Monday, July 20, 2020

Using Starships a Habs on Mars

This is another one of those placeholder posts.  In this case, here's a little cartoon about how to modify and install Starship crew and cargo spacecraft as early living spaces on Mars.

Friday, June 19, 2020

If You're Still Thinking of Voting for Trump...

...then at least read this.

Can you really vote for somebody whose negligence caused at least 83,000 avoidable deaths?

Tuesday, June 16, 2020

You Need a Reusable Starship, But You Might Need an Expendable One Even More

Hans Koenigsmann says in an interview with Der Spiegel that SpaceX is still shooting for an orbital flight of Starship in 2020.  I'm not holding my breath on that one, but it did occur to me that maybe we've got the order of development for Starship all wrong.

If you assume that the first orbital test of Starship will be with a vehicle that's already done successful suborbital entry, descent, and landing, then the end of the year is going to be hard to make.  But what if the first Starships are expendable?  Indeed, what if expendable Starships are about as common as reusable ones?  Then maybe Koenigsmann isn't as crazy as he sounds.

What follows below is to some extent an update to the post I did last year about how to use Starship without subjecting crews to its risks during launch and EDL.  But there are some key differences.  First, we now know that SpaceX is part of the Human Landing System contracts, which means that NASA's going to use a variant of Starship (among other vendors) for the actual Moon landing.

More importantly, however, the economics change pretty radically if you allow for the possibility of expendable Starships and their close cousins, Starships that never return to Earth.

Saturday, June 6, 2020

The Police

I'm quite conservative when it comes to law-and-order.  Even as a not-completely-crazy libertarian, I believe that the freedom to make a life for yourself is enhanced if you have a somewhat neutral third party between you and people who'd like to prey upon you.  Policing, within well-defined limits (which do not included domestic military operations!!!!!), is essential.

But it's time to acknowledge that something has gone seriously wrong.

According to the Washington Post's database on police shootings in America, blacks are killed at a rate that's roughly 2.3 times that of whites.  By some other measures, the rate is nearly 5 times that of whites.  No matter how you measure it, something bad is happening.

There is plenty of anecdotal evidence that the deaths are only part of the problem, and that there's a pervasive pattern of harassment and humiliation that swamps the killings.  But we need to be careful here, because this is exactly the sort of situation where human beings' heuristics for drawing conclusions from small amounts of data can get us into trouble.  Unfortunately, there's very little data to be had.  That doesn't appear to be accidental¹, and it's suspicious enough to make us trust our anecdotal priors even more.  I'm going to accept the idea that the police are acting in a manner where at least the result is racist.

Why is this?

My white guy impression is that most police are decent people.  Decent people know that racism is bad, and likely don't self-identify as racists.  And yet, as a group, they're engaging in behaviors that are effectively racist.

Hypotheses for what's going on have to fall into one of two broad categories:
  1. There are a substantial number of police who are racist, whether they believe they are or not.
  2. Something about police organizations either requires or provides strong incentives for their members to engage in behaviors that have racist effects.
As a practical matter, there's not much to be done if hypothesis #1 is what's driving things.  We're not going to disband police forces.  Fewer things will dispel concerns about racism faster than widespread disorder.  Over the long haul, it'd be nice not to hire racist cops.  That seems like a worthwhile organizational goal, and one for which future cohorts of police should be screened.  But this is no solution for either the short or medium term.

So let's drill down on hypothesis #2, where something about the practice of policing causes racist outcomes.  Let's moot some behaviors that might lead to institutional racism:
  1. Police are taught how to be intimidating.  Unless you want almost as many cops as civilians, this is an occupational necessity.  Perhaps, however, the intimidation tool is relied upon too heavily.  I would think that that was a doctrinal thing that could be changed, although it's also a training thing, meaning that most good cops internalized the behavior back in the police academy.  Now that they're older, it'll be hard to retrain.
  2. Intimidation is easier if you're aggressive.  If aggression is necessary to succeed, then there's selection pressure in police forces to be aggressive.  Some aggressive people are thoughtful and careful to manage their aggression.  But a lot of them are just assholes.  Not necessarily racist assholes, but assholes nonetheless. As support for this hypothesis, note that spouses of police officers experience domestic violence at roughly four times the national rate.
  3. Police are taught to be very conservative when it comes to preserving their own lives and, even more important, the lives and well-being of their partners and fellow officers.  This is just Paramilitary Training 101.  But it leads to "Blue Wall" kinds of solidarity, which aren't necessarily in the public interest.
  4. Police are taught not to let people committing crimes get away.  It's hard to deter lawlessness unless its consequences are certain when it's observed.  This is a fine policy until somebody winds up getting shot while fleeing or beaten for resisting arrest.  After that, there's a lot of second-guessing.
  5. Police need an SOP to make hard decisions.  The trick to making as few bad decisions as possible is to rely on training and procedures whenever possible.
  6. There's a natural tendency to confuse bad areas with bad people.  Residents of high-crime areas lose the benefit of the doubt.
  7. Arms races between the cops and the criminals need to be won decisively by the cops.  In a society where guns bounce around like the particles in a gas, having better weapons and tactics is the only way to avoid getting killed.
All of these factors make perfect sense if your goal is to have an "effective" police force.  Perceived effectiveness is always important in government, because ineffectiveness makes the news, and news kills the careers of people it touches in most cases.

And we, the public, want an effective police force.  We want to be able to feel safe.  We don't want to deal with the debilitating effects of criminality on our lives and businesses.  I don't see any solution to the problem of institutional racism that results in more crime being tolerated.

This is a huge problem, because the deterrence of crime is wrapped up in aggressive policing.  You need police to make it difficult for criminals to operate, which requires some degree of harassment.  You need to deter street gangs, which requires harassing some assemblies of people in areas with a gang presence, and a lot of those areas don't have a lot of white people in them.  So if we want crime to stay low, at least some of this institutional behavior has to be tolerated and likely even encouraged.

That said, one way to get low crime with less intimidation and harassment is through surveillance.  The privacy issues associated with pervasive surveillance make a lot of people queasy (including me), but if I have to change the mix between public surveillance, crime deterrence, and fewer racist institutional behaviors, I'm OK sacrificing some privacy for less racism.  I'm not OK sacrificing public safety for less racism.  That seems like an awfully good way to get the public at large to be OK with institutional racism, which is not a step in the right direction.

But if we the public are going to rely more on surveillance and less on intimidation, it makes perfect sense for the police themselves to give up any right to privacy on the job.  From the time they clock in to the time they go off-duty, body cams need to be universal and on.  If the tradeoff is that cops don't get to have personal lives at all on duty, that seems like a small price to pay.

Beyond this, there are some gimmes out there:
  1. Training practices need to change to de-emphasize intimidation and aggression.
  2. Retraining for experienced cops needs to be a priority.  This isn't going to be hugely effective, but it's hard to hold someone accountable for doing their job the way they were trained to do it without at least giving them a chance to know that the rules have changed.
  3. Standard operating procedures need to be heavily revisited, and escalation rules need to have higher thresholds, even if it comes at the expense of officer safety and apprehension statistics.
  4. Maybe we need to trade the size of police forces for more professionalism and pay a more technocratic kind of police more.  A lot of the reforms I'm talking about here make the job more dangerous.  If you don't compensate people for that danger, you wind up attracting the wrong kinds of people.
  5. If you increase the professionalism of your police force, then your hiring practices have to reflect it.  You need to dial down the aggression criteria substantially.  As I said above, this isn't a solution for anything in the short term, but a commitment to changing the mix sends a signal to both the public and the members of the force.
  6. Complaints by the public and domestic violence charges need to be given much more weight in considering promotions and disciplinary action.  I'm reluctant to use the words "zero tolerance" here, because that inevitably leads to complaints becoming a personal weapon wielded by people who just don't like you.  But aggressive, impartial investigation of such complaints needs to be increased, and even a hint of substantiation needs to be career-limiting, if not career-ending.
  7. I can't see a way of reducing the esprit de corps of police forces, and the attendant natural impulse to protect fellow officers from discipline, without completely demoralizing your force.  But body cams are a huge deal here.  They are no doubt also demoralizing, but that's why professionalizing the force isn't a terrible idea.  Note to the public:  You need to be willing to pay for this!!!!
  8. Getting good intelligence (cf. "surveillance") to street cops is essential if you want to reduce the number of stops and harassment of innocent people.
  9. Rules of engagement on escaping suspects need to be revisited.
  10. I have no clue how to avoid the continued militarization of the police.  You simply can't let cops go up against heavily armed suspects without enough firepower to counter them.  Other countries have ways of limiting the quantities and lethality of guns in the society, but the United States doesn't.  Absent a repeal of the Second Amendment, it's not happening.  I don't think there's even a decent debate to be had on this topic.  Guns are a fact of life.  It would be nice to put an upper bound on lethality at some point, but then it'll take a couple of generations for the arsenals to decay enough to make a difference.
All of this stuff is hard and almost certainly fraught with unintended consequences.  But we seem to have reached a tipping point where this needs to be a national priority.  When that happens, the key to success is not to retreat when something doesn't work; the institutions need to keep trying.  We members of the public need to reward administrations that fail and fix things more than those that retreat to the status quo ante.  That's not something that the media is set up to allow us to do right now.  Perhaps they ought to be thinking about some reforms as well.

