BFR News

Among other things, its fins are growing. This happened with X-33, too. Hope BFR has a better fate.

In terms of the passenger announcement, it’s worth noting how different this trip will be from Apollo 8 (whose fiftieth anniversary comes in December), in terms of how spacious the accommodations will be. This is not your grandfather’s moon voyage.

[Update a while later]

Tim Fernholz has some questions. I have one for him: What does “certifying the Falcon Heavy to carry people” mean? Or look like?

[Update late morning]

Scott Manley analyzes.

18 thoughts on “BFR News”

  1. Eric Berger also has some questions.

    Give the very similar titles, I first wondered if they were the same article, but they are quite different. The one question I thought was most missing from Berger’s article was Fernholz’s third question, namely, “Why is SpaceX talking about this now?” I hope we get a better sense of this on Monday, and the answer might be that the customer either wanted to go public with it or was sure that it would leak once he finalized the deal. Gwynne Shotwell has been talking recently about an upcoming space tourism announcement, and Yusaku Maezawa (2017 worth $3.6B per Forbes) back at the beginning of the month tweeted that he would be making a big announcement mid September, and a lot of his followers suspect that he is the customer.

  2. When I saw the Space-X illustration, I thought at first it was from the Onion. What? A moon-based spacecraft bearing wings and a tail fin?

    1. My understanding is the spacecraft is question isn’t designed primarily to go to the moon, but to got to Mars and return to Earth, aerobreaking at both ends. Though a trip to the Moon and back shouldn’t be a problem for it. With the concentration of mass represented by the engines, that tends to mean large fins or tail first aerobreaking.

  3. Fins, number of engines, vertical vs horizontal landing, and what the ablative heat shield is are all great things for nerdy nerds to worry about. I want to know how many seats the different variants will have, how many support launches are needed for each destination, and what the price per launch is.

  4. “Real Soon Now©®™” is what I keep hearing. Not yet, but real soon now…

    Wait, just a bit longer…

    I’m old enough to remember when Space Adventures announced their first passenger for a round-the-Moon trip. I’m getting to the point where I’m disinterested in promises, and interested in results. I will grant that SpaceX has delivered more results than most. But the industry needs to get its act together and start accomplishing more than PDRs and big promises.

  5. It’s a good question to ask, “what do you mean by certification”. But I read it as SpaceX has no plans to study BFR in relations to humans riding on it. So long as it is capable of only making a dent in the ocean if it fails; that’s good enough for unmanned safety. I wouldn’t put humans on BFR anyway. Let it launch the large structural pieces, and transfer humans on smaller vehicles. We don’t make freight trains and cargo ship for passenger comfort, and other than tradition and maintenance; those vehicles don’t necessarily require onboard human operators.

      1. There has been some speculation about a possible role for Dragon/Falcon here – that perhaps SpaceX has it in mind, at least initially, to launch BFS to orbit unmanned, and once refueling is completed (or underway), SpaceX would launch crew/passengers up with Dragons, transferring them in orbit, so as to assure them the benefit of an LES (something which BFS cannot have).

        The problem with THAT is that it would take quite a number of Dragon flights, which in turn would undermine the cost effectiveness argument. Imagine you’re putting 80 people on board for a Mars flight. Well, a Dragon at max capacity is 7 people, and that would mean at least 12 Dragon flights to transfer them up.

      2. I see my idea of a mission plan isn’t what SpaceX is planning. I still think it doesn’t need to work that way, but it will need to be certified for humans if it will do what SpaceX is planning.

        1. certified for humans

          Again, what does that mean? This vehicle will cost millions of dollars; if it’s not reliable it will be unaffordable. Shuttle’s unreliability was why it had to be canceled. And if it’s reliable enough to provide mission assurance that they will have a low risk of vehicle loss, it’s reliable enough to carry humans on an informed-consent basis. There is currently no certifying authority for private passenger space launch.

          1. Even without a governmental certifying authority; someone would have to determine, regardless of reliability, how many passengers could be aboard and for how long. Right now, it seems there is no plans to provide any assurance for even 1 person. The Shuttle was certified to carry up to 8 passengers for 2 weeks. SpaceX will need some number of passengers for something like 1.5 years. Who does that certification may not be known; but someone will need somebody with some assurance that the vehicle has equipment and reliability to support X human life for Y amount of time in space.

        2. In a rational world (ha ha) the ability to relaunch several times without major rework goes a long ways towards certification as a safe launcher. Add in a system to quickly detect yield and stress fractures in the structure and you should get plenty of warning of the big failures.

  6. I sincerely hope that’s just an “artist’s concept” illustration, because aerodynamically, it has real problems if there’s a desire for a lifting entry (and if not, why have fins at all?). They are essentially the same as the X-33’s problem. In a lifting body, you need the forebody to be negatively cambered (slope up from body to nose), so that it generates a “nose up” pitching moment on the body. You then counter that with a “tail up” pitching moment with the fins. All of this is lift generating and that’s why you can get decent L/D out of a lifting body.

    The illustrated vehicle has a downward slope on the nose, which makes a “nose down” moment, which has to be countered by a “tail down” moment from the fins, all of which subtract lift. And in a vehicle with small lifting surfaces, you don’t have that much to spare.

    1. Jeff, I suspect this is not the last illustration of BFS we will see before it’s all said and done. Your points are excellent. I think there will be more to come here, probably along the “lines” you make.

      One of the issues I think will be interesting for those with roving camera will be to see if “grasshopper” style tests will be conducted with BFS out in Texas or perhaps over water from Boca Chica. First uncrewed and then crewed. Seems like FAA at least would be the single point of reference for grasshopper flights within the atmosphere and that gives SpaceX and single authority to look for whatever waivers etc are needed for “experiment aircraft” for which rules are already on the books.

    2. It’s definitely just an artist’s concept. Why fire the engines in that location?

      I see that there’s some sort of canard on the nose, perhaps to counteract that nose down moment.

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