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Comment: Re:I Disagree with the Summary (Score 4, Interesting) 341

Someone in the Youtube comments says "The flight profile veers the booster off to the side on purpose so the exhaust from the final burn isn't directed at the barge where it could do damage"

If this was a planned manoeuvre, I'm much happier. Can anyone confirm this statement?

Comment: Re:I Disagree with the Summary (Score 1) 341

I was shocked at how abrupt and extreme the pitch changes were. I think so long as it needs such gross adjustments so close to landing, landings will be unreliable with a significant chance of failure. It is not at all like the tidy landings made by the Grasshopper test vehicle.

Two engineering changes which could make a big difference are lower minimum thrust (so it can approach the landing with lower acceleration) or lateral control rockets (RCS) at the top of the stage.

Comment: Re:Perfect security (Score 1) 460

by Michael Woodhams (#49426117) Attached to: Planes Without Pilots

"... any modern airliner can be specced with options to fly itself from gate to gate on an ordinary day ..."
Can you tell me more about this? My understanding is that taxiing and take off are always performed manually. Unless it surrendered control to a central airport system, I don't see how autotaxi would even be useful, as actions are so dependent on other traffic.

Comment: Re:This guy has a better idea (Score 1) 221

by Michael Woodhams (#49208569) Attached to: New Concept Tire Could Recharge Car Battery

How about using supercapacitors to convert 5 seconds of 60kW into 15 seconds of 20kW (less losses)?

5 seconds of 60kW = 300kJ. Supercapacitor energy densities are in the range 0.5 to 15 W-hour/kg according to Wikipedia. Say 5 Wh/kg, = 18000 J/kg, so you'd only need a few kg of supercapacitor to make this work. The only price I find is US$2.85 per kJ in 2006, putting the cost at around $1000, probably much less now (but there will also be costs beyond just the supercapacitor.)

You could also make this an option - not much point paying $2000 for this capability if the car is going to be in Singapore.

Comment: Re:Why can't they fairly negotiate? (Score 1) 61

I can't tell if you're serious.

The idea of landing a stage on rocket power for reuse has been around for decades (DC-X comes to mind, there may be earlier examples.) As rockets generally launch seaward for safety reasons, that you might want to land one at sea is obvious. The idea of using a ship as a landing platform has also been around for decades. There is nothing that should be patentable in the big idea "landing a rocket on a ship".

Within this general idea, there are bound to be many smaller patentable ideas: e.g. method for automatically securing a rocket to a deck when it could be up to 15m away from the target landing point.

Comment: Re:International waters (Score 3, Informative) 61

Furthermore, that is why rockets launch from the east coast in the first place: if something goes wrong, the flaming debris comes down over the sea.

However, SpaceX are aiming to do a return to launch site for recovering their stage I boosters. (This surprised me - this must use more fuel than land-at-sea, and the mass of that fuel is directly subtracted from your available stage II payload.) The landing at sea is an interim measure while they prove the technology (because of the afore mentioned potential for flaming debris.)

Comment: Instantaneous launch window (Score 1) 75

Also: both this launch and the previous one (space station resupply mission) had an "instantaneous launch window", meaning that any delay at all means they scrub for the day. Why is that? What is so magical about their launch time that they can't accept a one minute delay? And how much does it cost to scrub a launch for a day?

Comment: Where do I go to get news about these launches? (Score 1) 75

Just yesterday I looked at the SpaceX website's news page specifically to find out when the next rocket recovery attempt would be, and it said nothing about this. I just happened to check /. in time to tune in to Nasa TV 5 minutes before launch time. (Incidentally, they've scrubbed the launch for today.)

"I got everybody to pay up front...then I blew up their planet." "Now why didn't I think of that?" -- Post Bros. Comics

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