¹That this is so heavily politicized is deplorable.  On the right, there's all kinds of dodging and weaving going on to avoid getting officer-involved injuries and deaths into the uniform crime statistics in any meaningful way.  On the left, as I was googling some stuff related to the the ethnicity of gangs, I was surprised to discover that statistics pretty much vanish starting in about 2012.  Apparently, people are only fans of data when it doesn't gore the oxen of their constituents.

Sunday, May 31, 2020

It's Time For an Act of Faith

I see from Wikipedia that the aphorism "May you live in interesting times" is not a translation of a Chinese curse.  But it's still an excellent curse.  And the times have gotten awfully interesting.

There is a nihilist wing in the Republican Party.  It's deadly serious about tearing down the federal government.  Some of these nihilists are libertarians¹ who believe that if you degrade government to the point where it no longer functions, something will magically spring up to take its place and all will be rainbows and unicorns.  These people are idiots.  However, I'm willing to give them the benefit of the doubt and assume that they mean well, even if they're agents of ruination.  When they see what they've wrought, they may be capable of learning a lesson.  We'll call this group the "stupid" wing of the GOP.

There is another group of nihilists, however.  These people have read The Dictator's Handbook way too carefully, and believe that they can cement power in perpetuity if they can scare the public badly enough that they're willing to hand over their agency to somebody who promises to make the bad stuff stop.  Then they can do whatever they want, for whatever purposes they see fit.  Let's refer to this group as the "evil" wing of the GOP.²

Mind you, I don't think that Trump believes he's in either of these two nihilist camps.  Even a stupid nihilist has to have the ability to think about what he believes is best for society, and Trump simply isn't mentally equipped to do that.  However, he is sociopathically self-interested, which makes him a fellow traveller with the authoritarians.  In either case, he's perfectly willing to let both groups of nihilists use the executive branch as their own personal Port-a-Potty.

Both groups have the same basic formula:  First, hollow out the bureaucracy to the point where it's dangerously incompetent.  Then, degrade all norms  and customs to the point where nobody will believe a single thing that any representative of the federal government says.  Then, wait for... something to happen to bring the whole thing down.

Well, something happened.

If the stupid nihilists predominate, I'd expect that they're starting to realize that they've had a failure of imagination, and that plagues, economic collapse, and public disorder aren't what they had in mind.  In that case, some non-trivial percentage of them will reluctantly realize that Trump has to go and we'll get a slightly more competent administration, which will spend most of its political capital trying the repair the damage.  Then we'll see where we are.  This isn't a good outcome, but it's probably the least bad outcome.

I've spent most of the last three and half years assuming that "stupid" was at the wheel, with "evil" doing a bit of back-seat driving.  The rioting of the last few days is making me question that.

In any sane world, a president who's directly responsible for tens of thousands of deaths of the citizens he's sworn to protect, and presides over the utter ruination of the economy, gets voted out of office.  Based on recent polling, it appears that that's where we are right now.

But the one thing that can derail that is fear.  It does appear that the "evil" faction has figured out that they can generate any amount of chaos that they want, simply by turning fanning the (literal) flames caused by the social unrest that's sweeping in as everybody loses their minds from the dislocations caused by the pandemic and its massive unemployment.

And this is why we need an act of faith on the part of Trump's opposition.

Folks, the right wing has you figured out.  Every time you take to the streets, however peacefully, they're going to be there to discredit you and make you look like destructive anarchists.  If you go after voting reforms, they're going to make it look like you're suborning fraud.  The right has finally read Alinsky, and they know what they're doing better than you know it yourself.  They took everything you learned about how to wield identity as a political nuclear weapon and used it to form a white identity that dwarfs any coalition you can put together.  They're good at this stuff.

If you want to win--and if you don't win, there's a very good chance that the evil wing is going to prevail--then you have to believe in the American people.  Don't try to inflame them.  Don't appeal to their outrage.  Don't pit them against each other.

You're going to have to have faith in the American electorate.  I have to admit that the reservoirs of stupidity in the country are much deeper than I could have imagined, but history shows that Americans are pretty good at knowing when they're about to go over a cliff, at which time they briefly come to their senses.

Make your case--it's a slam-dunk.  Make it so thoroughly that it removes the possibility of stealing the election. Get out the vote--it'll be hard, so you have to convince people of the stakes, and then be competent politicians. Watch the polls.  And then, when you win (assuming you do), understand that your power stems from a sense that things have gone horribly wrong, not from some mandate to drive your enemies insane.

But most of all, in the immortal words of a president who I thought was pretty mediocre but now looks simply awesome in comparison, don't do stupid shit.  Don't protest.  Nobody cares about your protests.  Organize.  Behave yourselves.  The more you lower the temperature on the rage stew, the more likely cooler heads will prevail.  If they do, you win.  If they don't, you lose.

Please don't lose.

¹I consider myself to be a libertarian. However, I don't believe in magic. I do believe that freedom and prosperity will flourish if they're given a fairly basic but functional infrastructure on which to build. Things like law enforcement (of not too many laws), public health, defense, and an executor of a foreign policy more nuanced than what a third grader could dream up are pretty handy.

²There are of course non-nihilist conservatives out there.  I'm pretty sure that they won't be voting for Trump--unless his opposition is so feckless that they think he's the lesser of two evils.

Monday, May 25, 2020

Lunar Starship Cargo Deck and Airlock Concepts

I need a clean place to put a diagram I did for another thread, and this is as good a place as any.  I'll fill this out later.

Wednesday, March 18, 2020

Modern Monetary Theory and Covid-19

Looks like Covid-19 is going to force us to perform a real-world experiment about whether MMT has any basis in reality.  The amount of debt we're about to incur is going to be staggering.

Monday, February 24, 2020

Gavin Newsom For President

I am not a Democrat.  I used to be a Republican before they became too loathsome to associate myself with.  I'm a center-right kinda guy, so politically I'm pretty lonely these days.  But my number one priority in the election is to get rid of that horrible, horrible man, so I'm a Democrat this year.  I'll vote for whomever is nominated.

Except for maybe Bernie Sanders.  I'm not convinced that Bernie isn't worse than Trump.  And, since it seems that Sanders is well on his way to becoming the nominee, that's a problem.

At this point, I'd much prefer a brokered convention to one of the declared nominees.  So my strategy for voting in the upcoming Texas primary is pretty simple:  Vote for whoever can peel the most delegates away from Bernie.  I haven't decided who that is yet, but my guess is that I'll just look at the most recent polls and vote for whoever has the most support besides Sanders.

Now let's assume that my strategy, writ large, is successful, and Sanders comes to the convention with fewer than half the delegates.  That almost certainly means he won't be the nominee, which is good.  So who should be the nominee?

Bloomberg is a possibility, but he has all the personality of a piece of wet cardboard, and the Democratic base views him with extreme distaste.  You need a moderate to attract people like me, but you need someone who's leaning at the progressive side of moderate to keep the base in line.  Buttigieg and Klobuchar kinda fill the bill.  Biden fills the bill, but I think he's too damaged to win.  Warren?  Pretty far out there.

