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Comment Re:Video from the barge (Score 4, Informative) 113

Kind of makes me wonder if using the barge as such a small target is contributing to the hard landings, simply because it's such a tiny target relative to the area that the rocket has to come down on

Since the first attempt hard landed because it ran out of attitude control gas, and the second hard landed because of a control valve problem... how would a larger target have helped? In case of the first attempt, you've still got to control your attitude regardless of the size of the field. In the second, the size of the field is irrelevant if you can't properly control the vehicle in the first place.

Seriously, don't be misled by the frantic activity in the final seconds of the most recent attempt. That burst of activity was the vehicle attempting to null it's horizontal velocity and then trim it's attitude before landing - something it has to do regardless of the size of the field.

The basic flaw in the landing sequence isn't the size of the target, it's the design of the vehicle. Its minimum T/W ratio is well over unity at landing, meaning it can't hover, can't ease itself down, and you have to take great care to not end up with positive vertical velocity. The only way it can land (with any reasonable sized target) is to approach at high speed, then at the last second try to null horizontal velocity without excessively reducing vertical velocity (I.E. bouncing), followed by a return to vertical and touchdown.

You could avoid this by having a circle of paved ground a quarter to half a mile in diameter - but that's not cheap to build or maintain given the need to resist a rocket's exhaust. Long term, given that the tests are essentially free*, it's cheaper and easier to figure out how to land precisely on a smaller target.

* The first stage is bought and paid for by the launch customer - and so long as the added equipment for landing poses no undue risk during ascent, they don't care what happens to it after separation.

Comment Re:Are the two networks truly separated? (Score 1) 113

Exactly this. I'd like to think that there's an air gap (ahem) between the avionics and passenger networks, and that it's impossible to access the avionics system from the passenger compartment. I'd also like to think it doesn't rely on security through obscurity, like "we run our API server on port 81 instead of port 80, ha-HA!". Come on, Slashdot: we have to have at least one aerospace engineer in here, don't we?

Comment Re:Larger landing area (Score 1) 342

It sure seems that if a larger landing area was available, so that the rocket didn't have to lean so far to adjust to a very small target and thus could prioritize staying vertical, it would be able to land successfully.

No so much as you might think - you still have to trim and eventually null your horizontal velocity, and null any horizontal residuals arising from trying to remain vertical. It's a complicated problem, even if you're just aiming for an arbitrary landing spot in a larger landing area.

On top of that, the crash seems to have been caused not by prioritization, but by a control valve operating sluggishly causing the response time to go out of limits. Even if you're just accepting a landing wherever you're coming down, if the control system gets out of phase you're screwed.

Comment Re:A first: We should follow Germany's lead (Score 1) 700

If your charity is providing shelter for the homeless, but they have to pay 10 bucks per night for the bunk-bed, you are not non-profit.

That test fails. What if it costs $50 per night for the bunk-bed and the rest is subsidized through external donations?

If your mega-church is providing "healing for the sick", but they have to pay $200 to enter, you are not a non-profit.

And if that $200 turns into renting clinic space and buying supplies to provide free medical care to poor children?

My point is that the answer to these questions is never simple, and if you think you've found a simple definition that neatly covers everything, it suggests you're likely missing something.

Comment Re:A first: We should follow Germany's lead (Score 5, Insightful) 700

but if a megachurch can afford a huge all-glass cathedral, $ multi-million salaries for the charismatic preacher begging for more donations, and toys like private jets and limos, nope, that's a for-profit enterprise, even if you cook the books so there's no money left over at the end of the day.

I'm not disagreeing with you, because I think that stuff is disgusting. But. As a programmer, how would you write a function that returns a boolean value: "is this church a legitimate non-profit?" Because that's ultimately what you're asking, and I'm having a hard time formulating such a thing.

Test cases:

* A small-town church with a pastor who has four different congregations: True
* A huge all-glass cathedral, $ multi-million salaries for the charismatic preacher begging for more donations, and toys like private jets and limos: False
* A small local all-volunteer charity that feeds the homeless: True
* A small, all-volunteer, poorly run charity who means well but sucks at their mission: True
* A large national charity with a well-paid CEO who effectively uses their resources to do amazing things: True
* A large national charity with a well-paid CEO who isn't very effective, but everyone agrees means well: True?
* A large national charity with a well-paid CEO who doesn't effectively uses their resources: Um...

Step one: agree on the test cases. Step two: specific the input parameters that lets you distinguish between outcomes. Step three: non-profit?

Comment Re:Why the hell ... (Score 5, Informative) 119

Why oh why would you put the parsing of HTTP at the kernel level?

They probably saw that FreeBSD has been doing it for 15 years and thought it might be a good idea.

This is the kind of stuff which needs to be in userspace, not the friggin OS.

Apparently not everyone agrees with that.

I'm in no way a Microsoft apologist, but it's not like a senior engineer rolled out of bed one morning, smoked some crack, and yelled "hey, let's break some crap today!" Lots of stuff is done in kernel mode in Linux and the BSDs - like all kinds of graphical mischief - and MS probably does the same things for the same reasons.

Comment Re:Basement-dwelling Introverts (Score 1) 137

So just send people who are happiest sitting at the same keyboard for days if not hours on end, with minimal human interaction.

The truth is, that kind of person is damn near the worst choice possible and the polar opposite of the kind of person you need.
 
You don't need someone who can't or won't deal with individuals. You need someone who can deal with forced close quarters interactions with individuals while also being able to deal with near complete isolation from society. These are two very different kinds of people.
 
The crew of a Mars-bound craft will invariably be forced into contact with each other due to the small size of the vehicle. On top of that, they must come together as a team because much of what they'll be doing will be done with close coordination in close proximity to each other. Someone who willingly isolates himself (or worse yet deliberately isolates himself) psychologically and socially from his crewmates over a long term is thus more of a liability than an asset because he'll have a hard time coming together and remaining as part of the team (if he can do so at all).
 
The latter (near complete isolation from society) is actually the difficult part. Unless they're truly out at the end of the bell curve (and thus edging on being mentally ill), all but the most introverted basement dweller has email, guild chat, chatrooms, forums and blog comments, social media, and other forms of real time or near real time communications. (Not to mention shared experiences and events as raids, game releases and updates, movie releases, etc...) They've isolated themselves from close physical contact with individuals, but they're still in close social and psychological contact and interaction with society. (Very few people actually willingly completely cut themselves off from society.) Onboard a Mars bound spacecraft, that close contact and interaction (fostered by real time and near real time communications) and those shared events and experiences will be nearly completely absent - not just due to speed-of-light delay, but due to limited communications bandwidth.
 
Disclaimer: Former SSBN crewman, been there, done that, got the t-shirt. (Or at least about as close as you can get without actually being an astronaut.)

Comment Re:Push technology is for phones, not computers (Score 1) 199

There is ZERO reason to have this on desktop PC's even for things like IM programs.

Why? Do you like having to keep browser tabs open for your IM, e-mail, calendar, etc? Or to use some extension or plugin? I always keep gmail (actually, inbox) and calendar tabs pinned, but with push notifications I might not have to bother with that any more.

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