Commercial Spaceflight: Another Step

Posted on March 8, 2019 by Brian H. Gill

The SpaceX Crew Dragon demonstration and test flight has gone well. The spacecraft returns to Earth Friday morning.

Folks may be riding Crew Dragon to and from the ISS later this year.

I found quite a bit about space stations, docking technology and other more-or-less-related topics. But if this is going to be done in time, that must wait until another day.

— Update, March 8, 2019 —

The Crew Dragon’s heat shield and parachutes worked. The capsule landed in the Atlantic, about 280 miles off the Florida coast:

Now, back to what I had ready yesterday.

Space Stations: Imagined and Real


(From NASA, via Wikimedia Commons, used w/o permission.)
(ESA astronaut Hans Schlegel, in the ISS Columbus module.)

“2001: A Space Odyssey” wasn’t spot-on accurate about early-21st century tech and space flight. In 20-20 hindsight, it’s easy enough to see that straight-line extrapolation of 1960s spaceflight progress wasn’t likely.

On the other hand, I think the assumptions were good enough for a movie. Although the scale of 2001’s orbital and lunar installations seems extravagant.1

We’ve had about a dozen space stations launched during the last third of a century. Some didn’t stay up long enough to house a crew, one fell into the Pacific before reaching orbit, and all but one or two aren’t there any more. One became part of the ISS.

The International Space Station, ISS, has been in orbit and in use since 1998. Folks started staying there for extended periods in 2000.

Like Kubrick’s Station 5, it’s still being assembled. Apart from that, and having a shirtsleeve environment inside, it’s not much like its movie counterpart.

The ISS doesn’t have artificial gravity, accommodations don’t include a Hilton Hotel and it’s nowhere near as roomy. But much of the interior is white, like Kubrick’s Station 5.

Transportation services aren’t as apparently-affordable, either. From 1998 to 2011, each Space Shuttle launch to the ISS cost $450,000,000 to $1,500,000,000.

The Shuttle could carry 35,380 pounds to the ISS, $12,720 to $42,397 per pound. Today’s SpaceX Dragon costs are about the same, averaging $30,000 per pound on the same run.

I’m not sure how to compare that with commercial airline rates. Numbers I’ve seen for air transport expenses have been in cost per hour, not cost per trip.

Commercial Flights


(From Library of Congress Prints and Photographs Division/Andro96, via Wikimedia Commons, used w/o permission.)
(Airline service, the early years: DELAG’s L 7 zeppelin.)

I don’t know what sort of commercial flight schedule would make sense for service to and from low Earth orbit (LEO). That won’t stop me from guessing. And making some whacking great assumptions.

Something in LEO takes 128 minutes or less per orbit. Many satellites orbit every 90 minutes. Space Shuttle missions spent considerable time in orbit. It made sense, since the Shuttle sometimes doubled as a space station before returning to Earth.

That’d be like an airliner arriving at Macau International Airport on Monday and waiting there until Saturday before going to its next stop.

I suspect that commercial passenger and cargo service will operate more like air transport.

I’ll assume, reasonably or not, that a typical spaceline’s LEO round trip will take five hours. That’s 90 minutes travel, an hour in orbit and another on the ground.

I’ve read that flying an Airbus A380 costs $26,000 an hour. At five hours, that’s $130,000 — a small fraction of Shuttle and Dragon flight expenses.

It’s still a bargain, compared to using single-use launch vehicles.

I figure costs will go down, as tech improves spaceflights become more routine.

We didn’t get aircraft like the A380, after all, until nearly a century after DELAG’s first zeppelin started ferrying passengers between Frankfurt am Main and Düsseldorf.2

Crew Dragon visits the ISS


(From NASA, used w/o permission.)
(ISS staff inspecting the SpaceX Crew Dragon. They’re wearing protective suits to avoid dust, in case some got shaken loose during launch.)

