It is understandable that some astronauts feel “safety must be the single highest priority in human spaceflight” [“NASA Forgets Key Lesson from Columbia Accident,” Jan. 20, page 19]. 

That attitude may have been reasonable during the Apollo project, and even for the space shuttle, when spaceflight was new and most things were being done for the first time. In 2014, however, after almost 60 years of experience, Vance Brand et al. and the Columbia Accident Investigation Board are wrong. Safety is not, and cannot be, the highest priority on a new frontier if humanity wants to successfully get there. 

One of the key reasons human spaceflight has moved so slowly, and cost so much, is that “safety” is given far too high a priority. In the United States, we are unwilling to tolerate the death of a single astronaut without the expenditure of untold hundreds of millions or billions of dollars covering every possible failure mode before flight, and again after every accident. If the New World had been explored that way, the United States would not exist.

In retrospect, from a safety point of view, the space shuttle turned out to be a bad design. It is obvious now that placing the crew cabin on the side of its rocket was not wise. 

That was not obvious when the shuttle was developed. We have learned the lesson: All of the five human spacecraft under serious development in the United States place the crew vehicle on top of the rocket. 

We learned this lesson through experience, by developing and flying the shuttle — and by losing astronauts. Even if we spend every cent devoted to spaceflight trying to anticipate failure modes, it is not possible to anticipate every potential mistake, even apparently obvious ones. 

Blue water shipping loses hundreds of sailors to accidents every year. We don’t stop shipping every time a sailor dies. We accept that seafarers have a dangerous occupation, improve safety as much as is consistent with getting the job done at reasonable cost, and pay crews accordingly.

Any human spacecraft we develop and fly often enough will have failures that kill astronauts and passengers — just like failures involving aircraft and automobiles kill pilots, drivers and passengers. In fact, for no better reason than convenience, as individuals and as a society, we tolerate far higher levels of risk with the routine use of private automobiles than we would by taking the train or by flying. 

Safety must be an important criteria: We need to have a realistic chance of getting to our chosen destinations, however that chance is defined. But if we wish to explore, safety cannot come at all costs. There must be money left over to accomplish the missions we have assigned ourselves.

A human expedition to Mars is a popular goal for much of the space community. Let’s set aside the question of whether such a challenging and risky mission is a wise choice immediately following international space station construction and operations in the relative safety of low Earth orbit. 

As has been the case with past human exploration on Earth, even with limitless funding, the chances of survival for the first human expedition to Mars are likely to be quite low. A near-unlimited budget for going to Mars — the Apollo model — is not in the cards. While we all hope the United States’ financial health continues to improve, it is unlikely to return to the halcyon post-World War II days of the 1950s and 1960s, when most of the technology used in Apollo was developed. We live in a different world now, one where spaceflight is more routine and must be more affordable. If we are going to Mars, most likely we must do so without spending much more money in real terms than the post-Apollo NASA traditionally receives (substantially less than $20 billion per year, with approximately a third going to human spaceflight). The acceptance of greater risk must be part of the cost-versus-value equation.

In the Commercial Crew Program, NASA has rightly emphasized setting standards and relying on competition to encourage safety — just like the Federal Aviation Administration (FAA) does with commercial aircraft development. The FAA does not dictate to Boeing or Airbus everything they must do to ensure safety, or insist that unlimited funds be spent. Boeing’s 787 was a new technology, high-risk development, and mistakes that could have cost lives were made that neither Boeing nor the FAA caught in advance of routine flight. When they were discovered, on operational vehicles, the aircraft were grounded while the lithium-ion battery problems were contained. 

The alternative was not to develop or fly the 787 and continue with 767 technology — which has its own risks. Competition, too, is important. Airbus is developing the more conservative A350 in response to the 787, and airlines will have a choice between two approaches to balancing performance, cost and risk, among other factors.

After 53 years, human spaceflight in the nations with the most experience — the United States and Russia — must be treated in a similar way. NASA should fund a minimum of two commercial crew contenders, and preferably all three, to ensure competition and multiple approaches to achieving routine orbital transport — even if the budget provided by Congress is below the optimum levels required for historic levels of safety. 

Experience throughout the transportation industry has shown that the best way to ensure increased reliability, and thus safety, is more frequent operation. Russia achieves the extraordinary reliability of the Soyuz not with money but through relative simplicity and flying a similar vehicle often over many decades. Space Exploration Technologies is using a similar philosophy in its Falcon 9 launch vehicle — so far, with notable success. 

Subtle problems are caught through repetition, and the lessons learned can be applied routinely to the production line. In a fixed budget environment, flying often means keeping the cost per flight down. Astronauts may be lost early on, but in the long term you will get more spaceflight with safer spacecraft.

Exploring a new frontier has never been, and never will be, easy or safe. If today’s astronauts want to be astronauts, and fly, they have to accept less funding and greater risk than they have in the past. The alternative, for astronauts as for the rest of us, is to price ourselves out of the game and stay safely at home. Is that really what we want? 

Donald F. Robertson is a freelance space industry journalist based in San Francisco. For further examples of his work, see

Donald F. Robertson is a retired space industry journalist and technical writer based in San Francisco.