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Elon Musk gives another tour of Starbase

Tim Dodd of Everyday Astronaut has posted another 44 minute long interview with Elon Musk that took place as Musk gave him a recent tour at Boca Chica, walking around the base of the Starship and Superheavy boosters being prepared for that first orbital launch.

I have embedded the interview below. It has the following interesting take-aways:

  • In describing their decision to eliminate completely a separate attitude thrust system for Starship and instead use the fuels in the main tanks using controllable vents, Musk once again demonstrated his engineering philosophy that “the best part is no part.”
  • The company is definitely planning to test the deployment of some Starlink satellites on that first orbital test flight.
  • Musk once again emphasized that there is a high expectation that this first orbital flight will fail, but they are unbothered by this because this first ship is considered a prototype anyway that must be redesigned. Whether it completes its flight or not, the flight will tell them what needs to be done for future iterations.
  • They are aiming with Starship to reduce to cost to bring a ton to the surface of Mars from $1 billion to $100K. Musk called this improvement “insane” but entirely possible.
  • Musk also noted how the design of Starship is not like a plane, which wants to develop lift. Starship instead is designed to fall, but do so as “draggy” as possible. The goal is to shed as much velocity as possible, as soon as possible.

Dodd also notes this video is the first of a new series.

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On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

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  • Ray Van Dune

    I think another big takeaway is the one I mentioned the other day – that the SS will accelerate off the launch table quite briskly, since counterintuitively the most efficient manner in which to utilize the propellant of a fully-reusable rocket is to have a high thrust/weight ratio.

  • Rod

    In his desire for system economy, I would think that a mission plan would involve launch, deliver payload, and land. The more time that your vehicle is hanging around in orbit, is time that it is not back on the ground being prepped for the next launch. Which brings me to the “draggy” statement. A vehicle that can return rather quickly will need some lift to take landing cross range into account. Otherwise, the orbiter will spend some time in orbit waiting for one’s ground track to cross the launch site. I wonder how they traded that requirement.

  • Ray Van Dune

    Rod, I have been unsuccessful in finding out what the cross-range capability of the StarShip is, but it can’t be much, compared to the Shuttle, can it? And as I recall reading, the Shuttle design was just barely capable of re-landing at the launch site after a single orbit, although this maneuver was never performed.

    So for the StarShip to re-land at the launch site, you could assume it would require about 1/2 of a full orbital cycle or 1/2 * 360/22.5 deg * 90/60 min, or 12 hours covering 8 orbits. Thus if it launched to the SE at 0600 hrs, it would approach and land from the SW at 1800 hrs.

    I think actually you have to add 45 minutes, or 1/2 orbit to the total time, because it launches on one side of the Earth and lands when the launch site has moved on the opposite side.

    But the bottom line is that a one or two orbit mission doesn’t seem possible, if a mission begins and ends in the same place! Am I mis-analyzing this?

  • GaryMike

    I am enjoying Tim Dodd’s unexpected, unplanned journey to the center of the SpaceX Universe.

    I think that Mr. Musk rather enjoys it, too.

  • Jeff Wright

    He may regret not having that separate thrust capability. I might want jets for landing.

  • Rod

    Ray Van Dune, I must say that the original shuttle requirement that it launch from Vandenberg fly once around and land at Vandenberg was crazy. The shuttle was filled with bizarre requirements. And, I truly believe that one of Mr. Musk’s powerful advantages is that he can rewrite the requirements when he so chooses. Consider Starship, if it was a government program, any change in requirements–like composite to steel–would take a year or two of conferences and committees just to get it on the agenda. Elon just says: “Make it so!”

    However, cross range turned out to be important for the shuttle. I remember many landings where they decided just minutes before de-orbit burn that the weather was bad. They said that they would wait one orbit. You can do that with cross range. If Mr. Musk’s vehicle lacks cross range they would have to wait a day for bad weather. Perhaps, the extra site a Canaveral will add to flexibility.

  • Rod: I suspect that because Starship lands vertically, on its engines, rather than gliding in on a runway, like the shuttle, it has a lot more flexibility concerning the weather, thus reducing this issue significantly.

  • Ray Van Dune

    I read the comments Rod and Bob with interest, but I am not sure they address the question of whether the Starship will be able to perform a “quickie” one or two orbit deployment of a payload and return to base. I am not sure my assumptions are correct, but they seem to indicate that the answer is “no”.

    If so, what impact this will have on operational use is debatable, but at least it will probably:
    1. Limit the missions to one per day.
    2. Reduce the payload by virtue of increased propellant boil-off measures.

    I remember how cost-sensitive Elon has proclaimed himself to be: he says the only real measure of effectiveness of a Mars ship design is the cost per effective ton, delivered to the surface of the planet! Applying such rigor to evaluating a LEO deployment design, there is a huge difference between the potential effectiveness of Starship, and that of a design that can do a “quickie”!

  • Rod

    I believe that the shuttle’s weather constraint was rain. The tiles and carbon carbon leading edges did not want to impact raindrops at Mach 1. We found out with Columbia just how brittle the leading edges were. I don’t know the toughness of the second generation tiles currently being affixed to Starship.

  • Steve Richter

    Shouldn’t the interviewer disclose the ground rules for this interview? There must be questions Elon says he does not want to answer. Like anything FAA approval process related. Has he had contact with the democrat party leadership? As in messages from intermediaries he has received where they outline what Biden and Pelosi want from him. Could someone ask him why the Boca site was chosen to be the SpaceX space port? Maybe Elon could make a great case for why it is a great location. Why does SpaceX not have a public relations team making the case for why the FAA should grant approval to launch Starship into orbit?

