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Technology Science

Why Airports Rename Runways When the Magnetic Poles Move ( 192

An anonymous reader shares a report: For decades, pilots heading into or out of Wichita Eisenhower National Airport in southeast Kansas have had three runways to choose from: 1L/19R, 1R/19L, and 14/32. Now, at the orders of the FAA, the airport will spend hundreds of thousands of dollars to give itself a makeover. Workers will repaint those huge numbers at the ends of each runway and replace copious signage. Pilots and air traffic controllers will study new reference manuals and approach plates, all updated to reflect an airport whose three runways have been renamed. World, meet 2L/20R, 2R/20L, and 15/33 -- which happen to be the same runways that have been welcoming planes since 1954.

This is not a "What's in a name?" situation. The runways may be the same sweet-smelling stretches of tarmac they've always been, but the world around them has changed. Well, the magnetic fields around the world have changed. The planet's magnetic poles -- the points that compasses recognize as north and south -- are always wandering about. That's a problem, because most runways are named for their magnetic headings. Take Wichita's 14/32. First off, because planes can land or take off from either direction, you can think of it as two runways: 14 and 32. (Pro tip: Pilots say "one-four" and "three-two," not 14 and 32.) If you're looking at a compass, one end is about 140 degrees off of north, counting clockwise. For simplicity's sake, the headings are rounded to the nearest five, and dropped to two digits. So if you're looking down at Wichita Eisenhower, runway 14/32 is the one running from the northwest to the southeast.

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Why Airports Rename Runways When the Magnetic Poles Move

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  • San Jose (Score:5, Interesting)

    by samkass ( 174571 ) on Friday January 19, 2018 @09:24AM (#55959853) Homepage Journal

    The old general aviation runway at San Jose International Airport was runway 29. It was exactly parallel to runways 30R and 30L, they were just built at different times and the pole wandered. The pilots all knew the deal; it seems more confusing to change everything than for pilots to just deal with it.

    • it seems more confusing to change everything

      In aviation things are constantly changing anyway. That's one of the reasons airlines adopted electronic charts on iPads. When you're dealing with something as descriptive as angles the only confusion you could possibly create is by not updating the description to reflect the actual situation.

      Renaming runway Bob to runway Joe creates confusion. Renaming runway 29 to runway 30 when your instruments will say on them 300 degrees when you're on approach does not.

  • For simplicity's sake, the headings are rounded to the nearest five, and dropped to two digits.

    This is not consistent with the names given i.e. '1' or '2' since these have only one digit remaining. Either these names should be '01' or '02' or the method is something even simpler: round to the nearest ten and drop the final zero.

  • by Orne ( 144925 ) on Friday January 19, 2018 @09:38AM (#55959947) Homepage

    Don't index your objects using Natural Keys [] that are a function of slowly changing values. Yes, the naming convention has a value in identifying location as a function of geographic location, but it's a function of a projected geolocation (magnetic field strength) that turns out to move.

    Instead of spending all the money renaming/renumbering the runways, and renumbering them again a couple of decades from now, an engineer would say create a surrogate key that will be constant for all time. Heck, Alpha Beta Gamma, etc would be just as useful in this world of GPS.

    • by Zitchas ( 713512 ) on Friday January 19, 2018 @09:48AM (#55960017) Journal

      There are a *lot* of aircraft out there that don't have GPS systems built in, and even if they are, they are subject to failure. Airports are built to be properly usable to the lowest common denominator of available technology, and in an emergency, the lowest common denominator may well be the basic magnetic compass.

      Emergencies aside, many aircraft (especially home built's, ultralights, and a lot of other non-commercial aircraft) don't bother with things like GPS.

    • 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 approximatel

  • With the advent of GPS and advancements in ground-based technology able to offer redundancy and higher accuracy, is there a reason we're still this concerned about maintaining a naming schema based on compass readings? Are there that many aircraft still in use today that use nothing but a compass for navigation?

