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Comment Re:Even with numbered runways..... (Score 1) 192

I know a wellbore surveyor who once recorded the difference between his magnetic sensor's orientation and the steering bend's orientation out by 180 degrees - he read the wrong side of the protractor when torquing the tools together at around 20,000 Nm. For some kilometre of kick-off and around a day's work, they could not work out why they set up the tools to drill in THAT direction, and it drilled in the opposite direction. Then - "light bulb moment", 10 minutes of calculation on the Ouija board (doesn't interfere with the computer), and a very embarrassed conversation with the client. Fortunately, it only cost a few hours of actual operations time, so we covered it up.

Comment Re:As any DBA knows... (Score 1) 192

>

especially the closer to a magnetic pole you are

Oh, come on! One pole is very, very wet, and the other is extremely remote and cold and gets very experienced pilots only.

In this context being within about 30 degrees of (magnetic) latitude of the (magnetic) pole qualifies as "close". We're Nearly 40 degrees from the pole, but I still re-calibrate my compass every couple of years (it has an adjustment for that ; why would you buy a compass that didn't have that?), and there are over 100 square miles of my local navigation area (in several non-contiguous areas) where relying on the compass in 100m visibility conditions could kill you if you got it right. And would also kill you if you got it wrong. So, you use your map, and only use your compass to compare (eg) the angle difference between rock joints and hillside slope.

Comment Re:As any DBA knows... (Score 1) 192

Heck, Alpha Beta Gamma, etc would be just as useful in this world of GPS.

I can't remember the name of the band, but there's a good piece of heavy music that starts with the lyrics "747 coming down in the night / no power, no runway lights". Which is a pretty unlikely situation - both the multiple power systems on the aircraft failing, and those on the ground. But what the fuck? The exact point of having a MAGNETIC compass as a fallback from all other systems is that it requires precisely (not approximately) zero external systems, including not more than zero external power supplies, computational dependencies, or anything else. It's still vulnerable to sabotage - all aircraft are - but not external failure.

Not all aircraft have GPS. Not all commercial aircraft have GPS. Not all GPS systems work all the time. No GPS system is guaranteed to work all the time. So aircraft designs will continue to incorporate magnetic compasses for the foreseeable future, regardless of what you think about the reliability of the systems.

create a surrogate key that will be constant for all time

Thinking as a geologist, which I do, because I am, Neither your geographic location nor orientation is particularly stable - in a mere 10,000 years every airport location in the USA (outside Hawaii, sorry) will have moved around a runway spacing further west (~100m), fucking up anything based on GPS locations.

But the paint won't last anything like that long ; nor will the tarmac. From my local, fairly busy (around 50 flights/ runway/ day) airport, the paint will last some years, and the tarmac will need significant patching about once a decade. Which renders the comments about this being "additional" spending pretty moot. If you've got to relay the tarmac (to repair frost damage and correct for ground settlement - most airbases are on old lakes or river plains, which are not the most stable of soils) every decade or so, then the cost of painting different numbers on the new surfaces, and replacing the signs you had to rip up to get the tarmac-chewers and tarmac-spreaders into place, all become just another part of the cost of maintenance.

Comment How come the "BWM" comment doesn't apply? (Score 1) 158

Just a few lines up in the daily email, there is "BMW's Apple CarPlay Annual Fee is Next-level Gouging" ; so how come this action doesn't also qualify as "next level gouging"?

If you have Slashdot Advertising (I haven't seen that since some years before I started to use NoScript or even AdBlock; I guess there is still some advertising somewhere), then perhaps Amazon are bugger buyers than BMW. Or ... there is some other reason. But it's gouging nonetheless.

I actually brought several things from Amazon last year. Three books, one new, as I recall. Despite being told to make it one delivery, it still required three visits to the post office to collect. Explain to me again the reason for this "Prime" crock?

Comment Re:What? (Score 1) 268

Yup, classic insurance fraud. Many cars in Russia have dash cams for this very phenomenon.

Bollocks, to be polite. The (relatively) high usage of dashcams in Russia is pretty much fuck all to do with insurance claims (since tens of percent of vehicles don't have insurance anyway, compared to singles of percent in more efficiently-regulated countries) and everything to do with avoiding "squeeze" from traffic cops : "Well, citizen, my colleague and I, with guns on our hips, are sure that we saw you jumping that red light, which would mean a 500 Ruble fine and several days off work in court if we start filling out this form. Or we can develop selective amnesia for 100 Ruble. Your choice."

It's by no means unique to Russia, and if anything it has been decreasing over the last few years in response to the frequency of dashcam use and the decrease in on-street corruption in response to Putin's power tightening.

Do AC's even think before writing shit these days?

Comment Re:Problem with outdated information (Score 1) 192

Or a pilot.

His post is a statement of the legal responsibility of a pilot. It may surprise you, but there are professions, even hobbies, where you have actual responsibilities and virtually all of the practitioners take them very seriously.

If you land on the wrong runway because you didn't update your chart, the aviation authority in your location will not be pleased.

Comment Re:Is this that critical anymore? (Score 1) 192

Yes, quite a few aircraft don't have GPS. Flight-rated instruments are very expensive. Also, the electronic widgets fail, usually when you'd really like to have them.

Planes (and boats) are also required to have paper "maps", with the possible exception of some commercial airliners that have managed to get electronic charts certified (not sure if they still need at least one paper backup set).

I'm a qualified celestial navigator. That's with a sextant. I hope it always remains an interesting hobby, but I do know people who have saved their own lives by knowing how to navigate without electricity.

Comment Re:Nope (Score 2) 203

It certainly steepens your descent profile, but the scenario in question was the plane running out of power while circling. And even a couple minutes worth of propulsion at landing makes a world of difference (2% of a 90 minute flight = nearly 2 minutes).

but if it's not enough to do a go-around, it's just not enough.

Seriously, you're demanding go-around capability on emergency, out-of-"fuel" landings?

Comment Re: Nope (Score 3, Informative) 203

You can probably fly pretty much anywhere in Norway and to the capitals of her neighbours in that amount of time. I live in Canada, which is huge, but most of the traffic is on ~1 hour short haul routes.

Personally, I'd wait until I had a few years experience with electric aircraft in a variety of environments and weather conditions before I decreed liquid fuel to be passe.

2040 is still a ways off.

Comment Re:Question (Score 1) 162

Sure it does. If you ask nicely, I'm sure someone would provide you a link. Or you could google it. I think it was even discussed on Slashdot.

He also described the results. The GGP's response was "that's impossible."

"I agree with this" != "this is factually correct"

Not sure how that's relevant, but I agree!

Comment Re:Nope (Score 3, Interesting) 203

The funny thing is, electric aircraft can regenerate on descent. If for some strange reason you "ran out of power" in the air, yes, you'd have to make an emergency landing, but it would be an emergency powered landing. Unlike the unpowered landing a combustion-powered aircraft landing has to make if it runs out of fuel.

Comment Re:Are they sure they don't mean (Score 2) 203

Yes, I prefer my airplanes to be filled with nice safe hydrocarbons. They never burn.

EVs have a lower per-km rate of fires than gasoline cars (various figures suggest around 1/5th the rate). Why would it be any different with aircraft? Furthermore, it's much easier to make components redundant with EVs. Electric motors are light, batteries packs are easy to isolate from each other with no extra weight penalty, etc. In one design NASA has been working on there's a huge number of small props on the wing; they're only run at full power at takeoff, but beyond redundancy, they provide a huge amount of extra lift, greatly reducing takeoff distance. So far, though, they've only built a wing testbed ;)

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