But there is somebody out there who has pretty good progressive-but-not-insane credentials, has tons of charisma, lots of executive experience, and is young enough to stir things up.  That would be the current, one-year-into-his-first-term governor of California, Gavin Newsom.

Newsom is way too green to actually run for president yet, but he has enough experience in San Francisco and California to generate some excitement, and a clean enough paper trail that he can't be drowned in oppo research.  He's feisty, speaks well, and is just the right amount of ambitious.  If the convention offered him the nomination, he'd take it.

And Trump wouldn't know what hit him.

I'm not a huge Newsom fan.  I think his policies are busy turning California into a place where only the super-rich and super-poor feel comfortable.  But that is pretty much where the Democratic Party is headed, if you leave out the Bernie Bros.  I can live with that if it means we don't have to deal with Trump any more.

Thursday, August 8, 2019

White Identity Politics, White Supremacy, and White Nationalism

Identity is the nuclear weapon of political strategy.

The two parties have used different strategies throughout their histories to cobble together winning coalitions.  Republicans from Reagan through W. Bush often led with ideological pitches, promoting limited government, but the party insiders usually concentrated on business interest groups, promising particular policies that were friendly to the contributors.  Republicans were always happy to tolerate the occasional racist dogwhistle, but it was always in the background of the ideological and interest stuff.  At no time did they ever appeal to a white identity group, because whites simply didn't think of themselves in those terms.

Identity politics has been a staple of the Democrats for much longer.  A coalition of African- and Latino-American identities were locked into the party structure about the same time that Reagan pretty much collapsed the Democratic ideological infrastructure, and rapidly became a major base for any successful strategy.  Democrats also played interest politics behind the scenes, but identity was a starting point for any successful campaign.

Then things changed.

Before I go on, I need to define "identity politics" in more detail.  We all know the term, but it seems that no two people have exactly the same definition for it.  Here's my stab at it.

Identity politics transcends the more traditional interest politics.  With interest groups, the basic coin of the realm is policy:  a group wants something done for them, and they'll vote for the party that's most likely to do it for them.  But the cohesion of an interest group usually stops at the thing they agree they all want.  An individual may be a part of multiple interest groups, and balance those interests to get the best overall deal.  Interest groups may have members, but the allegiance of those members is fluid.

But when you're a member of an identity group, the identity reigns supreme.  There may be a slate of policies that benefit the identity, but ultimately the appeal is about power, not interest.  An identity group sees itself through the lens of its disempowerment and/or oppression.  The answer to that disempowerment isn't a policy.  Instead, it's the acquisition, maintenance, and wielding of political power.

So, unlike the interest pitch, which is essentially "vote for us and we'll do the thing you want", the identity pitch is more like "vote for us and we'll give you a seat at the table, where you can make your own policies instead of relying on us to make them for you".  But the price for the power that could accrue to the identity was that its members had to subordinate all of their interests to it; picking policies a la carte simply wouldn't fly.  It was all or nothing.

Identity politics is about power, plain and simple.

2008 was the first watershed moment, where the Democrats realized how potent the identity strategy was.  Nominating an African American said "we'll give you a seat at the table" better than anything else could.  The traditional black and latino identity groups were rapidly supplemented with women, the LGBT community, and the beginnings of a specific "millennial" identity.  It was dynamite.

It also caught the Republicans flat-footed.  Not only had the financial crisis largely discredited their ideological underpinnings, but it was clear that they'd brought a knife to a gun fight.  They got crushed, and they then had eight long years to think about exactly how they got crushed.

In retrospect, in 2016, somebody like Trump was almost inevitable.  After spending lots of time wondering how they could counter the potent weapon of identity, the answer should have been obvious:  they needed to get their own identity group.  They just didn't see one that was readily available.

But Trump did.  White people aren't used to thinking of themselves as disempowered and oppressed, but Trump was able to sell them on it, and it's been the animating force in the GOP ever since.  And, once he'd managed to forge a white identity group, his group was bigger than any of the groups the Democrats could put together.  He'd brought a nuke to a gun fight, and he was perfectly happy to set it off.

To be sure, many whites were and are horrified at the idea of a white identity.  Whites have traditionally had a sort of noblesse oblige mandate to operate under what they viewed as an "American" identity, which could be slowly leavened with little bits and snatches of the best cultural elements from any ethnicity or nationality.  Many whites still believe in that.  (I still believe in that.)  But Trump built a coalition of whites who were sufficiently downtrodden and frightened to buy the into the standard identity playbook.  And it worked.

So this brings us to the first difficult question:  Is the "American" identity racist?

Full disclosure:  I am a 61-year-old white man, of upper middle class means.  I believe strongly in the "American" identity.  I believe that there is a unique American culture.  I believe that it has remained vibrant for almost 300 years by using what is now called "cultural appropriation" very effectively.  I don't view my identity as white, but I do view myself as American.

That said, I acknowledge that I'm a member of the in-group.  I've never had to fight to preserve my status.  When my culture is leavened with the best bits of other cultures, its impact on me is negligible.  In contrast, when someone of another identity shucks off his/her old identity in favor of the American one, the impact is wrenching.

Now let's look at this issue from its power dynamics.  Members of the "American" identity have been in the enviable position of picking and choosing which cultural widgets to appropriate.  It gives them the ability to think about policy and politics in terms of something other than raw power.  Other identities don't have that luxury.  They are dependent on the noblesse oblige of largely white, largely middle-to-upper class Americans.

But the alternative to the in-group granting power to various out-group identities is a dynamic where everybody views things only in terms of raw power, and that devolves into the Hobbesian "war of all against all" in short order.  So my answer to whether an American identity is racist or not is that it's the wrong question.  The right question is, "Is the dominance of a white-mediated American identity something that can be inclusive enough and just enough to beat the alternative of an identity free-for-all?"  I'd answer "yes" to that question, but it's not a slam-dunk, and it definitely requires obedience to the noblesse oblige ethos to be successful.

Meanwhile, the genie of a "white" identity is out of the bottle, thanks to Trump and his... uh... innovative political strategy.  Which brings us to the second set of difficult questions:  Is there any difference between "white identity politics" and "white supremacy" and/or "white nationalism"?

Remember:  Identity politics is fundamentally about the acquisition, maintenance, and wielding of power for the identity group.  And a "white" identity, unlike the "American" identity, must operate on an equal footing with all the other identity groups.  In short, it must acquire, maintain, and wield power, largely at the expense of other identity groups.

That sounds a lot like white supremacy to me.

"White nationalism" is a similar story, but here we need to distinguish between "white nationalism" and "American nationalism".  Nationalism is a term that's had pretty tough sledding for the last half century or so.  That said, I'm usually proud of being an American, I believe in American exceptionalism, and, as I said above, I believe in an American identity.  All of those things have at least a peripheral relationship to vanilla-flavored nationalism.  If you corner me, I'll throw a bunch of caveats in front of my answer, but I'm by and large an "American nationalist".  (I'm also a huge fan of win-win foreign policy, but when push comes to shove, I know which side I'm on.)

The considerably more problematic definition of nationalism is one that advocates for a homeland for a particular ethnic group.  Ordinarily, I'd scoff at that being applicable to anything with "American" as an adjective in front of it.  However, in light of the recent "send her back" rhetoric, it needs to said:  If your definition of nationalism is based on your race, then white nationalism and white supremacy are pretty much the same thing.   And since we've demonstrated that white identity politics and white supremacy are the same thing, the same goes for white nationalism.  QED.

So this is really, really bad.  Which brings us to our final, and most difficult, question:  How do we fix it?

If identity is truly the nuclear weapon of political strategy, then some of the language of nuclear diplomacy might be helpful.  Two terms:  "No first use" and "arms limitation".

Since identity has already be used, we're kind of in the post-Hiroshima era of identity politics.  It's been used against an unsuspecting enemy with great success, but everybody has a nuke now, and the next exchange is going to be ugly.  Going forward, both sides need to back off.

This is likely to be a bitter pill to swallow for the Democrats, who thought they had a sustainable asymmetric advantage here.  But it turns out that they don't and, furthermore, simply because of demographics, the Republicans have an H-bomb instead of a fairly modest fission device.  If the Democrats continue to use the same tactics, there will be significant leakage of voters from the "American identity" camp to the "white" one.  That doesn't end well.