    This is kind of like making sure every new car sold comes with a paper map, and every new house comes with a printed copy of the Yellow Pages.

    • by Daa ( 9883 )
      total loss of electrical power is the main reason - lose your generators and you have a limited time on battery only
    • by E-Lad ( 1262 )

      Not all aircraft have GPS navigation, or even electrical systems to support one. Yes, some aircraft lack an alternator and battery - thus they have no electrical system and are not required to have a transponder or other electronic navigation equipment, other than perhaps a battery-powered radio. The engine's spark plugs are fired by magnetos turned by the engine itself (so yes, these types of planes also need to be hand-propped to start, because there's no battery to juice a starter)

      Long story short, GPS o

    • All landings end with a pilot looking out the window and deciding "yeah, that looks about right". The magnetic compass and the data it generates are one piece of a much larger puzzle.

      Yes, I'm aware of things like Category 2 ILS, but they don't do stuff like that unless they absolutely have to.


    • by ceoyoyo ( 59147 )

      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

  • So, one, two, or three plane crashes before someone blames another miscommunication on fog? Just another airport for me to avoid. Love it.

  • I don't get it. One can easily save them the work of renaming the runways (painting and what-not) by inserting a ball bearing in the middle and magnets along the runway! It will automatically align to the magnetic field. Sshhh... some people.

    • No, they just need to move to circular runways. Odd proposal, but could be interesting.

  • by CODiNE ( 27417 ) on Friday January 19, 2018 @10:02AM (#55960151) Homepage

    The Runway Naming System allows pilots to send RNS requests to the local Runway Naming Service which of course run on the local Runway Naming Server (Be aware the same acronym holds several correct definitions). Also I t is appropriate to use the designation "RNS Server", "RNS Service", or "RNS System" even though it may be redundant.

    These local RNS databases are owned by the airports and are synchronized with the root RNS server several layers up in the RNS hierarchy.

    While planes may choose to make RNS requests directly from the root server, for traffic management (bandwidth, not air traffic) they are strongly encouraged to maintain their own local RNS server that caches RNS data from RNS servers at levels lower from the root and geographically local to them. This may be accomplished via RNS Zone Transfers.

    It must also be remember that RNS name updates may take several hours to propagate through the RNS hierarchy and for all RNS servers to update with accurate information. So while pilots may have a local cached copy while in flight from their local RNS server, care must be made to verify the RNS data with the authoritative RNS server while approaching the destination airport.

    As an example the Wichita "Gandalf" runway upon local RNS resolution currently returns 14/32.

    There have been recent reports of RNS spoofing and RNS cache corruption attacks being used, as well as malicious RNS database updates pushed to the RNS root servers and propagated across the RNS network. We are currently working on the next generation of secure RNS Services known as RNSSEC.

    • Funniest thing I've seen on /. in a while. The one day I don't have mod points.
    • by mjwx ( 966435 )
      We could always open it up to a poll... its not like we'd end up with Runway McRunwayface or something.
  • by grub ( 11606 ) <> on Friday January 19, 2018 @10:06AM (#55960181) Homepage Journal

    The molten iron core of Earth is to blame. All we need to do is wait for the magnetic north to be where we want it, then quickly cool the core so it solidifies in place.
  • Even with numbered runways, the occasinal pilot still goofs things up. They're supposed to check their compass against the runway numbers when they're at the takeoff point. Even so, one pilot long ago had his compass set not SIX degrees of magnetic variation, but SIXTY. Instead of landing in London they ended up running out of gas over the Sahara. Another time, a cargo plane took off in the 180 direction from Marseilles, and they crashed into a tall hill miles away.

    • 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
  • by 14erCleaner ( 745600 ) <> on Friday January 19, 2018 @10:46AM (#55960487) Homepage Journal
    Anthropomorphic magnetic pole shifting is a hoax! The poles have always been where they are, and the Fake Liberal Media just wants you to believe that they're moving to advance their left-wing agenda!
    • Correction: you probably meant anthropogenic, not anthropomorphic.

