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Comment Re:I've figured out the cause of the crash (Score 1) 491

It is _possible_ to land reasonably safely in the ocean. It requires a lot of skill and luck. Basically the plan has to orient in the same direction as the swells, slow down to just above stall speed (still about 150 knots IIRC), take a nose high attitude to prevent cartwheeling, and basically 'land' as slowly as possible, preferably picking the moment of contact on a wave peak. This of course works much better when the water is flat, which it rarely is in the southern Indian Ocean and the Southern Ocean - read up on the "Roaring Forties". Even once you have 'landed', the high waves have enough force to start stressing the plane to the breaking point, and as soon as the doors open the waves are going to play hell with rafts and people trying to get out on them. It's not quite like boarding a raft in a hurricane, but it's close.

Comment Re:Flight recorder (Score 1) 491

A friend of mine used to work for a company that built satellite receiving antennas, working on the software for the mounts. One of the things they would do is peruse the published satellite ephemera - I think each satellite's data was 80 points - and look for places where no satellites officially existed. Then they'd point their antenna there, and bingo! They found several military satellites that way.

Comment Re:Flight recorder (Score 1) 491

A British airliner that disappeared a few miles from the airport back in 1951 was recently discovered. Its next-to-last messages (via Morse Code) were that it was close to landing. Its fate was unknown until 1998. And that was on land. The area to be searched, given the best possible scenario with present data, is IIRC 22,000 square miles, about the size of Rhode Island, Massachusetts, Connecticut, and New Hampshire combined - about 1/3 of New England or about the same as Latvia or Lithuania, or 2/3 of Scotland. This is a much harder problem than the Air France jet of a few years ago, where they knew within a small range where the plane was likely to be.

I don't think it's possible for the pilot to shut off the flight recorders, at least without climbing all over the airplane. They are independently powered and situated at the back of the plane. They may only be accessible from outside the plane - I don't know this for sure.

Comment Re:Flight recorder (Score 1) 491

To add to that, that area of ocean has about the worst conditions for ships, planes or helos. The "Roaring Forties" is not named that for nothing. A typical 'nice' day there will have 30 to 60 knot winds and 20 foot seas, plus a lot of fog, clouds and rain, air temps in the 0C to 10C range, and sea temps of 0C. Of course, if that's too balmy, there's always the Furious Fifties and Screaming Sixties. The Indian Ocean gradually becomes the Southern Ocean, which is the only ocean that has no barriers to its west-to-east current to slow it down, and the air above it is the same. The speeds are also multiplied because this is the air current that is balancing the east-to-west flow at the Equator, and also the rising air over the Equator sinks back down around the 30th parallel. But the circumeferential of the Earth at that latitude is about 1/2 that at the Equator, so the air travels twice as fast.

Think of Jupiter, and the tremendous winds generated there and the different bands going different ways - if there were no land masses the winds on Earth would look similar.

Then there's the depth and underwater terrain - the depth ranges from 3000 to 23000 feet (Mt. Everest is 29000) and is reportedly very rugged with canyons etc. It's one of the least explored parts of the global ocean, because of the conditions.

Comment Re:Flight recorder (Score 1) 491

Most of the electronics in the cockpit - radios especially - are decades-old technology. This is in part because of the overlapping and 'rigorous' FAA and FCC standards. If a single component - a resistor, whatever - is changed, the entire unit has to go through certification all over again, by both agencies. This costs perhaps $10 million, and the total sales of that model radio may be 10,000 units, which means the amortized cost of certification is on the order of $1000 per radio. That is direct cost in advance of manufacturing. Back when I was flying, CB radios that cost under $100 had better reception and better voice quality than $3000 aircraft radios.

Comment Re:So why did Apple and Google toss it? (Score 1) 202

I haven't kept up, but it sez here::

It is widely stated that Quartz "uses PDF" internally (notably by Apple in Quartz's early developer documentation[5]), often by people making comparisons with the Display PostScript technology used in NeXTSTEP and OPENSTEP (of which Mac OS X is a descendant). Quartz's internal imaging model correlates well with the PDF object graph, making it easy to output PDF to multiple devices.[6]

Comment Re:So why did Apple and Google toss it? (Score 3, Interesting) 202

WRT to OSX, there is history. Back in the days of NeXT, Jobs & co. decided to use Display Postscript for a variety of reasons. A few of the reasons: X back then was huge, ungainly and a total beast to work with using the limited memory and cycles available (The NeXTstation used a 25MHz 68000); their team were not ever going to be able to morph X into an object-oriented platform, which NeXT definitely was; Display Postscript was Adobe's new Hotness; the NeXT folks could write drivers for DP that worked with the Texas Instruments signal processor (TM-9900? I forget), which was truly amazingly fast at screen manipulation; and the X architecture didn't fit well with either Display Postscript or the TM-9900.

In 2001 I had a NeXTstation that I added some memory and a bigger disk to. The machine was by then more than 10 years old. For normal workstation duties, it was faster than my brand new desktop machine due entirely to the display architecture. But compiling almost anything on that 25MHz CPU was an overnight task - I had one compile that ran three days.

Comment Coin forgery ... (Score 1) 169

... has been going on for almost as long as coinage itself. One of the advantages of paper money (in addition to weight, lower manufacturing cost, etc.) is that it can be harder to forge. Any shmuck with a press can create coins that are hard to distinguish from the real thing. On a larger scale, one of the big problems today with gold is people hollowing out gold bars and filling them with tungsten, or starting with tungsten and wrapping a small amount of gold. These are indistinguishable from the real thing, for the non-expert and even for experts without the necessary equipment (and suspicion).

IANA bitcoin holder, but having looked into the original Nakamoto paper (which is short and much better than any of the derivatives), and discussed this with people who know, the bitcoin methodology or protocol or whatever is with us to stay, and will be used for a lot of things beyond just digital money. The same methodology will be essential for things like secure confirmed transactions between entities far distant from each other (like space stations, moon colonies, etc. - this happens to be one of my interests); it will be used for 'digital contracts' with its internal scripting system, and perhaps even for guaranteed unique digital identity; and it has the powerful feature that it doesn't depend on any external agency - governments or whatever. So bitcoin itself is having growing pains, and it may or may not survive and grow, but don't believe that the methodology won't be an essential part of many future activities.

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