  • Concerned

    Ray van Dune:: your analysis is a good one, but inclination does make a difference. In fact, a once around trip is quite feasible and has a bunch of other advantages for equatorial orbits. See Rand Simberg, “Earth’s Natural Harbor” at

  • Edward

    I also liked the information about various differences in the hardware. It shows that they have been iterating even without flight experience, such as a “Pez dispenser” method of releasing smaller payloads rather than the clam-shell concept shown in early depictions of missions. Once SpaceX is allowed to fly Starship to orbit, they should gain better knowledge of the reality of the system.

    Rod noted: “A vehicle that can return rather quickly will need some lift to take landing cross range into account. Otherwise, the orbiter will spend some time in orbit waiting for one’s ground track to cross the launch site. I wonder how they traded that requirement.

    Around 41 minutes into the video Musk said that, unlike an aircraft, Starship needed drag rather than lift capability during reentry, but there will be some need for guiding Starship to the landing site, and this will require some amount of lift to provide the ability to guide Starship some amount of distance farther, shorter, left, or right in order to fall downward onto the landing zone. This lift may help with this cross range capability on an easterly launch, where a single orbit mission would need to go about 1,500 miles further on or turn to only go a couple hundred miles north of the orbital track. A launch that goes to the north or south of due-east would complicate the cross range requirement for a Starship orbiter single-orbit return to launch site. For a polar launch, they may have to wait the 12 hours for the launch site to come around again, plus or minus the 45-ish minutes for the half-orbit that Rod mentioned, but that will also require some amount of cross range ability.

    Another factor not yet mentioned is the requirement that non-ablative heat shields must remain above a certain altitude (in a region of lower density air) during a majority of reentry, otherwise they overheat the heat shield and it ablates and is not reusable. This requires some amount of lift in order to remain high enough in the atmosphere until the ship is slow enough to not overheat the heat shield in the denser atmosphere. This is a link to an altitude vs velocity graph:
    Please note that by remaining above the thick line, a thermal protection system (TPS) can be reusable, but by dipping below that line the TPS becomes ablative and is not reusable. The Space Shuttle stayed above the line, but Apollo went below it.

    The Space Shuttle had a large excess lift capability, due to the single-orbit polar-mission requirement, so by design it had to make “S” turns during reentry. Starship presumably will require much less lift capability during reentry.

    Here is an 18 minute video as a primer for this discussion, “How to Land the Space Shuttle”
    Please note that although the Space Shuttle could not just increase its angle of attack, Starship can. By design. Bret also skipped the part where the Space Shuttle must remain high in the atmosphere until it is slow enough to safely descend into the thicker air.

    Single orbit missions may be desirable mostly for delivering payloads to orbit but it may not be possible to refuel a Starship in a single orbit. Tankers may not need a single orbit requirement, as it may take far too much time to dock and transfer the propellants.

    SpaceX may not be worrying too much about cross range capability at this point, but they may home in on these requirements as they get closer to operational status. I would not be surprised if SpaceX continues to iterate for a few years or a decade after becoming operational, and I would also not be surprised if they switched back to composite Starships after they have finalized their designs.

  • Cotour

    At this point you begin to realize:

    “Elon Musk Announces He Will Vote Republican For the First Time Ever After Years of Voting Democrat”

    Elon Musk is both John Galt AND Tony Stark.

    And then you wonder:

    Q: Has Elon Musk been so heavily invested in and developing electrics and how “Clean” and “Good” for the environment electric autos and solar is in pursuit of counter balancing carbon foot print carbon credit goodie points because his rockets which he intends to launch hundreds of in their regular operation? Thats a lot of carbon being introduced into the atmosphere.

    Is he that far ahead in this game? Is that possible?

  • Ray Van Dune

    I have been assuming that no refueling would be required (or possible) in a “quickie” single orbit deployment mission. Careful orbital insertion might allow a Starship to use a modest amount of maneuvering thrust to engage the upper atmosphere post-payload deployment.

    Then the question becomes does it have a sufficient lift/drag ratio to stay high to minimize heat shield ablation, AND to make the cross-range corrections required for single-orbit return to launch site?

    My glider-pilot gut says “no”. Elon?

  • Edward

    Ray Van Dune,
    You wrote: “I have been assuming that no refueling would be required (or possible) in a “quickie” single orbit deployment mission.

    Most of the deployments that we watch on Falcon 9 launch videos seem to happen shortly after launch, but I have seen a few that were many minutes, even close to an hour later. For these latter cases, a single orbit deployment may not work, but we cannot expect all mission profiles to be quick up-and-back missions. For those that can be, SpaceX could certainly design a Starship that can handle the cross range requirements. Right now they are just trying to get the thing to work, and future designs are probably just ideas or plans on drawing boards or in PowerPoint view foils.

    A tug already in orbit, or Starship carrying a tug, could take a payload to Geostationary Transfer Orbit, Translunar orbit, or escape velocity to another solar system destination. This way, Starship would not need refueling (did Musk call it something like “retanking?”) on orbit and could eject the payload early enough for a single orbit deployment mission and return to launch site an hour and a half after launch.

    Have I mentioned, yet, that I like the “Pez dispenser” concept?

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