NEW SKYLAB FEARS

Press, Volume CXIII, Issue 33230, 21 May 1973, Page 13

NEW SKYLAB FEARS

(N.Z.P.A.-Reuter —Copyright) HOUSTON, May 20. Fears of toxic gases, and trouble with the Skylab’s refrigerators, have brought extra urgency to the United States Space Agency’s efforts to save its expensive space station mission. While the astronauts who still hope to form Skylab’s first crew, Captain Charles Conrad, Dr Joseph Kerwin, and Commander Paul Weitz, flew to Alabama to practise, in a special water tank, emergency space - walks, scientists and mission-plan-ners today studied the new gas threat. Dr Royce Hawkins, of the medical operations section at the Houston Space Centre, expressed fears that the polyurethane foam lining the wails of the space station’s main living area—the “orbital workshop” — may be venting lethal toleunedi-isocya-nata gas, as well as cyanide and carbon monoxide. Ground tests indicate that this might well happen under the prolonged high temperatures prevailing in the workshop since Skylab lost

a vital thermal protection shield and half her electrical power after the launching last' Monday. It is planned to issue the crew with special filtermasks and colour-coded gassensors to combat the threat. Dr Hawkins says that the problem can be overcome if I the astronauts can get the! temperature down, and if the air inside the spacecraft is ; changed. In the neutral buoyancy water tank at the Marshall Space-flight Centre in Huntsville, Alabama, the crew is practising ways of stretching a special “sail” along one side of Skylab, to protect her from the sun. Yet another design of sunshade is now being tested for possible deployment from inside the Skylab once the crew are aboard. It is a variety of the “umbrella” dej vice already well in the running for inclusion among the various repair kits, that, if all is well, the crew will take up with them next Friday. One umbrella uses telescoping rods, and the other, spring - actuated unfolding rods. An inflatable shield, activated by a nitrogen gas bottle, has been successfully ground-tested at Huntsville.

Measuring 20 by 24 feet, it is much like a liferaft, with pressurised booms at the extremes and thermal material stretched between. Once deployed, it would float; about 20 inches from the sun-facing side of Skylab.

The two main devices under consideration both rejquire space-walk activities. The “sail” would be put in place from the outside by a crewman standing up in the hatch of the Apollo ferry spacecraft. If this fails, the crew will board Skylab, and one astronaut will crawl out through her space-walk hatch to push a stiffened canopy along the side.

While the design and manufacture of the “sunshades” proceeded last night, mission control reported what it described as “a possible hitch” in the cooling system of the workshop, which keeps the freezers—and the all-impor-tant food supplies for the three crews due to man Skylab over an eight-month period—below zero degrees Fahrenheit. It also chills the drinking water, cools electronic parts when experiments are in progress, and provides cool air for the atmosphere controls. Mission control says that, for unexplained reasons, the main system, or “coolant loop,” has suddenly switched over to a secondary, back-up system. However, the flight director, Mr Neil Hutchinson, says that the problem is not yet considered serious. Motor-cycle curb Motor-cycles with an engine capacity of more than 100 c.c. will be banned in Bermuda after a five-year phasing out. —Hamilton, May 20.