Still, we're not going to do away with identity politics completely--nor should we.  Like it or not, there really are groups that are significantly disempowered, and for whom the acquisition of power is a completely reasonable political defense.

And this may be where "arms limitation" comes into the picture.  Getting ourselves out of this horrible dynamic will require that all parties understand that there have to be bright lines circumscribing the use of identity.  The natural progression of the current trend ruins everything, and ultimately degrades our most precious asset:  the American identity.

I'd like to say that I'm sanguine about being able to de-escalate this, but I'm not. Still, this seems the only way to get the friggin' genie to go back into the friggin' bottle.  Perhaps a recognition that white identity politics = white supremacy = white nationalism will start to peel away some of the Trumpkin fellow travellers.  It's one thing to accept his horribleness to enact some parts of the conservative agenda.  It's quite another to destroy the culture that you're purporting to save.

Saturday, March 23, 2019

Options For Commercial Launch of Orion

This week saw a seismic event in the NASA human spaceflight world:  Jim Bridenstine, responding to yet another set of delays in the SLS Block 1 schedule, announced that he had commissioned internal studies on how to do Exploration Mission 1, which is an uncrewed checkout of the Orion system in cis-lunar orbit, on commercial launchers.

He reiterated his support for SLS in the long run, but I don't think anybody believed him.  If this goes forward, it's certainly the end of SLS Block 1, and likely the end of SLS completely.  Opposition will be fierce, but this seems to be the beginning of the end for SLS.  Outside of its contractors and its congressional patrons, few will mourn its passing.

But we have to get Orion to TLI using a commercial launcher for this to happen.  This post will look at some ways of doing that.

Sunday, March 3, 2019

How to Use Starship In NASA's Lunar Transportation Architecture

I'm encouraged by NASA's  broad agency announcement of a lander architecture.  Unlike the the rest of the stuff being done by the Human Exploration & Operations Mission Directorate, it's oriented around commercial launchers, and doesn't seem to require LOP-G to succeed.  That's smart.

But it doesn't mean that all is well.

SLS and Orion are still hoovering up $3.7B of HEOMD funding every year.  LOP-G is eating another $500M.  That's an awful lot of money that could be redirected to building better landers faster.  It could fund a robust lunar base with robust power and robust water mining capabilities.  Mostly, it's money that could have us back on the Moon in 6-7 years instead of 10.

At the same time, in addition to the numerous political problems associated with cancelling all this stuff, one difficult technical truth needs to be faced:  Orion is the only crewed spacecraft that will be certified for operations beyond earth orbit for some time.

CST-100 and Dragon 2 are only certified for LEO operations, and neither has the delta-v necessary to insert into cis-lunar orbit and return back to trans-earth injection.

So, unless we can come up with a credible alternative to SLS/Orion, and to the 3-stage lunar lander architecture being proposed by NASA, we'll likely have to live with them.  And they're expensive.

An Obvious Question:  What About Starship?

For those of you who are still reading a hard-core space geek post and don't know about the SpaceX SuperHeavy/Starship effort, SpaceX is developing what was called, until recently when the corporate flaks wrung their hands enough, the "Big Fucking Rocket", or BFR.  Recently its two stages have been renamed to SuperHeavy (the first stage) and Starship (the combined second stage and interplanetary spacecraft).  Both stages are fully reusable, and touted to have extremely low launch costs.

We used to have fairly good numbers on BFR back when it was a completely paper rocket, but we don't know as much about SH/SS.  I've made some educated guesses that its structural coefficient got a bit higher as design progressed, as well as plugging in numbers for the Raptor engines that have been announced since we had the good numbers.  Here are the parameters I'll be using:

Dry Mass (t)280.494.8
Prop Mass (t)2,834.61,090.2
Step Mass (t)3,115.01,185.0
Structural Coefficient9.00%8.00%
Raptor-SL Thrust (SL, kN)1,7001,700
Raptor-SL Thrust (Vac, kN)1,8501,850
Raptor-Vac Thrust (kN)#N/A1,900
Raptor-SL Isp (SL, s)330330
Raptor-SL Isp (Vac, s)356356
Raptor-Vac Isp (s)375375
Number of Raptor-SLs311
Number of Raptor Vacs06
Total Thrust (SL, kN)52,7001700
Total Thrust (Vac, kN)57,35013,250
Delta-v for Landing (m/s)640 + reentry725

Note that, for the time frames we're interested in, we can assume that the Raptor has been upgraded to have a second vacuum variant, which gets higher thrust and has higher specific impulse due to optimal vacuum expansion.

So, why wouldn't NASA want to use Starship instead of SLS Orion?

There are three broad answers to that question, and then a lot of details:
  1. Really nasty politics.
  2. NASA doesn't quite believe that SuperHeavy/Starship is real yet.
  3. Even if SH/SS is real, it's not at all clear that it can be easily crew-certified--or crew-certified at all.
The politics ought to be silly, but they're not.  If Starship is on the table, especially for crew operations, then the giant pork parade that is SLS and Orion comes first into question, then comes to a grinding halt shortly thereafter.  I expect that to happen once SH/SS becomes more real, but it can't even be considered by NASA right now, lest it incur the wrath of its funders.

Objection #2 is just a combination of institutional caution and a certain amount of pig-headedness.  SH/SS is a unique design, with unique features.  It would be silly for NASA to base any lunar architecture on it before it's even off the drawing board, to say nothing of tested.

However, I'm pretty confident that SpaceX will complete SH/SS by at least mid-2022, because they need it by then in order to meet the FCC deadline for Starlink.  Things could obviously go wrong, but necessity, as they say, is the mother of invention.  I don't expect them to fail.  Still, NASA is prudent not to count on Starship before they're pretty sure it's going to work.  My guess is that confidence will be much higher by the end of 2020.

The crew-certification issue is considerably more serious.  Because it's killed crews in the past, NASA is incredibly cautious when it comes to human spaceflight.  The agency criterion for a crewed space system is that it has to have a Probability of Loss of Crew (PLOC) of 1 in 270.  None of SLS/Orion, F9/D2, or Atlas V N22/CST-100 is actually going to make that number, but they'll come fairly close, and the designs are well-enough understood that it's expected to evolve to meet the required PLOC.

Even with well-understood designs, there are strict criteria on the design for human life support and ergonomics.  So the very act of attempting to use Starship, in any flight regime, for human spaceflight comes with a non-trivial burden.  Just allowing astronauts to float around inside SS while sitting passively on-orbit will take some time.

Beyond that, Starship has characteristic that make six things pretty scary:
  1. There is no pad- or launch-abort system for Starship.
  2. If Starship is to be used to send crews directly to the lunar surface and back, it requires refueling--with the crew aboard--in a highly elliptical earth orbit (HEEO), that isn't reachable by the D2 or CST-100, and which transits the Van Allen radiation belts.
  3. Landing a crew on the lunar surface is problematic.
  4. Starship is a methalox system.  For stays beyond a day or so, boil-off of either LCH4 or LOX on the hot lunar surface will become an issue.
  5. Taking off from the lunar surface is a minor issue.
  6. The reentry regime of Starship is novel, untested, and poorly understood.
Let's cover these in more detail.  (TL;DR warning:  This closetful of anxieties going to go on for a while.  We'll return to strategy further down the post.)

Wednesday, December 12, 2018

Some Thoughts About Starlink

Elon Musk is well-known for producing highly optimistic schedules.  That's a common problem with engineers, and we all eventually learn a particular engineer's "personal multiplier":  they give you a schedule, you multiply its length by their multiplier, and that's what you write down in the official schedule.  Musk, being the chief engineer of his companies, doesn't have a manager to apply his own personal multiplier, so his schedules are usually pretty optimistic.

But, in addition to ol' Elon not having somebody to reign in his boundless enthusiasm, his schedules have real, sometimes catastrophic, impact on his companies.  He's already endured two near-death experiences in his storied career as an industrialist:  the first Falcon 1 flight test campaign, where the last launch would have bankrupted SpaceX had it failed, and the ramp up to Tesla Model 3 production.

I think Starlink is going to be his third.

