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Magnetic Pole Shift Affects Tampa Airport
RFSSystems writes "I thought this was an amazing and rather rare phenomenon and wanted to share. 'The airport has closed its primary runway until Jan. 13 to repaint the numeric designators at each end and change taxiway signage to account for the shift in location of the Earth's magnetic north pole.' It appears that the shifting poles have begun to affect air travel in a somewhat modest way. Could this also be the explanation for the falling/dead birds this week?" I hope the gradualists are right, but scenarios for rapid magnetic pole shift are fun to think about.
The airport I work at has a second set of signage from when the gradual shift occurs in cycles, making for a 10 degree change in the direction of the runway. Ie, here it will be runway 10-28 becoming runway 09-27. Has nothing to do with birds, happens every decade or so. Ten years after that, itll be back to what it is now.
if we'll see a similar phenomenon with the bee population as we start moving into the warmer months ahead. Perhaps it's not just a cell phone boom that was to blame last year...
8==8 Bones 8==8
Changing magnetic deviation due to movement of the magnetic pole goes on all the time. Runways are numbered according to their magnetic heading, plus or minus five degrees, and they have to keep them up to date, is all.
Two seconds of googling found this comment thread discussing a different runway-renumbering from July of 2009.
Obviously not enough airplane geeks around here...
2*3*3*3*3*11*251
The movements of magnetic north have, on many prior occasions, caused airports to have to redesignate their runways. Since it requires updating of all the charts that aircraft are required to carry (not to mention signage on the ground), it's often deferred as long as possible. Tampa doing this isn't really that significant, although I admit that it's kind of neat in a visual-manifestation-of-invisible-phenomenon kind of way.
Wikipedia subsection on the subject.
This has happened before, and it'll happen again.
Airport runway numbers are based off their magnetic headings with the last zero removed. So a runway that runs due south/north is 18/36 (i.e., it faces 180 degrees south and 360 degrees north - 0 isn't used). A runway that runs due east/west is 9/27. And so on. When there are parallel runways facing the same direction, the L, C, and R designations are used. A pair for parallel east/west runways are 9R/27L and 9L/27R.
So as the pole drifts this sometimes causes runways to have be renumbered. One previous example is Reagan-National airport in Washington, D.C., where runways 1/19 and 4/22 were originally 18/36 and 3/21.
In 3010, the potatoes triumphed
Your "rapid magnetic pole shift" link is to an article about the (fairly ridiculous) rapid shift of the axis of rotation of the planet rather than the magnetic pole. The two really should not be confused.
Its a change in magnetic variation (deviation is the discrepency in a magnetic compass due to its electromagnitic surroundings). Happens all the time. It's only when the change exceeds certain tollerances that they change the runway numbers. And those tollerances all depend on when that particular airport was last numbered.
The birds got confused by the discrepancy between runway numbers and magnetic north, couldn't figure out where to land, ran out of fuel, and crashed?
No, that was not the magnetic pole shifting. Stop watching movies like 'The Core.'
I hate this site sometimes, largely because I'm about to be blasted for saying this... but...
The Core is only partially terrible science.
PLEASE DON'T MURDER ME. Let me speak...
The magnetic field over the earth DOES in fact shift around, and it is, at least some of the time, due to changes in the core. Also it is assumed to cause bad things to happen.
So the premise of the film, being that the Earth's core is messed up and is causing us a bad time of it, isn't really all that flawed.
Now the laser-worm with the bombs and all that, THAT is crap. But birds falling from the sky can and does already happen due to magnetism. Check out pigeon races and how they have to plan them around these fluctuations.
Friends don't give friends chlamydia. -- The Pole.
The enemies of Democracy are
"Nuke-lee-ar" is still three syllables. You don't say "new-clear", do you?
Sure you do! At the heart of every atom, you find its newklus.
~Idarubicin
Build the runways on giant wheeled platforms on rails that can be reoriented to the magnetic field so that you never need alter the runways numbers.
Because not every plane has a GPS or INS. (Certified) GPS equipment is still new and expensive for airplanes. INS is very large and heavy, and only used on large commercial jets.
And perhaps most importantly, a compass always works. If everything else fails, you still have that as a backup.
The compass requires no electrical power.
I fly a Cessna 172S equipped with a Garmin G1000. It's a glass cockpit that makes life much, much easier, but I still have a few analog instruments: compass, attitude indicator, airspeed indicator, and altimeter. All of them function on principles in place on aircraft for many decades now, and provide a layer of reliability in case just about everything goes wrong. I can lose the entire electrical system and still be able to fly to the best landing site available, because the compass is based on the Earth's magnetic field, the attitude indicator is based on a vacuum-driven gyro (the vacuum pump is mechanical and run by the engine), the altimeter is based on the static air pressure, and the airspeed indicator is based on both the pitot tube and the static air pressure. (The engine spark is provided by magnetos that will keep providing spark as long as the engine is turning - no battery required.)
There are complications when flying at night, but that's why I carry a hand-held navcom radio and a couple of flashlights with me in my flight bag.
You can never go home again... but I guess you can shop there.
Because they offer the best bang for the buck. Because pilots are trained to use them. Because they work. Because aviation is totally anal about "if it ain't broke, don't fix it". This is A Good Thing.
