, although this has been achieved through radically different approaches. "While the US suit is designed to be failsafe," says Mr Asker, "the Russians designed the Orlan suit with a redundant approach for all life-critical systems. For example, it has dual pressure bladders, except in the gloves, where two bladders would diminish tactile sensing too severely."

Creating the perfect glove for EVA has proved extremely difficult. One astronaut described his experience in repairing a satellite as "surgery in boxing gloves". Providing adequate manual dexterity is only half of the problem. Spacesuits must be capable of protecting the wearer from extreme heat in direct sunlight and bitter cold in shadow or darkness. Last February, frozen fingers forced the astronauts Bernard Harris and Michael Foale to curtail their spacewalk as outside temperatures plunged to minus 87C.

Further improvements will obviously be required before assembly of Alpha begins. Two methods of fighting the cold will tested on Endeavor's next mission. One involves a bypass in the suit's liquid cooling system. "At present, the crew member anticipates when he will be working less hard and turns down his cooling system," says Richard Wilde, EVA systems engineering manager with Hamilton Standard. "The bypass will allow the fluid flow to stagnate so that it no longer takes out body heat."

The other innovation involves a battery-powered heater located just outside the pressure portion of the glove. "It will raise the temperature only a few degrees and add only a few watts of heat, but it should improve the comfort there significantly," says Mr Wilde.

Since both sides will be working side by side during the shuttle-Mir programme and the construction of Alpha, it would clearly be advantageous for US and Russian EVA suits to use as much common hardware as possible. Earlier this year, Hamilton Standard suggested upgrading its suit so that it could operate at the same high pressure as the Orlan, but this is unlikely to be funded in the current financial situation. "It's not necessary to get the station built," says Mr Wilde. "There will be two sets of suits and two sets of airlocks on board Alpha, one for US or Russian use and one solely for the Russians."

Nevertheless, some changes are going ahead to bring both suits into line. Nasa has budgeted about $5m over the next two years to develop compatible radio systems, foot restraints, safety tethers and tool carriers.

Looking further ahead, a new generation of suits is on the drawing board. Although they resemble the "Michelin man", the intention is to make them lighter, less bulky, more flexible and longer-lasting than existing suits. Minimal effort will be needed for movement since the hard suit maintains a constant volume, so the internal pressure remains constant no matter how much the wearer changes posture. Arm and leg movements will be eased by construction of extra sections in the sleeves and trousers, each mated to free-moving rotary joints. It may eventually be possible to replace the bulky thermal overgarment with thermal coatings applied directly on to the metallic structure.

Whether the suits will ever become operational remains in doubt. "There has been a lot of encouragement from the highest levels," says Mr Wilde, "but the money has not yet been authorised."

people Emma Watson addresses celebrity nude photo leak
Katie Hopkins appearing on 'This Morning' after she purposefully put on 4 stone.
peopleKatie Hopkins breaks down in tears over weight gain challenge
Boris Johnson may be manoeuvring to succeed David Cameron
peopleHis band Survivor was due to resume touring this month
people'It can last and it's terrifying'
In this photo illustration a school student eats a hamburger as part of his lunch which was brought from a fast food shop near his school, on October 5, 2005 in London, England. The British government has announced plans to remove junk food from school lunches. From September 2006, food that is high in fat, sugar or salt will be banned from meals and removed from vending machines in schools across England. The move comes in response to a campaign by celebrity TV chef Jamie Oliver to improve school meals.
Arts and Entertainment
Life and Style
fashionModel of the moment shoots for first time with catwalk veteran
Life and Style
fashionPart of 'best-selling' Demeter scent range
ebooksAn unforgettable anthology of contemporary reportage
Tom Cleverley
footballLoan move comes 17 hours after close of transfer window
Alexis Sanchez, Radamel Falcao, Diego Costa and Mario Balotelli
footballRadamel Falcao and Diego Costa head record £835m influx
Life and Style
fashionAngelina Jolie's wedding dressed revealed
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Web Developer/UI Developer (HTML5, CSS3,Jquery) London

£55000 - £65000 per annum: Harrington Starr: A Global Financial Service Organi...

Data Scientist (SQL, PHP, RSPSS, CPLEX, SARS, AI) - London

£60000 - £70000 per annum: Harrington Starr: A prestigious leading professiona...

C# Web Developer (C#, MS Dynamics CRM, SQL, SQl Server) London

£40000 - £50000 per annum: Harrington Starr: A Global Financial Service Organi...

Oracle developer- (Oracle, PL/SQL, UNIX/LINUX) - Trade- London

£50000 - £70000 per annum: Harrington Starr: One of the global leaders in prov...

Day In a Page

'I’ll tell you what I would not serve - lamb and potatoes': US ambassador hits out at stodgy British food served at diplomatic dinners

'I’ll tell you what I would not serve - lamb and potatoes'

US ambassador hits out at stodgy British food
Radio Times female powerlist: A 'revolution' in TV gender roles

A 'revolution' in TV gender roles

Inside the Radio Times female powerlist
Endgame: James Frey's literary treasure hunt

James Frey's literary treasure hunt

Riddling trilogy could net you $3m
Fitbit: Because the tingle feels so good

Fitbit: Because the tingle feels so good

What David Sedaris learnt about the world from his fitness tracker
Saudis risk new Muslim division with proposal to move Mohamed’s tomb

Saudis risk new Muslim division with proposal to move Mohamed’s tomb

Second-holiest site in Islam attracts millions of pilgrims each year
Alexander Fury: The designer names to look for at fashion week this season

The big names to look for this fashion week

This week, designers begin to show their spring 2015 collections in New York
Will Self: 'I like Orwell's writing as much as the next talented mediocrity'

'I like Orwell's writing as much as the next talented mediocrity'

Will Self takes aim at Orwell's rules for writing plain English
Meet Afghanistan's middle-class paint-ballers

Meet Afghanistan's middle-class paint-ballers

Toy guns proving a popular diversion in a country flooded with the real thing
Al Pacino wows Venice

Al Pacino wows Venice

Ham among the brilliance as actor premieres two films at festival
Neil Lawson Baker interview: ‘I’ve gained so much from art. It’s only right to give something back’.

Neil Lawson Baker interview

‘I’ve gained so much from art. It’s only right to give something back’.
The other Mugabe who is lining up for the Zimbabwean presidency

The other Mugabe who is lining up for the Zimbabwean presidency

Wife of President Robert Mugabe appears to have her sights set on succeeding her husband
The model of a gadget launch: Cultivate an atmosphere of mystery and excitement to sell stuff people didn't realise they needed

The model for a gadget launch

Cultivate an atmosphere of mystery and excitement to sell stuff people didn't realise they needed
Alice Roberts: She's done pretty well, for a boffin without a beard

She's done pretty well, for a boffin without a beard

Alice Roberts talks about her new book on evolution - and why her early TV work drew flak from (mostly male) colleagues
Get well soon, Joan Rivers - an inspiration, whether she likes it or not

Get well soon, Joan Rivers

She is awful. But she's also wonderful, not in spite of but because of the fact she's forever saying appalling things, argues Ellen E Jones
Doctor Who Into the Dalek review: A classic sci-fi adventure with all the spectacle of a blockbuster

A fresh take on an old foe

Doctor Who Into the Dalek more than compensated for last week's nonsensical offering