Some Background

First, what the hell is a Starlink?

SpaceX has so far made its money off of manufacturing and launching payloads from Earth's surface to orbit.  By dint of making the first stages of their Falcon 9 and Falcon Heavy launchers reusable, they've dramatically dropped the cost of getting stuff to orbit.

While this "launch services" business is quite successful, the actual number of launches is still fairly modest:  SpaceX will wind up doing 20 or 21 launches in 2018.  I've estimated that, as the F9 Block 5 gets rolled out, with target reusability of 10 launches per core, SpaceX may make as much as $37.6M per reusable F9 launch, and up to $76.9M for each reusable FH launch.  On top of that, they charge extra for certain types of payload services for NASA and the military, so they could easily be bringing in $1B a year off of launch operations.

But SpaceX has huge R&D and capital expenses.  They're busy developing the "Big Falcon Rocket" and its associated "Big Falcon Spaceship" (which have just been renamed to "SuperHeavy" and "Starship", which I hate, so we're sticking with BFR and BFS for this post).  This is SpaceX's Mars-class launcher, and, if it works, it will completely revolutionize the launch business by being fully reusable, capable of lifting up to 100 tonnes to low earth orbit, and being able to rendezvous, dock, and transfer fuel from one BFS to another.  Taking these features together, BFR/BFS may be able to deliver cargo to the lunar surface for about $1000 per kg.  That sounds like a lot--until you realize that the next cheapest platform, the FH, will cost something like $12,000/kg.

[Update, 12/22/18:  John Bucknell in the comments points out that my math on the cost/kg for BFR and FH is hinky, and he's right--if we assume a reusable BFR/BFS that has to get to the lunar surface and back with no refueling on the surface.  But, if you were to deploy a Zubrin Moon Direct-style expendable lander from the BFS in LEO, it comes in at only about $250/kg.  See the comments for more details.  This needs more work.]

But BFR/BFS isn't going to be cheap to develop.  Musk has stated publicly that he expects the BFR/BFS system to cost in the neighborhood of $5B to develop.  That's a tough ask on $1B a year in operating profit.

So SpaceX has decided to become a provider of satellite internet services.  Enter Starlink.

Anybody who's used satellite internet today cordially hates it.  That's due in no small part to the delay:  When your satellite is in geostationary earth orbit, 35,800 km about the equator, the speed of light dictates that the time for a packet to get from you to a server and back is close to half a second. Satellites in GEO make for cheap antennas because they don't have to track the satellite, but they provide a horrible user experience.

Starlink is a constellation of thousands (thousands! but we'll get to that) of satellites in LEO, between 340 and 1300 km in altitude.  That makes the antennas to communicate with the satellites more complicated, but the round-trip time is well below 30 ms.  That's actually quite a bit faster than terrestrial internet, where the round-trip time is dominated by electrical cables, routers, and fiber-optic repeaters.  There are plenty of people who will pay big money to shave a few milliseconds off their round-trip time, especially financial companies, where an edge of a few milliseconds can be worth millions of dollars a day.

On top of that, the entire world is a market for Starlink.  A village in the middle of nowhere can plunk down one Starlink antenna and a wifi network and get vastly better service than the cellular network.

There's reason to think that Starlink can generated multiple billions of dollars in revenue in fairly short order.  It would rapidly eclipse launch services as the principal source of revenue for SpaceX.

But we're talking about a lot of satellites here, and those satellites need to be licensed by the FCC and other government organizations to reserve the electromagnetic spectrum to operate.

Here's where we should probably stop for a moment and consider the size of the constellation that SpaceX is proposing.  In its first phase, SpaceX has a license to launch 4409 satellites.  In the second phase, they plan to launch 7518 satellites.

SpaceX wants to build, launch, and operate 11,927 satellites.

But wait!  There's more!  FCC rules require that licensees be able to bring half of their constellation online within six years of licensing, and the whole thing within nine years.  If they don't, the constellation gets frozen at whatever has been deployed, and the rest of the license is revoked.  It's a reasonable rule:  It prevents people from buying up satellite spectrum and warehousing it for future use.

But the six-year deadline for SpaceX's phase 1 (half of 4409 is 2205 satellites) is March 31, 2024.  And the deadline for phase 2 (3759 birds) is in early November, 2024.

And those dates are where Elon's boundless enthusiasm and optimistic personal multiplier almost certainly guarantee him another near-death experience.

Building the Starlink Satellites

We're talking about an unprecedented number of satellites here.  We're also talking about a suite of technologies that aren't very mature, and which have to work at high scale for the Starlink system to be successful.

There are three biggies here:

  1. Satellite-to-satellite communications links, where the birds are constantly moving with respect to one another.  This is key to Starlink's ability to route packets from the ground at one point, to a satellite near the destination, and back to the ground at the destination.
  2. The actual satellites have to be dirt-cheap, but also reliable enough to accomplish the mission.  A small dollop of good news here:  SpaceX is intentionally limiting the life of the birds, so the usual 15-20 year design life used for GEO satellites isn't a requirement.  They'd probably be happy with 3 years.  That makes things a lot easier.  Still, considering the sheer number of satellites, SpaceX must be planning on building them more-or-less continuously, forever.  By the time they get the constellation fully deployed, the earliest birds launch will be aging out, requiring replacement.
  3. Relatively cheap flat panel antennas for the user ground stations, which have to be able to use phased array technology to track the Starlink birds as they're passing overhead.  Unlike, regular GEO satellites, these puppies don't stay fixed in one place in the sky.
SpaceX reportedly has just fired a bunch of people in their Redmond, WA group, which is in charge of the design and manufacturing of the Starlink.  Rumor was that the management of the team was resisting launch sometime next year.  That's not a super-good sign, but it does at least show and awareness that time is short.

Beyond this, I can't really say how they're going to manufacture enough birds, with enough reliability, to make things work.  But this is exactly the kind of problem that Elon and his engineers (at both SpaceX and Tesla) have proven that they're very good at solving.  Beyond that, I'm simply going to assume that the manufacturing isn't a gating item.

Some Assumptions

The rest of this post is going to examine whether there's a prayer of launching almost 6000 satellites by 2024, so this is a good time to stop reading if you're not interested in the numbers.

As I walk through this, I'm going to make some assumptions:
  1. SpaceX will launch its birds on its own launchers, at their cost.
  2. They'll make full use of both the F9 and FH, but only in reusable configurations.  (That last puts some limits on how big the payload can be.)
  3. The current SpaceX fairing, common between the F9 and the FH, is fairly small:  11 x 4.6 m, with a volume of about 145 m³.  I expect SpaceX to come out with a stretched version of that fairing for the FH.  There's a military standard, EELV Category C, which mandates a fairing that's 16 x 4.6 m, which comes out to about 228 m³.  That's what I've assumed for an FH fairing in all of the stuff below.
  4. SpaceX still has to satisfy their paying customers, so I'll assume that paying customers always get priority over Starlink launches.
  5. SpaceX is not the only launch service provider.  ULA, Blue Origin, and possibly Northrop-Grumman will all have offering in the next 6 years.  I'm assuming that whatever their (fairly modest but non-trivial) demands are on the range facilities of both Cape Canaveral (the Eastern Range) and Vandenberg (the Western Range), these companies will get what they need.
  6. I'm also assuming that SpaceX will eventually launch BFRs from a third range, based in Boca Chica, Texas, down by the Texas/Mexico border, just south of South Padre Island.  SpaceX will have full use of that facility, but there are going to be some issues with the rate at which they can do launches without annoying the environmentalists, the maritime industry, the airlines, and the residents and vacationers on South Padre.

How Big Is a Starlink, and How Many Can You Stick In a Fairing?

