Follow Slashdot blog updates by subscribing to our blog RSS feed

 



Forgot your password?
typodupeerror
×

Comment Re:Joe Biden for President? (Score 1) 435

I doubt, Joe Biden will score even so much as a nomination â" despite his desires â" which will, of course, be even more embarrassing for the Democrats, than him losing the subsequent election.

This is likely the number one reason why no one has attempted to assassinate Obama. They know we would get Biden in his stead.

Comment Re:Failed state policies (Score 1) 435

Nice red herring on the infant mortality rates.

Cuba doesn't count the deaths of infants that die within three days of being born. Those are considered miscarriages, and don't contribute to the numbers. In the US, any birth that still has a heartbeat outside of the mother is considered a live baby. If it dies moments later, that's "infant mortality." Many (very sensible) countries around the world don't do the math that way, resulting in complete apples/oranges when you compare the stats.

Regardless, you're trusting ANY numbers out of Cuba, where the government jails and sometimes kills people who say even very non-specific things that run counter to the totalitarian propaganda?

Comment Re:About Fucking Time (Score 3, Interesting) 435

Only President Obama could get gas to $2.50

Gas is that low despite him, not because of him. Get your basic facts straight.

end 2 wars

Which two was that? There's more war in Iraq than there was when he took command, and the war in Afghanistan that he said was the important one is still going on. There's also some new NEW war going on in Syria, where he's now got our forces involved, and we have some lead being slung around in places like Ukraine. "End" two wars? Which ones?

get bin Laden

You mean, be in office when the people who were already working on the task before he took office finally got things lined up and got it done? His main contribution: watching from the situation room. And the intel/SF people who made it happen aren't very happy with him leaving the Pakistani doctor who helped make it possible to twist in the wind after the deed. Classy.

bring unemployment below 8%

That fake number only works if you pretend that huge numbers haven't simply given up looking for work. The real number is much higher than that. Which you know. Which everyone knows. Please, show a little integrity.

then be told he's failing as president

Well, he is. So there's something to be said for being honest about it.

Comment Re:Not a cargo ship (Score 3, Interesting) 116

Once again, when not using made up numbers, Green energies are the same.

Which is a very odd claim - since you produce no numbers whatsoever for "green" energy.

And you forget that natural gas isn't just a source of BTU's - it's also a major feedstock for a variety of industrial processes. (A significant portion of "oil derived" plastics are actually derived from natural gas.)

Comment Re:As long as they get close it's a win (Score 1) 81

No, I missed the quoting the part that was (more-or-less, mostly less) correct. The parts I quoted were parts that you were wildly incorrect on, as there's considerable distance between what has been tested, and what they are testing. Even so, you're still wrong. Miss the target, by even a little bit, and it's a loss. Land hard and lose the vehicle (not due to sea state) and it's a loss. Tip over and lose the vehicle and damage or lose the barge (not due to sea state), and it's a loss.

So yes, it does matter if they miss, it does matter if they land hard or tip over - because the whole goal of the test is to demonstrate a successful pinpoint landing. You don't really seem to grasp what's being tested here and why.

Comment TANSTAAFL (Score 1) 81

However, the cost of not having to rebuild the rocket every time is much more significant. Even if they can only reuse it a few times, that's a lot of production cost being saved.

The money saved by not having to produce a new vehicle is offset by the money spent on fixed infrastructure and on recovering and refurbishing the vehicle for the next flight. Airline travel is as a cheap as it is because they've gotten between-flights maintenance down to essentially zero (basically only emergent work) - the expensive refurbishment and refitting occurs at intervals of months to years. (And the amortized costs of the facilities for doing so are spread over a large number of aircraft and a very large number of flights.) The Shuttle was expensive as it was because between-flights maintenance costs were very high. (And the amortized costs of the infrastructure were spread over a very small number of vehicles and small number of flights.)
 
So, if a first stage (new-in-box) costs $x million and refurbishment costs $.9x million (including the amortized portion of the fixed costs), then it'll have to fly ten times just to break even. The break even point calculation is very sensitive to flight rate, flight interval, and the number of vehicles in the fleet. The hope is, over a long time frame, to reach civil aviation levels... but there's a long way to go between here and there. (Particularly in light of the low flight rate of F9 launches that have sufficient spare payload capacity to allow them to be recovered.)

Comment Re:As long as they get close it's a win (Score 2) 81

If they can show over a couple attempts that they get close to the target then they can move to doing this over land. They have already proven they can do this in Texas many times.

There's a reason why they're flying all these attempts over water - they haven't done it in Texas even so much as once. The flights in Texas have been "take off, go a short distance up, then land more-or-less right back where you started" - which isn't the difficult part (so far as flight control is concerned, it's more of an engine control problem) as small errors have no time to propagate. The difficult part (from the flight control POV and the reason they are testing on a barge) is the boostback and retro burns, where even small errors in attitude and delta V propagate into significant errors by the time you hit your hovering gates (and is thus an engine control *and* a flight control problem). Another issue, also not tested in Texas, is the aerodynamics and flight dynamics of the returning stage (especially in the high speed regime), and indeed these issues caused a problem on the first attempt.

So no, coming close isn't a win. They're going to have to demonstrate pinpoint recovery a number of times before anyone is going to let them even consider attempting it over land.

Slashdot Top Deals

The Tao is like a glob pattern: used but never used up. It is like the extern void: filled with infinite possibilities.

Working...