NASA might scale down the first manned SLS flight

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In order to meet its present schedule and budget, NASA is considering scaling down its first manned SLS flight in 2023 by using the same smaller version of SLS that will fly the first unmanned test flight in 2020.

The SLS has been in development for the last decade, and when complete, it will be NASA’s main rocket for taking astronauts to the Moon and Mars. NASA has long planned to debut the SLS with two crucial test missions. The first flight, called EM-1, will be uncrewed, and it will send the smallest planned version of the rocket on a three-week long trip around the Moon. Three years later, NASA plans to launch a bigger, more powerful version of the rocket around the Moon with a two-person crew — a mission called EM-2.

But now, NASA may delay that rocket upgrade and fly the same small version of the SLS for the crewed flight instead. If that happens, NASA would need to come up with a different type of mission for the crew to do since they won’t be riding on the more powerful version of the vehicle. “If EM-2 flies that way, we would have to change the mission profile because we can’t do what we could do if we had the [larger SLS],” Robert Lightfoot, NASA’s acting administrator, said during a Congressional hearing yesterday.

NASA clarified that astronauts would still fly around the Moon on the second flight. However, the rocket would not be able to carry extra science payloads as NASA had originally planned. “The primary objective for EM-2 is to demonstrate critical functions with crew aboard, including mission planning, system performance, crew interfaces, and navigation and guidance in deep space, which can be accomplished on a Block 1 SLS,” a NASA spokesperson said in a statement to The Verge.

The problem here really is that Congress keeps throwing money at this boondoggle. It will fly, but it will never be able to make the exploration and colonization of the solar system possible. It is simply too expensive and has a far too slow launch rate. Instead, it will allow for NASA to do stunts in space, while elected officials can preen and prance about, bragging about the jobs they brought to their districts.

And the nation’s debt will grow, and grow, and grow.

I hold to my prediction that private companies will bypass SLS in the 2020s, doing far more for far less. The differences between them will become downright embarrassing to SLS and Congress.



  • Localfluff

    A Falcon Heavy with crew separately launched by an F9, both reused, would put about as much mass in orbit as SLS Block I can do. NASA has contracted the first crewed Dragon flight for $133 million. With a cargo FH that makes $223 million. With a second FH launch, a real crewed Lunar surface mission could be launched for $313 million for the shipping. Or rather $388 million with a Ba330 for 60 days for $75 million (according to Bigelow in 2014) during the transfers and parked in Lunar and Earth orbit. Then one needs a Lunar lander and an ascent vehicle and surface exploration equipment. A third FH cargo launch would be very helpful, if one want to be ambitious to bring a Ba330 along, the shipping bill still stays below $500 million, or about half to a quarter of what a single SLS+Orion launch around the Moon. And SpaceX aims for a launch cadence that could supply multiple such missions a year.

    SLS block II still has all of the rocket engine developments ahead of it, which often is the hardest part in spaceflight. Thus far they have only refurbished existing Shuttle engines in storage. The upper stage engine will be evolved from an established one, but already its dimensions are much different making me suspect that it is an ambitious development project. And the “advanced” solid boosters remain to be developed or evolved. SLS Block II maybe will cost as much to develop as SLS Block I did, tens of billions, and take as long, tens of years.

    When ISS is deorbited in 2024, NASA would not launch a single astronaut for 10 years. Then they would, every third year, make one launch of the small Orion capsule to nowhere for a couple of weeks, using a couple of launches for robotic missions. That is how it would be if it hadn’t been for private space.

  • Diane Wilson

    Assuming that it’s possible for Congress to be embarrassed.

  • Orion314

    SLS will never lift off , no reason to think it ever will, their is no mandate for it to ever fly. it is just a jobs program. Results are not required.

  • Richard M

    “SLS block II still has all of the rocket engine developments ahead of it, which often is the hardest part in spaceflight.”

    A sad reminder of just how hardware poor this program is.

  • Max

    Localfluff Said;
    “Then one needs a Lunar lander and an ascent vehicle and surface exploration equipment. A third FH cargo launch would be very helpful, if one want to be ambitious to bring a Ba330 along, the shipping bill still stays below $500 million, or about half to a quarter of what a single SLS+Orion launch around the Moon.”

    I am sure Elon musk would donate that third FH rocket if he can include a Tesla model X SUV for the astronaut rover vehicle.
    Along with the supplies, and a Ba330 Bigelow moon camping tent, he could throw in an extra battery pack and solar charging station.
    The SUV Will be stripped down and loaded with scientific equipment for driverless exploration after the astronauts leave but can be launched with a light weight fake body for photo op. A video of the SUV climbing a crater wall then driving around the interior at high speeds to show off for example.
    The feed would be live on every television in the world, the advertisements alone would make up for the cost of the adventure.
    The Lunar lander and ascent vehicle is the only tricky part that will hold up the mission. NASA will will drag its feet till the very end.
    Landing FH rocket on the moon will present a new challenge without a pad. I would suggest two pointed long rods of spring steel that will sink 5 to 10 feet into the soft lunar soil with the weight of the payload and the second stage.
    Once stabbed into the dirt, and being offset to one side, the rocket will tip over slowly with the assist of positioning jets. This will allow easy access to the payload at ground level. The rocket will not be able to be used again, not even in an emergency… But we have other uses for the left over fuel if the astronauts plan on staying for 60 days.
    The shadow of the rocket will provide protection from radiation. The rocket fuel (hydrogen/oxygen) will provide battery/rover re-charge energy, heat, water, extra 02 to breathe. All the comforts of home.
    If they get too hot, I would suggest a overhead umbrella.
    If the cargo hold garage door can be made air tight, it can work as a back up living space to the Bigelow tent. The life support can be designed to be modular.
    The same is true of the hydrogen tank, it could be constructed with an air lock built in. That would come in handy if a large solar storm was to occur. Vent the excess hydrogen and climb in.
    I imagine Elon musk will insist on his own Space X launch Crew to take over the duties of the driverless X class Tesla/lunar rover since he funded the project.
    He could rename it “Tesla prospector” as it goes out exploring, sampling, site seeing with live feed on his website. Universities can provide gas spectrum analyzer’s, magnetometers, and dozens of other Syfy equipment… maybe even a core sample drill rig to take advantage of the vehicles weight. The possibilities makes your head spin.
    We can’t forget the possible lava tubes. A camera on extended boom may not be enough. A rocket drone will have to be developed that can last more than a few minutes in the airless environment with battery powered lights and camera.
    Come on Elon, leave NASA in the dust.

  • mkent

    Hmmm. I thought NASA Watch’s latest post on SLS would be the talk of the town.

  • mkent: Those are twitter posts. I generally pay very little attention to the junk on twitter.

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