The FCC applications describe a Starlink weighing 386 kg at disposal time (which is after all the propellant has been burned), and being 4 m long x 1.8 m wide x 1.2 m deep, without its solar panels, but presumably with its antennae deployed.  You have to make some educated guesses about what this means at launch time.  I'm going to assume four very important things here:
  1. The "wet mass" (with propellant) of the Starlink bird will be 500 kg.
  2. The stowed configuration of the Starlink has the antennae folded across the body of the satellite.  That should make the stowed configuration 1.33 m x 1.8 x 1.2 m.
  3. The birds will actually be trapezoidal prisms, with the 1.8 m with being the base of the trapezoid.  This is pretty standard for small satellites, which cluster in rows around a central "dispenser" cylinder, which is responsible for deploying them into space from the launcher.
  4. I'm going to assume that the mass of the dispenser comes to 75 kg per satellite.
With those assumptions, I figured out how many birds each of the three fairings (current F9, Category C EELV for FH, and BFR) could hold.  That puts an upper limit on how many can be launched.  This was done using the very scientific method of making little satellite models in Powerpoint and seeing how many I could stack into the various fairings.  Here's an example, so you can share my pain:

When I totted up all the various options:, I got the following table:

Starlnks Per FairingStarlink LengthF9 BirdsFH BirdsBFR Birds
Assuming 2.0 m long birds22642232
Assuming 1.3 m long birds1.333962344
Assuming 1.0 m long birds15177500

Note that we're going to be assuming the 1.33 m length below.  If the launch configuration comes out to 2 m, things are even harder than the very hard schedule we'll see below.

The Orbits

The Starlink constellation is organized into a set of "orbital planes".  Each plane contains a certain number of satellites, spaced an equal angular distance apart.  Each plane is inclined to the equator by a certain angle.  Finally, each plane has a specific altitude above the Earth.

Here's an example:  There's a set of orbital planes that are 550 km altitude x 53° inclination.  Each plane has 66 satellites in it, which means that they're spaced 5.45° apart as they orbit the earth.  But there are 24 of these planes, which means that each plane is spaced 15° apart along the equator.

All spaceflight is done in terms of the "delta-v" budget, which is simply the amount of change in velocity you need to accomplish the mission.  Most SpaceX flights take 9200 m/s of delta-v to reach a minimum orbit.  That orbit is usually 200 km x 28.6°, which is the latitude of Cape Canaveral, the easiest inclination to get to.

I've taken a swipe at computing how much delta-v each of the orbits in the Starlink constellation will take, using an approximation.  To the 9200 m/s for the standard orbit, I add the difference in orbital speed between the 200 km orbit (7788 m/s) and the altitude of the target orbit.  This is probably a bit conservative, but it's hard to do this stuff without actually simulating the launch, which I'm not willing to do for all the configurations we have here.  Then, to get an idea of the delta-v needed to go to a higher inclination, I take the difference in the earth's rotational speed at Canaveral (408 m/s) and the rotational speed we'd have if we launched at the same latitude as the target orbit.  Again, this is only approximate.

In addition to the set of orbits, we need to know the delta-v required, and what the maximum payload is for each of the launchers in reusable mode.  Finally, once we know that, we can compute the number of Starlinks we can fly, limited by the volume restrictions if necessary.

Here's the full set of orbits for the satellites:

OrbitDelta-v CanaveralF9 PayloadFH PayloadPhaseSatellites in OrbitF9 BirdsFH Birds
550 x 53° orbit9,52717,60036,000115843062
1110 x 53.8° orbit9,82215,70030,800116002753
1130 x 74° orbit9,97814,70029,00014002550
1275 x 81° orbit10,10314,00027,60013752448
1325 x 70° orbit10,04014,30028,20014502449
345.6 x 53° orbit9,41318,40036,200225473262
340.8 x 48° orbit9,37918,70036,700224783262
335.9 x 42° orbit9,34119,00037,200224933362

Note that the very high inclinations will probably be launched from Vandenberg.  I should have re-biased them for the different launch latitude, but it was too much work.  It's close enough.

The number of satellites per launch isn't anything close to generating an integral multiple of the orbital plane.  This would appear to be bad news, because you can't just launch a rocket to one plane, then flit to another one without spending a lot of delta-v.

But there is a trick that allows you to deploy the satellites, then let them hop for free to different planes, as long as the planes are at the same inclination.  Because Earth isn't perfectly spherical, the bulge at the equator has the effect of causing an orbit to "precess", drifting slowly to the west each orbit.  The lower the orbit, the more precession there is.

To get your satellites to take advantage of this, you deploy them a bit lower than their target orbit.  This causes them to precess faster than the target orbital plane, which allows them to slowly move into position in a different plane.  When they get there, they use a small amount of their propellant to boost up to the proper altitude.  From there, all the satellites in the plane will precess at the same rate, so they'll form a fairly stable ring of birds in their orbital plane.

Above, we saw that the planes for the 550 x 53° orbits were spaced 15° apart at the equator.  Suppose that, instead of launching straight to 550 km altitude, we deploy things at 400 km.  In the 400 km orbit, the orbital plane will precess to the west 0.357° per day faster than at the 550 km altitude.  As a result, a Starlink can move from one plane to another in about 42 days.  When it gets there, it'll take only 84 m/s of delta-v to move to the 550 km orbit.

Finally, note also that I don't have any numbers for BFR in here.  That's because... well, we'll get to that.  But first, we need to talk about...


When aircraft fly, they're controlled by a highly mature infrastructure, consisting of airport operations, ground control of the runways and surrounding airspace, and finally by the national air traffic control system.  That infrastructure didn't magically appear overnight; it's the product of more than 100 years of operational experience, and the management of tens of millions of flights.  But now it works, and it's reasonably efficient.

Rockets aren't nearly as mature.  There have only been about 6100 suborbital and orbital launches in human history.  The operations needed to ensure safe launches are complex and poorly standardized. Most important, rockets are thousands of times less reliable than aircraft.  They can and do fall out the sky, zip off in unintended directions, and blow up, either in the air or on the ground.

The best concept we've come up with so far to control these things is called a range.  There are several ranges in the US, but the two we're interested in are the Eastern Range, through which launches from Kennedy Space Center and Canaveral Air Force Station fly, and the Western Range, through which launches from Vandenberg Air Force Base fly.

The range is responsible for, among other things:
  1. Managing communications to and from the vehicle.
  2. Monitoring and communicating weather information.
  3. Tracking of the launch.
  4. Clearing out airspace prior to a launch.
  5. Moving the public and ground operations personnel out of the area around a launch.
  6. Clearing maritime traffic from under the path of the launch.
  7. Coordinating recovery efforts.
  8. Ensuring that errant launches are destroyed before they can damage stuff on the ground.
Above all, the range operations are there to ensure the safety of the public.  NASA and the Air Force consider a launch to be safe if there is less than a 1 in 10,000 chance of hurting somebody on the ground under any possible track that the launch can take.

This is a lot like air traffic control, but it's vastly more primitive.  It's more like air traffic control if you expected one out of every thirty or forty 737s that took off to crash into a subdivision at the end of the runway.

Right now, before a rocket can launch, the range has to confirm that the airspace along the trajectory is clear for hundreds of kilometers.  It has to do the same for maritime traffic.  It requires days to weeks of coordination with other agencies to accomplish this.  To make things even worse, launches are often delayed for hours waiting for upper level winds to die down, or for a last-minute glitch to be debugged.  Launches are horribly disruptive to the air and sea space around them.

In 2018, the Eastern Range will likely handle 20 or 21 launches this year, and they have a "drive to 48" campaign that's suppose to get the to 48 launches per year by 2024.  The Western Range will only handle 9 or 10, and its capacity will grow very slowly.  Range capacity is by far the limiting factor on how many launches can occur.

Launch Azimuth

Each range also has a set of headings that it can accommodate.  These are a function of the geography, and are chosen to keep the rockets and the stuff that falls off of them from landing on people.  The Eastern Range can handle launch azimuths from 35° to 120° (due north is an azimuth of 0°).  The Western Range can handle azimuths from 158° to 201°.  The East is therefore good for launching things into fairly low orbital inclinations between 28° and 57°, while the West is good for polar orbits, between 70° and 104°.  (An inclination greater than 90° is a retrograde orbit, where the orbital path rotates in the opposite direction from the way the Earth rotates.  Since launches get a lot of free delta-v from the rotational speed of the Earth, retrograde orbits are hard to reach.)

Now we're ready to talk about BFR.

What About BFR?

When it comes to Starlink, BFR is... well, complicated.

