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Comment Re:Could be worse (Score 2) 626

I used to do development and testing for explosives detectors. Nitro-toluenes are very, very hard to get off your skin and clothes. I was pulled aside for random searching and swabbed for explosives.

In a past life, I was a contractor who spent 3 months bouncing between FOBs in Iraq and Afghanistan. The day before I flew home, I was on a CH-53 flying back towards Kuwait where i caught commercial back to Canada. I was sitting next to the door gunner, and as we flew along I think we crossed a range, and he let loose a dozen or so rounds out of the .50 cal. I spent the entire trip home thinking "Please don't swab me, please don't swab me..." and thankfully they didn't. Of course, trying to explain where you had been for three months when you had two in/out visas from Kuwait and a blank spot in between was another matter...

Comment It's QoS (or the lack thereof) (Score 1) 325

The problem with your link isn't that your browser is opening up multiple connections, it's that your satellite link has shitty (or non-existant) QoS. I run a satellite network to a remote site, that is serving about 60 users using 3.3Mbps. Between WAAS and some carefully tuned CBWFQ, it's slow but reliable, you click on something you can be pretty sure that it will load. Heck, this link is also running VOIP for everyone, and calls are nearly toll quality even when the network is saturated (which is most of the day and evening).

Comment Re: Great strides (Score 1) 129

I'd wager that the most likely cause of failure would be a fatigue and/or structural failure in the rocket, but I'm just making an educated guess. The high stress systems (turbopumps, engines, cryo systems) have been strongly tested by the static firings. That said, 50 years of aerospace technology has taught a lot about how aluminum ages and operates under stress, though of course we still saw a structural failure on CRS-7, so who knows?

Comment Re: Awesome (Score 1) 129

Well, when CRS-7 failed, it did destroy a reasonably valuable piece, the International Docking Adapter A.

Interestingly, the Dragon would most likely have survived (and will now in the case of a similar failure) had the software been setup to deploy the parachutes in case of a breakup like that. Unfortunately, the IDA was in the trunk, which wouldn't have been saved by the parachutes.

Comment Re: Great strides (Score 5, Informative) 129

I don't normally reply to ACs, but the fuel cost is roughly negligible. The propellants used for landing are mostly the contingency propellants they woudl need to cary any way in case of a problem with one or more engines. As far as refurbishment costs go, we'll see, but the second landed booster has had at least 10 full duration test firings since landing, without anything going boom, and minimal refurbishment.

And finally, ok, so SpaceX is getting government funds. Do you think that ULA isn't? Competition and different approaches are a good thing. From a strategic perspective, the United States Government needs to maintain launch capabilities for its own payloads. It's better to have multiple options for those launches.

Comment Re:so what? (Score 1) 101

why do millenials need an app to measure fitness? just lift a weight and run some, maybe play a sport

I'm no millenial, but the damned little thing provides me with just enough motivation to get up off my ass and go for a walk. I have a few other people that I "compete with" but it's mostly just about actually that little prompt to actually move around. I know that the times my fitbit has broken, I've slacked off.

Comment Re:must be the lead (Score 5, Interesting) 118

So local cathedral in Vancouver just underwent a major restoration where they replaced the roof. The church is located on one of the busiest intersection sin the city. As they did their work, and removed the old roof, they ran into the unanticipated problem of significant amounts of lead dust filtering down into the rest of the building. It was then that it dawned on them that the church had been sitting on the busiest intersection in the city for 100 years, and for a significant portion of those, vehicles had used leaded gasoline. The remediation of the lead added about 25% to the cost of the renovation.

Comment Re:Pirst Fost (Score 2) 151

As bad as Uber drivers may be, Taxi drivers are no better. At least around here, they're probably the worst, most poorly behaved drivers on the road. I took a cab home from the airport, a while back, and the idiot was speeding up the curb lane, speeding, pushing amber lights, cutting people off, etc... and then had the gall to be pissed off when I refused to tip him (I do not reward bad behaviour... had he driven like a sane person, I would have tipped him adequately). When I'm driving myself, I basically give cabs no quarter. Where I'd slow down a hair to be courteous to another driver to let them merge... with a cab? never. They shat their bed, and now have to live with it.

IMHO, the regulations should be changed so that any car that passes the various standards (Safety, meter accuracy, insurance, etc... ) should be allowed to be a cab. The Taxi cartels need to be done away with, but also companies such as Uber need to operate in an adequate regulatory environment to preserve public safety. Rates should be regulated, and drivers should be fairly compensated. And any traffic fines should be strictly enforced, and doubled, for professional drivers.

Comment Re:I thought diesel ran cleaner (Score 1) 243

Typical compression ratio in a Diesel engine is somewhere around 20:1, vs a gasoline engine that's running 10:1 or there about. That means that your 3.2L V6 is pushing 46500L per minute of air through it (3.6/6*20*1550*3 = 49600. Your gasoline engine is 3.2/6*10*1800*3 = 28800L/minute.

Basically this is displacement/cylinder * compression ratio * RPM * number of intake strokes per revolution. As such, your Diesel is pushing just under double the amount of air compared to the gasoline engine.

Ever wondered why diesel tail pipes are a lot larger than gasoline ones? This is why, diesels move a lot more air.

For the record, I drove an '06 TDI, and won't trade it for a gasser until it falls apart.

Comment Re:No plutonium is not an issue here (Score 4, Informative) 107

No, the lead was a simulator for the plutonium pit. The Depleted Uranium tamper surrounding the weapon isn't particularly radioactive. The tamper is there for two reasons, one the density and high inertia of it confines the chemical explosion long enough for the nuclear reaction to occur. Secondly, fast neutrons from the plutonium chain reaction then cause the tamper to fission, generating another portion of the weapon's energy.

As to why you're flying the aircraft with a weapon such as this, it's because it is supposed to be a live training mission, testing all the electrical interfaces, mission profiles, etc... and without the plutonium pit, the weapon is inert from a nuclear perspective. At that point, they also didn't have really viable simulators that could be used as a proxy.

Comment Re:Electric cars won't take off (Score 1) 174

Oh, so fuel prices reach what they are elsewhere in the world? most recent price I saw for regular here in Vancouver was $1.19 CAD/L, which works out to $3.40 USD/gallon, though that's a significant improvement over what it was a while back when it sat at $1.50 for quite a while.

Face it, the US has artificially low fuel prices, you guys are just starting to join the rest of the world. The world won't end, the sun will still rise and set, and the bitching will continue.

Comment Re:breaking news (Score 3, Informative) 190

Especially when there's no fucking reason to fuel up while crew are aboard.

Actually there are a number of reasons to fuel right before launch, some specific to SpaceX/Falcon 9 and some in practice.

1) If you fuel the rocket you have a lot of people that are working in and around the rocket when it's in a hazardous state for a long period of time, with no means of escape. Think of all the technicians in the white-room who are strapping the astronauts into the capsule etc... The astronauts, when strapped into the capsule, have a good escape system that will get them away from the fireball.

2) In the old days, it did take hours to load propellant into the rocket, and having your astronauts strapped into their seats that long was lunacy. With the Falcon 9, that process is down to 40 minutes.

3) The Falcon 9 requires this. The design as it stands depends on sub-chilled propellants to achieve the required performance. This means that the rocket can't sit for long on the pad fully loaded, certainly not long enough to strap in the astronauts.

All in all, with the way that the Falcon 9 works, and the reliability of the launch escape system, it's actually safer to load the propellants when the astronauts are already packed in.

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Long computations which yield zero are probably all for naught.