Of Space Shuttles and Landing Systems

People keep asking me what I think about NASA’s Space Shuttle program coming to a close. Without fail, I unthinkingly answer, “Nothing. I don’t think much of it.” It’s true. I don’t really know all that much about the Space Shuttle. To be honest, I’ve never really found it all that exciting. (The image to the left depicts a 2010 launch of the Space Shuttle Discovery.)

I am inclined to think that the Shuttle is about as interesting as Simpsons writer David Mirkin suggests in his episode “Deep Space Homer”. After NASA notes a decline in TV ratings (no one is interested three different kinds of mathematician flying in space), Homer is selected to join NASA’s astronaut corps as a representative of the common man. His overall ineptitude manifests itself when he breaks the onboard ant farm with his head, causing fellow crew member Buzz Aldrin to exclaim: “You fool!  Now we may never know if ants can be trained to sort tiny screws in space!” As far as I can tell, this isn’t much of an exaggeration of what constitutes a Shuttle mission. Teaching ants to sort screws in space is not all that interesting, and certainly not useful (although perhaps applicable to watch construction and, by extension, watch repair).

The history of spaceflight that I’ve spent years studying centers on the Space Race – from about 1945 (I include early jet aircraft as the precursor to spaceflight) to 1975, the year of the Apollo-Soyuz Test Program. What grabs me about this period that I don’t find as interesting in modern manned spaceflight is the technology. When President Kennedy picked the moon as the finish line in the Space Race in 1961, he did so because neither the Americans nor the Soviets had the necessary technology readily available.  Both had the long term potential to get there, but for all intents and purposes neither was ahead of the other. It put the two countries on equal footing.

The way both the Americans and the Soviets determined and approached the problems associated with a manned lunar landing are fascinating. (Admittedly I know a lot more about the American program than the Soviet since I haven’t yet taken on the task of learning to read Russian; I have only found a handful of sources in English about the Russian program.) Within the many technological aspects of the Space Race is the relationship between the astronaut and his spacecraft. On the American side, the Mercury, Gemini, and Apollo programs required human control, even if it was primarily in the name of political gain and national prestige.

The Mercury spacecraft allowed for minimal control by the astronaut; he could move the spacecraft around its axes of pitch, yaw, and roll but could not affect its orbit. The Gemini and Apollo spacecrafts were more sophisticated and offered the potential for a significant amount of pilot control. The relationship between men and machines in this era becomes a malleable one, and that’s where my interest currently lies.

The astronauts could take full control of their spacecraft by overriding the automated system, such as Neil Armstrong’s manual landing in the Sea of Tranquility or the extreme case of the Apollo 13 astronauts flying their spacecraft with its automated systems completely shut down. The astronauts could re-teach their computer by adjusting its programming, a necessary step taken by the Gemini 8 astronauts Dave Scott and Neil Armstrong when they entered new reentry data line by line to carry out a safe emergency reentry. Or the astronauts could do nothing at all and let the automated system (care of the engineers) control the mission.

The one area where this isn’t the case – where the man-machine reaction is largely unchangeable – is in the landing phase. During the Space Race era, once the reentry phase began there was little for the astronaut to do. The Gemini capsule was aerodynamically designed to include a limited lift capacity during reentry in the interest of achieving pinpoint landings, but any change the astronaut could bring about was minimal. The Space Shuttle, on the other hand, allows the astronaut to take full control of the landing phase. It is the first spacecraft within NASA to allow for pilot-controlled landings.

The history of landing methods, particularly the history of land-landing systems, has dominated my research for the better part of the past year and will continue to do so – as the topic of my master’s thesis, it is an ongoing project as I begin reworking my paper into a book. In the story of land-landing methods at NASA, the Shuttle is the natural ending point.

Depending on where you start your history, spacecraft landing methods come full circle. Since I typically begin with jet aircraft, this is the case.

In the 1950s, when NASA was the NACA (in a manner of speaking) and no one knew what a Sputnik was, the US Air Force was in line to dominate America’s future in Space with the X-15. This was the latest aircraft in the X-series that had previously spawned Chuck Yeager’s sound-barrier-breaking X-1. Launched from under the wing of a converted B-52 bomber, the X-15 flew in a parabolic arc, treating the pilot to a weightless few minutes at the apex before he began his descent. The X-15 landed on skids (which slowed the aircraft faster than wheels could) on the dry lakebed at Edwards Air Force Base in the Californian Desert. The aircraft broke speed and altitude records left right and centre. In 1963, pilot Joe Walker set the altitude record at nearly 66 miles, well past the 50 mile mark at which the atmosphere is sufficiently thin that space is said to begin. While too small to reach altitude and speeds required for orbit, later generations of the X-15, particularly the X-20, was shaping up to be the first space plane flown entirely by the pilot right down to its landing on a runway. (The preceding picture on the right depicts the X-15 during its landing phase. Clearly seen are its landing skids. For scale, the X-15 measures just over 50 feet in length and has a wingspan of just over 22 feet.)