One the one hand, one of the justifications for Starlink is to provide a revenue stream for BFR development, so using BFR to launch Starlink has a certain chicken-vs-egg problem.  However, a partial Starlink constellation can start to provide revenue long before the full constellation is in place, so maybe BFR, with its high capacity, is what allows Starlink to be deployed before the FCC's drop-dead dates.

Another obvious problem is schedule risk.  When you absolutely have to have almost 6000 satellites on-station by late 2024, it would be real bad if, instead of going operational in late 2022, BFR was delayed by a couple of years.  And since we're talking about something being scheduled using Elon's personal multiplier, that's a definite possibility.

But when you actually schedule things out against the existing and planned capacity in the two ranges from which SpaceX operates, it soon becomes apparent that it's very, very difficult to get enough birds on-orbit to meet the deadlines without BFR.

In addition to its huge capacity, BFR comes with a brand new range, one that's operated by SpaceX out of Boca Chica, Texas, on the coast right next to the US-Mexico border.  There's no special magic that SpaceX possesses that can make range operations super-efficient, but an extra 12-24 launch slots a year makes a big difference.  That number of launches, with the raw capacity of the BFR, makes hitting the Starlink numbers pretty easy.

But... uh, there's a problem.  A pretty big one.

Remember that 1 in 10,000 chance of injuring someone on the ground?  That implies that for BFR to be adequately safe, it needs to stay out over the water until the BFS is close to achieving orbital velocity.  I did a rough simulation of a BFR/BFS launch and, while the BFR core booster has separated and headed back to the launch site for reuse within about 150 km, the BFS doesn't make orbit until it's almost 1500 km downrange.

If you take a look at a map, you'll notice that it's pretty hard to stay out over the water when launching from Boca Chica.  There's really only a narrow range of azimuths that send the BFS through the Florida Straits, south of the Bahamas.  Fortunately, that's exactly where you want to go if you're launching heavy payloads to GEO or interplanetary orbits.

But it's not where you launch Starlink satellites.

For every orbital inclination, there's both a northerly and southerly launch azimuth.  Here they are for the Starlink orbits from Boca Chica:

OrbitNorth Azimuth from BCSouth Azimuth from BC
550 x 53 orbit42.0138.0
1110 x 53.8 orbit41.1138.9
1130 x 74 orbit17.9162.1
1275 x 81 orbit10.0170.0
1325 x 70 orbit22.4157.6
345.6 x 53 orbit42.0138.0
340.8 x 48 orbit48.1131.9
335.9 x 42 orbit55.8124.2

That's a pretty dry set of numbers, so let's plot out some of the interesting ones (leaving out the really high inclinations, which would launch out of Vandenberg) on the map, out to 1500 km:

The problem is pretty obvious:  The trajectory for the interesting Starlink orbits goes over millions of people.  Now, the actual computation of the risk to the public requires looking at every possible point of the path, estimating the chance of something falling on that spot, and then biasing that chance by the nearby population density.  So I can't completely rule out some of the southerly paths that go over a lot of Yucatan jungle, but my intuition tells me that it doesn't look good.

But there is another possibility:  Instead of launching direct to the proper inclination, the BFR could launch through the Florida Straits, achieve orbit, and then execute what's called a "plane change maneuver", where we change the inclination from orbit.

The problem with these is that they're hideously expensive in terms of delta-v.  In fact, they're so expensive that even a single BFS with no payload can't perform both the launch and the needed plane change with its total available propellant.

However, the BFS is designed to be refuelable on-orbit.  So if we launched a bunch of Starlinks, then launched two additional BFS tankers to refuel the one with the Starlinks, we have enough delta-v for some of the inclinations.

Here's the delta-v, payload, and number of Starlinks chart for BFR, as launched from Boca Chica into a 26° inclination orbit, refueled twice, and then executing a plane change to the target orbit:

OrbitDelta-v to 26 degree orbit from BCBFR Plane Change Delta-vBFR Payload With 2 Refuels and Plane Change From BCBFR Birds
550 x 53 orbit9,5183,54326,70015
1110 x 53.8 orbit9,8123,50721,90012
1130 x 74 orbit9,9685,93000
1275 x 81 orbit10,0936,66800
1325 x 70 orbit10,0315,39200
345.6 x 53 orbit9,4033,59726,60015
340.8 x 48 orbit9,3692,94158,90034
335.9 x 42 orbit9,3322,146100,00057

The number of Starlinks for each launch is horrifyingly low for a rocket that's designed to launch 100 tonnes into LEO.  That's because that number is biased by the fact that it takes 3 launches to get to the target orbit at all.  The numbers listed are an average covering all three launches.  For example, the BFS actually takes 45 birds to the 500 x 53° orbit, but we divide by 3 to come up with the average number.

So BFR is not a great platform for Starlink.  However, it does have two things going for it:
  1. The per-launch cost is being advertised as very cheap.  ($10M gets bandied about a lot, but I doubt even SpaceX knows yet.) 
  2. The BFR can launch from that lovely, uncrowded new range.  So if we're range-limited elsewhere (and we are), throwing an extra 20 or 30 launches per year at the problem helps a lot.
It should be noted, however, that even if the BFR is pretty cheap, the low average number of birds per launch gives the Falcon Heavy a cheaper launch cost per Starlink for all orbits except the 340.8 x 48° and the 335.9 x 42° orbits.  However, cost per satellite really doesn't matter if you can't get what you need launched in time.  The extra range capacity provided by Boca Chica is worth the premium SpaceX will pay for using the BFR.

So What's the Answer?

I can't say I'm completely happy with the model I put together, but I compiled some data on range and pad resources, along with the non-SpaceX demands on them, the SpaceX non-Starlink demands, and finally some semi-reasonable scheduling for the Starlink demands.  All of these come with an initial yearly launch rate, an annual growth rate, a maximum rate beyond which they can't grow, and a date at which operations can start.

Here's what I used:

Range CapacityDate AvailableResources When First AvailableAnnual Resource GrowthMax Per YearRangePadLauncher
Pad Capacity
Non-SpaceX Demand
ULA Western Range1-Jan-19110%6WestOtherA5/Vulcan
ULA Eastern Range1-Jan-19510%10EastOtherA5/Vulcan
ULA BC Range1-Jan-9900%0TexasOther-
Blue Origin Western Range1-Jan-9900%0WestOther-
Blue Origin Eastern Range1-Jan-20425%8EastOtherNew Glenn
Blue Origin BC Range1-Jan-9900%0TexasOther-
OmegA Western Range1-Jan-21110%3WestOtherOmegA
OmegA Eastern Range1-Jan-21210%4EastOtherOmegA
OmegA BC Range1-Jan-9900%0TexasOther-
Non-Starlink SpaceX Demand
Non-Starlink F9 West SLC-4E1-Jan-19510%10WestSLC-4EF9
Non-Starlink F9 East LC-401-Jan-19135%20EastLC-40F9
Non-Starlink F9 (crewed) LC-39A1-Jan-1925%3EastLC-39AF9/D2
Non-Starlink FH LC-39A1-Jan-19210%4EastLC-39AFH
Non-Starlink BFR BC1-Jan-21020%20TexasBC-
Starlink Demand
550 x 53 orbit1-Jul-19210%5EastLC-39AFH
1110 x 53.8 orbit1-Sep-20210%5EastLC-39AFH
345.6 x 53 orbit1-Jul-201210%100EastLC-40F9
1130 x 74 orbit1-Jul-19410%100WestSLC-4EF9
1275 x 81 orbit1-Jul-20410%100WestSLC-4EF9
1325 x 70 orbit1-Jan-21310%100WestSLC-4EF9
345.6 x 53 orbit1-Jul-201210%100EastLC-39AFH
340.8 x 48 orbit1-Jul-201210%100EastLC-39AF9
340.8 x 48 orbit1-Oct-221225%100TexasBCBFR
335.9 x 42 orbit1-Oct-221225%100TexasBCBFR
550 x 53 orbit1-Jul-19410%4EastLC-40F9
1110 x 53.8 orbit1-Sep-20510%5EastLC-40F9
1130 x 74 orbit1-Jul-191210%100WestSLC-4EF9
1275 x 81 orbit1-Jul-201210%100WestSLC-4EF9
1325 x 70 orbit1-Jan-211210%100WestSLC-4EF9
345.6 x 53 orbit1-Jul-201210%100EastLC-39AFH
345.6 x 53 orbit1-Jul-201210%100EastLC-40F9
340.8 x 48 orbit1-Oct-221225%100TexasBCBFR
335.9 x 42 orbit1-Oct-221225%100TexasBCBFR

With this, I got:

  • 2210 phase 1 Starlinks by the end of 1Q2024.
  • 3830 phase 2 Starlinks by the end of 4Q2024 (which actually isn't quite good enough, but it's literally close enough for government work.
Both of these numbers meet the FCC's half-constellation "use it or lose it" rule.

