In defense of the Shuttle

July 22, 2011 - Reading time: 10 minutes

Historical note - this was perhaps not my most coherent or eloquent blog post, but I was pretty angry.  I'm not editing it, but I will revise history a bit to say that I haven't regarded Phil Plait as a reasonable person for many years.

OK fine I edited it, but only slightly.  It's been almost 20 years now; I think my writing has improved.

Amos Zeeberg wrote an essay published at Discover Magazine that takes a critical view of the Space Shuttle.

It's probably obvious that I'm a big fan of the Shuttle program.  And in these blinkered times, it's not really unusual to see such one-sided criticism in places that would normally be forums for reasonable discussion.  But it is a bit disheartening to see people like Phil Plait, who normally strikes me as a smart and reasonable person, refer to such an article as "fair."  So I feel compelled to respond to some of the less reasonable things that Amos says:

Now that Atlantis is safely on the ground and astronauts will never again face the risk of flying in a space shuttle, maybe we can at last take a clear-eyed look at this disappointing episode in our nation's history.

Well, he starts out swinging.  At least we know what his view on the matter is.  He seems to feel that space travel is perfectly safe in other vehicles.  He ignores, for example, the Soyuz program's two missions that ended in loss of crew: Soyuz 1 (1967) and Soyuz 11 (1971).  So the Soyuz program has lost 2 out of 110 missions and the Shuttle program lost 2 out of 135.  As far as space vehicles go, the Shuttle fleet isn't really out of the ordinary.

But this also brings up a more philosophical point: exploration has always been a dangerous matter and people have always died in those efforts.  If we choose not to explore space because it's risky, we fail.  As for disappointment, that single notion leads me to not take anything this guy says seriously.  To call the program a disappointment completely ignores the scientific and technological advances that came out of the Shuttle program.  Plenty of people have been discussing those lately.  I mentioned it briefly here.

The most important thing to realize about the space shuttle program is that it is objectively a failure. The shuttle was billed as a reusable craft that could frequently, safely, and cheaply bring people and payloads to low Earth orbit. NASA originally said the shuttles could handle 65 launches per year; the most launches it actually did in a year was nine; over the life of the program, it averaged five per year.

Here he develops his own set of criteria and then dismisses the program as a failure based on it not living up to those criteria.  Yes, the Shuttle fleet did not fly as often as was originally promised.  Yes, it cost more than was originally promised.  A lot has been said about the costs and it's likely that the original cost estimates were overly optimistic with the goal of getting the program funded at all.  As for the number of launches, though it didn't launch as many times as Amos would have liked, it did launch 135 times over 31 years for an average of just over 4 launches/year (including the couple of years that were skipped after the losses of Challenger and Columbia).  Compare that to just 110 Soyuz launches over 45 years, just under 2.5 launches/year.  The Orbiters also fit more than double the crew as a Soyuz, so far more people have flown in Shuttles as well (852 vs 258: >3 times as many people).  In the last decade, there were 28 Shuttle launches and 24 Soyuz launches.  And again, the Shuttle program had other goals that are harder to quantify: a return on investment with scientific and technological achievement.  Oh, but we're ignoring those points.

The failure rate was two out of 135 in the tests that matter most.

Again ignoring the competition, which (by the same test) fares worse.  That is not to be flippant about the deaths of Shuttle crews, only to point out that it's no MORE dangerous than other crewed spacecraft.

It seems likely, in retrospect, that the project was doomed for a variety of reasons, including the challenging reusable spaceplane design and the huge range of often conflicting demands on the craft.

The Shuttle Orbiter was a more complex spacecraft than any other.  But the "huge range of often conflicting demands" was made possible by that complexity.  The Shuttle Orbiter made many things possible that are still not possible with any other spacecraft, existing or in development.  So rather than "dooming" the project, these demands were making use of available features.  If NASA had decided, for example, not to use the Orbiter's airlock to allow multiple crew members to perform EVAs while other crew members were in a shirt-sleeve environment, that would have been a failure.  Oh, that's something that no other current spacecraft can do (other than the ISS, of course).

