The price of pushing the limits of research has always been measured in human lives. But it is a mistake not to ask if the price has to be so high * The article appeared in issue 4 (April May 2003) of the journal World of Science and Technology - Scientific American, published by Ort. Presented courtesy of the journal editors
By: Gion Rani Editor-in-Chief Scientific American
In an age where space flight has become almost routine, it is easy to forget the dangers of rocket flight and the difficulty of dealing with the wild heights of the Earth's atmosphere," said President George W. Bush in his announcement about the Columbia shuttle disaster during its reentry into the atmosphere.
"These astronauts knew the dangers, and faced them willingly, knowing that they had accepted a noble and noble purpose for their lives." One of the sentiments expressed by many after the disaster is that such tragedies remind us that the price of advancing the frontiers of research has always been measured in human lives.
Of course it's true, but it's a mistake to assume things like that, without checking. One hundred and thirteen times we launched a shuttle into space. Twice we witnessed terrible failures and the loss of all crew members. Can this be considered a reasonable risk?
Based on the history of missile launches, this is about the risk we should expect. According to Theodore Postel, professor of science, technology and national security policy at the Massachusetts Institute of Technology, even the most reliable system in the space vehicle assembly (the rocket booster) suffers from a failure rate of approximately two percent. At this rate, if "shuttle launches continued at the rate of five missions per year, we should expect a Columbia or Challenger style disaster once a decade."
NASA's stated estimate is that the risk of failure on any given mission is 1:145, that is 0.7 percent, and the engineers and scientists working in the NASA service are working relentlessly, with supreme effort, to reduce this number to zero, but a number that the shuttles will cut is working against them: Columbia alone took off into space 28 times), if we simply accept this NASA risk estimate, 0.7 percent per mission, then the chance of losing one shuttle out of 113 missions is approximately 55 percent,
No one knows for sure what the best rate is for calculating the chances of harming the shuttle, because risk estimation is a complicated and generally uncertain science, the study of the history of the shuttle program does not provide us with any reason to think that the number could have been much higher, although it is possible to glorify the space shuttle as a work of art
An engineering thought, but it can also be presented as the equivalent of a camel, which, as the well-known saying goes, is a horse designed by a committee.
When the idea of the shuttle was raised in the late XNUMXs, there was talk of a fixed reusable vehicle for launching small crews cheaply
to a space station, and their return. The shuttle and the station were intended to serve as intermediate stops on the way to Mars, that initial venture of a space station was canceled in the meantime, but the shuttle continued to exist, with a less defined purpose. But soon they found new tasks for her. The researchers wanted the ability to perform more and more experiments in orbit, so they added an incentive to perform them.
The use of the shuttle to launch commercial satellites was seen as a source of income, the Pentagon wanted the shuttle to carry military satellites, and the cargo hold was enlarged even more. The gradual accumulation of missions changed the shape of the shuttle, increasing its trunk and turning it into a hybrid of a racing car and a truck. The engineering implications were not negligible. It turned out that the construction of a reusable space vehicle is more difficult than first thought.
Neither this history nor the estimates of the disaster were kept a secret. Rather, they filled the media in the early years of the shuttle program, when they made headlines after the explosion
The shuttle Challenger. That ferry, as we know, crashed, even a damaged seal. Physicist Richard Feynman and the Rogers Commission, which investigated the accident, convincingly demonstrated that the failure was due to poor planning and poor supervision within the program itself. The problem was identified, the malfunction was corrected, and the shuttle program became much safer thanks to this, and yet "it is possible that one of the side effects of the discovery of that defective seal was the distraction of the public from the fact of its existence to outrages that do not necessarily involve an error in judgment or slobbery." The shuttle's multi-tasking, as reflected in its design and operational profile, presents basic ballast problems that can practically be chalked up as guarantees for future disasters.
Of course, if the Azbadan of Colombia returned and sharpened the focus on this issue, "Yes, the recognition of a loss rate of two percent does not change anything. The loss of human life (and equipment) in such a way is perhaps more reasonable than the idea that space exploration is an uplifting pursuit that deserves a great civilization to engage in it. The presence of man in space symbolizes, apart from anything else, the curiosity of our species and the urge that nestles in the depths of Kafsham to advance the limits of their investigations further and further - and perhaps this is one of the noblest motives of humanity, in the previous centuries bold ships sailed across the expanses of the oceans in search of new continents, and their chances of returning Life was much better.
Surely the astronauts themselves knew the dangers, and perhaps we, as a society, should not shy away from them now.
But if the lives of the astronauts are precious in our eyes, as a moral sin if we do not return and examine the fundamental questions of why we gamble with human life, and whether we can improve the odds of the bet, one dead crew in ten is a high price for a manned space program whose goals are unclear and whose scientific value is not high Always.,
One of the possible courses of action is to continue with the shuttles we have, while eliminating every possible obstacle in any way we can find, to investigate the causes of shuttle accidents and to increase the safety margins in a prudent manner, here are some ideas that are worth looking into: while in orbit and fix them; installation of escape pods for quick evacuation; Making sure all the shuttles could dock with the space station and many other things.
Reducing the mission teams and replacing shuttle flights with unmanned missions could also reduce the risk. In short, we must review all the benefits and all the costs, and only then decide how much we are willing to spend to prevent another Columbia disaster.
A more extreme alternative would deal with the lack of clear and precisely defined goals of NASA's manned space program, even if this would ultimately require us to abandon today's shuttles and the space station still under construction.
In the absence of such goals (and their appropriate funding), there is almost no possibility to evaluate the established plan, with its advantages and disadvantages. The new goals that will be set before NASA may be as ambitious as landing a man on Mars, or they may be relatively simple such as promoting tourism in space. In any case, it is better for this body to focus on building the vehicles suitable for the task.
Even in such a new space program the risk of a terrible disaster will continue to exist. It is hoped that it will be much lower than the existing risk on ferries, but there are no guarantees. Still, the extent of the disaster may be smaller. Perhaps the number of flights in which humans participate will be smaller, and perhaps we will find comfort in knowing that if the vehicle failed, it was not because of the design requirements that were imposed on it while increasing the essential risk.
Such a program would be expensive, and it should be assumed that it would not initially yield much scientific knowledge. (The Apollo program also did not bring much benefit to science in its early stages). But in this plan, there will be a wiser balance between the value of human life and the scientific and spiritual value of space travel. We must respect the heroism of the astronauts, and not desecrate it by demanding that they risk their lives for goals that were not properly considered.