“SpaceX Crew Dragon Hatch Opened after Successfully Docking to Station”
Anna Heiney, NASA Blogs (March 4, 2019)

“After making 18 orbits of Earth since its launch early Saturday morning, the Crew Dragon spacecraft successfully attached to the International Space Station’s Harmony module forward port via ‘soft capture’ Sunday, March 3….”

This week’s Crew Dragon flight carried 400 pounds of cargo to the ISS and will return with 300. But it’s mostly a test flight, with no passengers apart from “Ripley,” the test dummy.

Ripley’s sensors include a microphone to record what folks would hear during the flight. The idea is to tell SpaceX and NASA what someone would feel and hear.

Maybe a test pilot could give more nuanced observations, but I don’t see a point in taking the sort of risks that eventually killed Otto Lilienthal. (May 26, 2017)

That brings me to another difference between space travel as imagined in “2001” and what we have today. Kubrick’s shuttle and lunar lander were apparently so reliable that passengers and crew didn’t need spacesuits in transit.

We’re not there yet. My guess is that some sort of pressure suit will be standard apparel for takeoffs and landings for a long time, like fasting seat belts on today’s airliners.

The SpaceX spacesuit seems to be designed mostly as safety gear: “…each custom-tailored suit is meant to provide a pressurized environment for all crew members aboard Dragon in atypical situations such as cabin depressurization….” (Dragon, SpaceX)

Maybe SpaceX has found ways to make a pressurized spacesuit flexible and svelte. More likely, designers figure that even in an emergency folks in the Crew Dragon won’t need to move much.

There’s a single control panel inside, but normally the spacecraft’s AI serves as pilot.3

Being Human

I’m pretty sure that airlines, space stations and reusable launch vehicles won’t solve all our problems. Neither will what we’re learning about this universe.

I’m also sure that seeking knowledge and developing new technology is part of being human. So is deciding how we use our knowledge and tools. (Catechism of the Catholic Church, 1723, 2292-2295)

I’ve talked about that sort of thing before:

1 In the movies:

2 A century of zeppelins and spaceships:

3 Commercial spaceflight, mostly SpaceX:

How interesting or useful was this post?

Click on a star to rate it!

Average rating 0 / 5. Vote count: 0

No votes so far! Be the first to rate this post.

I am sorry that this post was not useful for you!

Let me learn why!

How could I have made this more nearly worth your time?

About Brian H. Gill

I was born in 1951. I'm a husband, father and grandfather. One of the kids graduated from college in December, 2008, and is helping her husband run businesses and raise my granddaughter; another is a cartoonist and artist; #3 daughter is a writer; my son is developing a digital game with #3 and #1 daughters. I'm also a writer and artist.
This entry was posted in Science News and tagged , , , . Bookmark the permalink.

4 Responses to Commercial Spaceflight: Another Step

  1. Manny says:
    March 11, 2019 at 04:08

    Even if I got a free ride, I don’t think I would take a space ride. Yes, that Hidenburg blimp is what I would think of.

    Reply
    • Brian H. Gill says:
      March 11, 2019 at 04:40

      🙂 I see your point. The Hindenburg disaster, and maybe its newsreel coverage, may have ended public confidence in airships.

      No transportation tech is 100% safe, of course: riding a horse can be fatal, for example. That said, Earth-to-orbit flights are still quite new – it’s been only about a half-century since the first.

      It’ll likely be some time before they’re as safe as airline travel: which I don’t think will stop many folks from going up. We do, after all, seem to see driving to and from work every weekday as an acceptable risk. And that’s almost another topic.

      Reply
  2. irishbrigid says:
    December 17, 2020 at 00:49

    Thought you said the ISS has been in orbit since 1998: “From 1982 to 2011, each Space Shuttle launch to the ISS”

    Missing or wrong word: “Something in LEO takes 128 minutes or per orbit.”

    The Friendly Neighborhood Proofreader

    Reply

Thanks for taking time to comment!