But once NASA was incepted and tasked with getting a man in space as soon as possible, space planes took a backseat. Capsules such as the Mercury spacecraft were comparatively easier to launch into orbit and the splashdown landing greatly simplified the reentry phase as well as the capsule’s overall design. It didn’t need to be aerodynamically sounds to plunk into the Atlantic. With the second generation of manned spaceflight within NASA, project Gemini, there began a move away from splashdowns to land landings (for more about why land landings were favoured over splashdowns, see my previous post). NASA and various subcontractors went to great lengths to install a pilot-controlled land landing system into the Gemini spacecraft that would allow the pilots to land the spacecraft in like manner to an aircraft. They were entirely unsuccessful.

It wasn’t until NASA decided to designed an entirely new space vehicle rather than adjust an existing one that they achieved a land landing. The Space Shuttle was NASA’s first space vehicle to successfully undergo a pilot controlled landing on a runway. This is the one aspect of the Shuttle that I find really interesting, especially when compared with its predecessor programs. When NASA began testing the landing system of the Shuttle, it did so with gliding descent tests. Just like the Air Force did with the X-15, the Shuttle was released from a launch aircraft (the Shuttle Enterprise was launched from the top of a converted Boeing 747) and glided down to a landing on the dry lakebed at Edwards. Manned tests of the system followed the same pattern, again landing at Edwards. Full circle. (The image to the right depicts the Shuttle Enterprise as it separated from the Boeing launch vehicle. Late 1970s.)

A bit of a strange inconsistency emerges when looking at the Gemini and Apollo spacecrafts and the Shuttle side by side, particularly in terms of landing systems. The Space Race era is often considered by historians to be a golden age in manned spaceflight, when America had the audacity and budget to take on any challenge and achieved impressive technological feats. But the spacecrafts can be thought of as closed systems, opened to a certain degree to allow for astronaut control. The Shuttle era, on the other hand, is a utilitarian age; the Shuttle as its workhorse delivers far less payoff compared to launch costs.

The ‘golden age’ had the astronauts flying in a spacecraft that was largely a closed system. The Shuttle, on the other hand, allows for a significant amount of control, but lacks the caché and interest of its predecessor programs. The irony of the situation is that the Shuttle lands like an airplane in an era when test pilots are no longer the crème de la crème of astronaut candidates.

In light of the Shuttle’s interesting place in the history of landing methods and general man-machine interactions in the history of spaceflight, perhaps I ought to revise my answer to the previously posed question. What do I think about the Shuttle program coming to a close? Nothing, but let’s wait and see what NASA does next, how it lands, and maybe then I’ll devote a little more time to studying the Shuttle in terms of the progressing role of the man-machine relationship in spaceflight.

Suggested Reading/Selected Sources:

1. Godwin, R. X-15: the NASA mission reports, incorporating files from the USAF: Collector’s Guide Publishing. 2000.

2. Gordon, R. Michael. The Space Shuttle Program: How NASA Lost its Way. Jefferson: McFarland & Company Inc. 2008.

3. Harland, David M. How NASA Learned to Fly in Space. Burlington: Apogee Books. 2004.

4. Harland. The Story of the Space Shuttle. Chichester: Praxis. 2004.

5. Thompson, Milton O. At the edge of space: the X-15 flight program: Smithsonian Inst Pr. 1992.

6. Thompson, Milton O. Flying Without Wings: NASA lifting bodies and the birth of the space shuttle. Washington: Smithsonian Institution Press. 1999.

7. Tregaskis, Richard. X-15 Diary: The Story of America’s First Space Ship. Bison Books. 2004. (An excellent read!)

Comments

  1. says

    Amy! This is great!! I have a couple of comments to make on it in person, but the way you tell this story and all the detail you bring to it is fascinating.

    I’ve been ambivalent about the end of the shuttle program, myself. On the one hand, there’s much cooler technology being developed for the satellites and probes that we’re using to look at Earth and the rest of the Cosmos. But on the other hand, space flight is sexy science, and with the Constellation program floundering, there will be no American manned spaceflight. I wrote a blog on the subject a little while ago, though it’s not nearly as well researched and well thought at as yours.

    I have to start blogging again!! We can be blog buddies!

  2. Murgatroyd says

    What’s your opinion of Elon Musk’s plan for retrorockets on the Dragon capsule, for both escape and landing?

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