The big takeaway, however, is that I simply can't get this work without two things:

  1. Starlinks starting to launch from the Eastern Range on both FH and F9 platforms by the third quarter of 2019--about 7 months from now.
  2. The BFR launching at least once a month starting in 4th quarter of 2022, and growing by 25% a year thereafter.  
So the success or failure of Starlink comes down to executing pretty crisply on the BFR, and getting the Texas range humming along at a pretty good clip as soon as the BFR is ready to go.

Things would get a lot easier if the Eastern Range wasn't just driving to 48, but instead went to something like 56-60 launches a year.  But my guess is that that isn't going to happen.  As a result, a lot of the burden of executing on this will fall on Boca Chica and the BFR.  (Remember:  birds go up on the BFR only every third launch; the other two are refueling runs, which likely require that SpaceX has a fleet of at least 6 BFRs to get started.)

Things also rapidly get out of control if SpaceX can't start launching Starlinks in high volume some time in the next 7 or 8 months.  That's not a lot of time.

What About Regulatory Relief?

SpaceX has repeatedly asked the FCC for a relaxation of the the "use it or lose it" rule, given that coming even close will demonstrate their earnestness in using the licensed spectrum, and also given that the range restrictions aren't really going to be their fault.  So far, the FCC has denied these requests, but have invited SpaceX to apply for the waiver at a later date.

So it's not completely implausible that the FCC might take pity on them if things are going pretty well, but they can't quite drum up the capacity soon enough.

On the other hand, SpaceX as a company and Elon as a person have made some powerful enemies, and Starlink poses an existential threat to an awful lot of vested interests:

  1. One of the best ways of killing the BFR is to kill the funding needed to complete it, and Starlink revenue is an integral part of that funding. Boeing, Lockheed-Martin, and Northrop-Grumman are all painfully aware that the success of the BFR could easily take them out of the launch business.  When you hear the phrase, "military-industrial complex", these guys ought to be in your mental picture every time.  They have something like 70 years of experience lobbying legislators and regulators in Washington.  SpaceX is a babe in the woods compared to them.
  2. The telecom industry is another heavily entrenched, politically sophisticated industry that stands to lose big from Starlink, although this is a mixed bag:  Starlink would be a definitive, permanent answer to the mobile telecom industry's need for backhaul bandwidth (the communications links that take stuff from the cell towers and dump it to the terrestrial network, and vice-versa).  But it's also kind of a nightmare, because Starlink has the ability to grow to be a formidable competitor to incumbent mobile networks around the world.
  3. Finally, there are a whole bunch of people in Washington who cordially hate Elon Musk.  They don't like his flashiness.  They don't like his politics.  They don't like the fact that he makes no bones about wanting to squeeze the life out of the world's fossil fuel infrastructure as quickly as possible.  None of these people would piss on him if he were on fire, to say nothing of going to bat for him with the FCC. 
The bottom line here is that SpaceX would be crazy to count on regulatory relief.  Yes, they might get it, but there's an excellent chance that they won't.  They'll be planning accordingly.


The bottom line is that Starlink is doable, but it's really, really, really tight.  Even minor hiccups in either the manufacturing of the satellites or SpaceX launch operations could cause them to miss the crucial milestones.  Significant delays in the BFR can mess things up.  A serious launch accident can mess things up.

I'm not quite sure where the crunch will come for Elon and his group.  It could be early next year, if the Starlink satellite development isn't proceeding smoothly.  By 2020, SpaceX will need to be making Starlinks at a rate of about 600 a year.  By 2022, they'll need to be making 1500 a year.

The crunch could be with BFR, or with the Boca Chica range.  Even fairly modest delays put the phase 2 deadlines in serious jeopardy.

Or it could just be the sheer, grinding, sustained operational tempo that's required to pull this off.  Make no mistake:  Starlink will require SpaceX to go flat-out, launching as many missions as they possibly can, for at least the next 10 years.  Launch crews will get worn down.  Key people will quit.  It's going to be a challenge to maintain an organization that's robust enough to deal with the inevitable hiccups and still keep going, satellite after satellite, launch after launch.

It's going to be hellish.  But one thing's for sure:  If SpaceX can pull this off, the world will be changed forever.  I'm rooting for them.  But I'm worried that failure could pose an existential threat to SpaceX as a company.

Update 12/17/2018:

One of the things that hadn't occurred to me is that SpaceX can launch the BFR through the Yucatan Channel and get to a 33.2° inclination.  That then makes the plane changes about 1000 m/s cheaper, which is huge.

I've reworked the number of birds per platform, using this idea.  I've also figured out exactly how much prop is needed to reach the target inclination, and assumed that a BFS tanker (aka a BFS with no payload and some extra prop in its tanks) can loiter waiting for the next launch of Starlinks, somewhat reducing the number that have to be launched.  I've assumed a 20% boiloff while loitering--that number is derived purely by Rectal Extraction.

Here's what I get:

OrbitDelta-v For F9, FH Canaveral (Also Vandenberg but it's somewhat wrong)Delta-v Boca Chica to 33.2 InclinationBFR Plane Change From 33.2 Delta-vF9 PayloadFH PayloadBFR Payload With Refuel and Plane Change From 33.2BFR Refuelings Needed For Plane ChangeBFR 20% Boiloff Adjusted Launches Per Load of Starlinks
550 x 53 orbit9,5279,5082,61017,60036,00088,3002.63.72
1110 x 53.8 orbit9,8229,8032,61015,70030,80069,80034
1130 x 74 orbit9,9789,9595,08214,700#N/A#N/A#N/A#N/A
1275 x 81 orbit10,10310,0845,85014,000#N/A#N/A#N/A#N/A
1325 x 70 orbit10,04010,0214,54314,300#N/A#N/A#N/A#N/A
345.6 x 53 orbit9,4139,3942,64918,40036,20095,9002.63.72
340.8 x 48 orbit9,3799,3601,98518,70036,70098,2001.72.84
335.9 x 42 orbit9,3419,3221,18319,00037,200100,0000.92
OrbitF9 Birds Per LaunchFH Birds Per LaunchBFR Birds Per Cargo + Prop LaunchesF9 Cost Per BirdFH Cost Per BirdBFR Cost Per Bird
550 x 53 orbit306241$396,667$280,645$243,902
1110 x 53.8 orbit275330$440,741$328,302$333,333
1130 x 74 orbit25#N/A#N/A$476,000#N/A#N/A
1275 x 81 orbit24#N/A#N/A$495,833#N/A#N/A
1325 x 70 orbit24#N/A#N/A$495,833#N/A#N/A
345.6 x 53 orbit326244$371,875$280,645$227,273
340.8 x 48 orbit326260$371,875$280,645$166,667
335.9 x 42 orbit336286$360,606$280,645$116,279
F9 CostFH CostBFR Cost

Note that I've also included a per-Starlink launch cost for each of the three platforms.  My cost numbers are derived from an exercise I did a while ago, looking at SpaceX's launch costs for the F9 and FH assuming that cores got reused 10 times.

With these new numbers, I can get both the phase 1 and phase 2 deadlines met, using only 48 Eastern Range launch slots and delaying the BFR until 2Q2023.  However, it requires a pretty aggressive ramp, both on the Eastern and Texas ranges, to get there.

Yet Another Update, 12/19/18:

Fixed the previous table--I had the wrong F9 and FH costs.  BTW, my F9/FH cost model is here.

I've also gone through the scheduling exercise in a bit more detail, which has allowed me to put a total cost on both the manufacturing and launch of the entire constellation.  Assuming it costs $100K to build a Starlink bird, the total cost is about $4.4 billion.