Fat Steve's Blatherings

Wednesday, October 06, 2004

Pop Quiz

      What are the most signifigant aviation and space dates in the last hundred one years?

12/17/1903: Orville Wright becomes the first human
                      being to make a powered flight.

07/25/1909: Louis Blériot flies the English Channel.

05/16/1919: NC-4 takes off from Trepassey Bay,
                      Canada, on the first trans-atlantic
                      flight, crew Lt. Commander Albert
                      Read, Lt. jg. Walter Hinton, Lt.
                      Elmer F. Stone, Lt. James L.
                      Breese, Ens. Herbert C. Rodd, Chf.
                      Machinist's Mate Eugene S. Rhoads.

05/27/1919: NC-4 reaches Portugal, finishing first                        trans-atlantic flight.

05/19/1927: Charles Lindbergh flies New York
                       to Paris, nonstop.

10/04/1957: The Soviet Union launches Sputnik,
                       the first artificial satellite.

11/03/1957: The Soviet Union launches Sputnik-
                      2, carrying the dog Laika, the first
                      living creature to visit outer space.

04/12/1961: Yuri Gagarin becomes the first
                      human being to travel in space, and
                      the first to return safely.

07/21/1969: Neil Armstrong and Buzz Aldrin
                       land on the moon.

04/12/1981: Space Shuttle Columbia
                      makes its first orbital flight.

09/29/2004: SpaceShipOne makes
                        its first X-Prize flight.

10/04/2004: SpaceShipOne makes
                        its second X-Prize flight, winning
                        the competition.

      The aircraft flights listed above were stunts.  None accomplished anything important in itself.  But together they led to a great thing, today's long-range, cheap air travel industry.

      The space launches of the 1950s and '60s were stunts too.  Did these stunts lead anywhere useful?

      Sputnik did.  Kudos to the Soviet Union, now gone.  Sputnik made possible the entire present commercial satellite business, saving lives through weather satellites, bouncing radio and tv signals live around the globe, guiding planes and bombs with the global positioning system.  But the manned space flights led nowhere.

      The reason is not, as many say, that manned space flight is inherently useless.  The repair of the Hubble Space telescope turned a potential total fiasco into a slightly qualified success.  Arthur C. Clarke once pointed out, in a book on space travel whose title I've forgotten, that another expensive satellite once failed, totally, when it was quite possible that a man with a screw driver could have fixed it.

      The Soviet and U.S. manned space programs went nowhere because they weren't devised for high-volume activities.  As Rand Simberg recently wrote, the key to low cost is high activity:
Back in the 1980s and early 1990s, as an employee of a major government aerospace contractor, I participated in and managed several studies relating to future launch systems. . . .

As we looked at all the combinations of architectures and models, we discovered something interesting. While some vehicle design concepts were clearly better than others, they were all extremely expensive per-flight for the low-activity scenarios, and they were all much less expensive for the high-activity scenarios. . . . The cost per-flight or cost per-pound varied dramatically — in some cases by a factor of ten — depending on the level of activity for a given vehicle in each mission model.

This means that even the theoretically best vehicle concept, if flown rarely, will be unaffordable to fly. A mediocre design, flown often, will beat it in cost per flight. How frequently we used the hypothetical launch system was much more important than what kind of propellant it used, or how many stages it had, or whether it took off or landed horizontally or vertically, or any other design choice. This, to me, was the key insight from all of those studies, and it’s one that remains true to this day. For example, the costs associated with the space shuttle largely go to pay the army of personnel and associated infrastructure needed to keep the shuttle fleet operational at all, even when the shuttles don’t fly. This doesn’t mean, of course, that we should ignore vehicle design, but it does mean that we need to pay much more attention to the dynamics of the market.

The reason for this is obvious, in retrospect. Consider the following example, for which I’ll use some simplified but reasonable figures. Imagine that Boeing spent $10 billion to develop the 747 — but instead of building hundreds and flying each of them daily (as is the case), they only built five and flew each one only once per year. Let’s say that Boeing didn’t make any profit, but sold the five airplanes to American Airlines for $2 billion apiece. Assuming that American Airlines can borrow money at less than ten percent interest, it has annual costs in aircraft payments of roughly $200 million per year for each airplane. Even if they had absolutely no other expenses (fuel, pilots, flight attendants, marketing, ticket agents, etc.), and if each aircraft had 400 seats, the airline would have to charge half a million dollars per ticket just to cover the loan for the aircraft purchase. [my emphasis]

      The Space Shuttle was supposed to be a high volume space transport, flying up to fifty flights per year.  Instead, it averaged five, and peaked at nine.  One estimate of shuttle costs says:
The shuttle program inherited from Apollo huge fixed costs - the Manned Spaceflight Center in Houston, the cadres of government and contractor workers at the Kennedy Space Center, and so on. The result was that there is a fixed base cost of around $ 2.8 billion per year, just to keep all those people and facilities in place, even if you don’t conduct any flights at all (as occurred after the shuttle disaster). The marginal cost of each flight added to this base is under $ 100 million per year. Seen this way the shuttle is almost competitive expendable boosters - but doesn’t come anywhere near the reductions NASA promised when development started. But if you divide the usual number of flights per year by the total costs, you come up with a figure of $ 245 million per year, significantly more than a Titan 4 or Proton launch with the same payload.

      And that estimate assumes twenty flights per year.  The reality of five is more like $660 million per flight.

      But the White Knight carrier vehicle and SpaceShipOne are totally reusable, and able to go into space with a turn around time of five days.  Sir Richard Branson is talking about a fleet of five.  That means maybe 300 flights per year.  Once we get that kind of turn around on an orbiter, cheap space flight will be here.  Space colonization will follow.

      And leaving the planet permanently will be perhaps the most signifigant event in the history of the human race.

      Finally, we're on our way.  Now, let's start funding X-prize Two, $100,000,000.00 (One Hundred Million) for the first completely re-usable eight person orbiter to fly twice in two weeks.



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