I'm learning to fly in Piper Cherokees, and I have a magnetic compass and gyroscopic heading indicator at my disposal. Both are accurate, but both have idiosyncrasies.
The magnetic compass is subject to errors when accelerating or decelerating on east/west courses. It also misbehaves when turning to/from north or south. The heading indicator slowly drifts as Earth rotates underneath it. On long flights you have to periodically re-set the heading indicator.
The pre-takeoff checklist includes setting the heading indicator to the magnetic compass, and verifying that both read correctly when you pull on to the runway. In the future Runway 01 (13 degrees) will become Runway 36 or Runway 02.
...laura
Happened in Falköping, Sweden to:
http://gfx2.aftonbladet-cdn.se/multimedia/dynamic/01365/05s21-pippidea-809_1365286l.jpg
But it was just a retarded truck driver who had drove them over.
People started to talk about fish, bees and some idiots about electromagnetic waves from phone antennas, UFOs, (US) government supposedly spraying barium, strontium and so on into the atmosphere showing pictures of planes with regular trails and saying "OMG OMG OMG!" ... Oh well. And the bees (actually) died from some Monsanto (?) poisoning which also happened to kill bees, which was known.
Funny how everything bad comes from Monsanto but anyway :)
I learned to fly at Elmendorf AFB, in Anchorage, Alaska back in the early '90s. When I first started flying at the Elmendorf Aero Club, the main runway was runway 05. A few years later, it was redesignated runway 06. Merrill Field, a civilian airport just a couple of miles away, also had to change the primary designation from 06 to 07 at about the same time.
The magnetic poles shift with time, eventually by a significant factor. Since runways are designated by magnetic heading (for example, Elmendorf's runway 06 means the runway is pointed roughly to 60 degrees, and Anchorage International Airport's runway 14 is pointed roughly to 140 degrees), every so often airport management has to redesignate the runways to match the approximate magnetic heading with which the runways are aligned. It's no big deal, and has been happening for as long as there have been runways. All of the speculation at the end of TFS about "...shifting poles finally starting to affect air travel..." and "falling birds" is alarmist nonsense.
MCSE? No, sir...I don't do Windows. Yes, I am an idealist. What's your point?
I was flying into Des Moines airport shortly after they had to re-number the runways here. The controller cleared me to land on 31 Right, and I asked why it had changed, He explained about the pole shift, and I asked him if the instersecting runway (23) had changed? No it had stayed the same. I asked "Does that mean they will eventuallly be paralell?" (long silence) "We'll have to get back to you on that"
304 degrees changes to 305 degrees, the runway designation changes from 30 to 31. Meanwhile 231 degrees changes to 232 degrees, it remains Runway 23. I expect the controller had other things to do and trusted you to check /. for the answer one day.
Quidnam Latine loqui modo coepi?
Yup. The compass is one of the few instruments required in every aircraft in the US. Give me a tachometer, a compass, and an altimeter and I can navigate an airplane across the US.
GPS just recently came into the cockpit and the devices are expensive. People should realize that these are aviation instruments, so they need to be certified and are in turn expensive.
INS isn't in every aircraft simply because not every aircraft needs to be instrument-rated. Some people, like myself currently, only fly in VFR conditions. Removing these expensive instruments saves money, as you said.
Want to see a pilot bitch? Tell him he needs to buy something. For a great example of this search Google for the term "ADB-S requirement" and see the pilots moan about this new requirement. I should know, I'm one of them :D
Tiger Blooded Bi-Winning Machine
Huh, I have a military fighter aircraft grade INS with a 2 hour battery backup packed into a 3U rackmount box right next to me that indicates it weighs 17lbs. Yea, it was expensive (low 5-figures). So are aircraft.
Many aircraft cost in the mid-to-high 5-figures. Adding 10-20% to a private plane's cost, or double that if you want redundancy, seems excessive when the only benefit is some geek's sense of correctness. Adding 6U worth of rack equipment isn't exactly easy either - space can be quite tight up there as it is.
You're special forces then? That's great! I just love your olympics!
And just remember that the inconvenience for the airport every 10 years won't put any lifes in risk. The inconvenience for the pilots every time they land will put several (every crew member and passenger) lifes at risk.
Also, I don't get the GP. The pilots like it the way it is, the airports aren't complaining either and nobody else ever see the numbers (except by curiosity). What is his problem with the current convention?
Rethinking email
I'm Canadian you insensitve clod. We use True North (coincidentally Strong and Free) for runway designations and thus are immune to drifting runway numbers. Let's hope desperately that the Earth's spin axis doesn't start moving!
Strangely... as the years go by, I AM feeling a growing desire to learn the Cyrillic alphabet.
Flight is not generally as precise as many people think. Extreme precision is required on take-off and landing, and is not as critical in most other phases. In fact, intrument error traditionally provided a certain margin of safety in flight. Charts have for years now contained a warning regarding waypoints:
Basically, the planes fly so precisely using GPS coordinates, and especially when using GPS-based autopilots, that there's an increased proximity danger at waypoints, which may include airports.
Flying purely by hand, or even on instruments that have known error ranges, there is a safety margin because of the slop. Flying purely by precision instruments improves efficiency and some safety factors, but requires knowledge of the limitations as well.
You can never go home again... but I guess you can shop there.