    • Anthropogenic magnetic pole shifting is a hoax! The poles have always been where they are, and the Fake Liberal Media just wants you to believe that they're moving to advance their left-wing agenda!

      Darn right! And if you don't believe it, the proof is that the so-called movement is ALWAYS TO THE LEFT!!!

  • by rossdee ( 243626 ) on Friday January 19, 2018 @10:47AM (#55960495)

    Do they still use magnetic cpmpasses in commecial aviation?

    Y thought it would be based a mountain
      on GPS thwaw days

    They were ysing inertial navigation systems in airliners back in the later 70's

    when Air New Zealand were flying scenic trops to Antarctica
    of course if someone transposed numbers when typing in the waypoints you could still run into

    • by cstacy ( 534252 )

      Do they still use magnetic cpmpasses in commecial aviation?

      At least as a backup, yes. Both the "whiskey" variety and the Hall effect variety.

    • by Shotgun ( 30919 )

      Do they still use magnetic cpmpasses in commecial aviation?

      And commercial aviation is not the only segment that airports are built for.

  • It's not like we don't know how to use true north. TVMDC [], and all that. What with modern avionics, GPS, etc. you'd think they could deal with true north and not have this problem.
  • by supernova87a ( 532540 ) <kepler1@hot m a> on Friday January 19, 2018 @11:10AM (#55960689)
    Hey, I heard that Blockchain is going to solve this problem! Where can I invest?
  • Geologists are concerned that the magnetic poles might soon go through one of their cyclic reversals, flipping north and south. This would result in a number of years where the earth has no net magnetic field.

    If that happens, the FAA will have to direct airports to rename every single runway in this country to "NULL".

    • by Shotgun ( 30919 )

      Nah! Pilot's will just have to fly their planes between the falling skyscrapers on their way to finding the hidden arks that will save the vestiges of the human race. The runway will only need to be realigned after the continents have finished shifting.

    • Geologists are concerned that the magnetic poles might soon go through one of their cyclic reversals, flipping north and south. This would result in a number of years where the earth has no net magnetic field.

      I thought we didn't yet know how long the reversals take?

    • Geologists are concerned

      "concerned" is a little strong. "aware" is how strong it gets for pretty much everyone. That guy on Discovery Channel, Munchkiniko "It's Aliens" Poopants (or whatever his name is) notwithstanding.

      that the magnetic poles might

      "will", not "might"

      soon go through one of their cyclic reversals,

      aperiodic, but fairly frequent. Most people, when told something is cyclical, think "it'll happen every 100,000 years or what ever", then think, "it hasn't happened for 50,000 years, so 50,000 years

  • Thank God for Slashdot where this can be discussed, because the aviation boneheads who came up with the runway naming conventions obviously never thought any of this stuff through! Moreover, none of the reasoning has ever been documented by those (Government, naturally) selfsame boneheads.

  • Reading this aviation stuf and the details in the comments reminds me of messing with AICC e-learning data back in 2002 and trying to convert it into XML or something other more useful. This was an amazing head-trip. You could smell the punchcards and hear the noise of the 60ies batch processors simply by looking at the raw data files. n-dimensional relations were (are) covered across files, data access based on column count, 126 character ASCII (and not a single one more!) more and some other awesome old-s

  • by e70838 ( 976799 ) on Friday January 19, 2018 @12:18PM (#55961257)
    When an airport has two parallel runways, they are often numbered differently in order to "avoid confusion". When landing at CDG, runways 26R and 27L are parallel.
  • Online sources of information are probably updated immediately when the runway numbers are repainted. However, many pilots fly with paper charts and airport directories. Either they fly old planes without modern avionics, or they simply want information that will survive a computer hardware failure. These paper documents expire in a few months and _should_ be replaced after expiration. For at least a few months (possibly longer), pilots rely on old information from paper charts and directories to get run

    • by Daa ( 9883 )
      charts are updated every 14 days , nav databases are updated ever 28 days , you are responsible to have current charts and data

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