Tellingly, the U.S. space program is abandoning spaceplanes and going back to Apollo-style rockets. The Russians have always relied on cheaper and more reliable disposable rockets; China plans to do the same.

My personal view (which I don't present as fact, unlike Amos) is that going back to a capsule design is a step backwards; it is a demonstration of uncreative simple-mindedness and lack of vision.  Have we abandoned the quest for innovation that drives us to do more than just copying others?

According to reports after the Challenger disaster, the ship exploded because of a faulty joint that included an O-ring hardened by especially cold conditions before launch.

Actually (I'm being pedantic here) the "ship" didn't explode.

More importantly, this was far from an isolated problem, as illustrated by a report by Richard Feynman. Feynman slammed not only the O-ring error but the entire process of building and testing the shuttle, plus the management style and decision-making of NASA, for good measure.

Anyone who claims to speak authoritatively about the Challenger disaster should read Diane Vaughan's The Challenger Launch Decision.  In it we learn that the Feynman's frequently-quoted conclusions were coached, based on incomplete information, and not really fair.  Amos goes on to quote reliability statistics, which is always a fool's errand (and, by his own argument, not the "tests that matter").

So it was clear, as far back as 1986, that the shuttle was an objective failure judged by its own goals.

No, the Shuttle program was a failure judged by your standards.  Let's keep that straight.

The shuttle also failed a more basic, primal test: it's just not that cool.

This is clearly a subjective argument, but I completely disagree here and I would guess that most school children would as well.  How would you compare the "coolness" of the Shuttle to that of a capsule, which crams its occupants into a tiny, undignified box while orbiting the planet in boring stillness?  What of the graceful acrobatics of the Orbiter in space, and its gliding return?  The Shuttle's remote manipulator is pretty cool as well.  Soyuz capsules are fitted with a firearm so that returning crews can defend themselves against bears after untangling themselves from its parachutes.  How is that cooler?  He points out that the purpose of putting humans into space is to explore.  While the Orbiter could not leave Earth orbit, it does enable exploration by means of probes and telescopes.  It allowed us to explore Earth as well, by creating (at the time) the most accurate and detailed maps of the Earth's surface to date.  It enabled the creation of the ISS, which serves as a learning platform so that we can learn how to design missions and hardware suitable for long-term crewed missions (I'm sure Amos feels this is a waste too).

Ask anybody who was never tempted to go to Space Camp what the shuttle's accomplished since fixing the Hubble in 1993.

Willful ignorance does not make a convincing argument.

Perhaps worst of all, the shuttle not only failed its own mission but prevented NASA from doing much else.

Politics and money prevented NASA from doing much else.  The Shuttle program was expensive, but a significant portion of the expense was the waste inherent in any government program.  NASA could have used the Shuttle's capabilities to construct and launch a true spacecraft (one that stays in space) for planetary exploration.  They didn't.  That is a failure, but it's a failure of NASA and the public (as Amos alludes to in the beginning) - not of the Shuttle program.

Instead, we'll have to bum rides on the old, cheap, and dependable Russian Soyuz, which is galling not only because it highlights what a flop the shuttle was, but also because the space program still has an anachronistic whiff of the Cold War about it.

The Soyuz program may be "old" but the Soyuz craft have undergone several major revisions.  More than the Shuttle program, but that's because the Soviet and post-Soviet governments have cared to spend resources to improve it.  As for "dependable" - shall I bring up statistics again?  Maybe you could do a little basic research before you call the Soyuz program dependable.

OK, so Amos has clearly constructed an opinion piece, and everyone is entitled to their opinions (even ill-informed ones).  But it's extremely disappointing to see such a poorly researched, one-sided essay posted on Discover.  We should always welcome dissenting opinions and consider all rational arguments, but this sort of essay does not belong in a publication aimed at an intelligent audience.