I forgot to specifically say MAGNETIC north pole, but I assumed everyone knew that.

But I got the info from the know-nothings at NASA:
https://www.nasa.gov/topics/earth/fe...eReversal.html

40 miles per year sounded really fast to me, too, given the glacial pace (yswidt) at which geological phenomena typically proceed. But most citations of that rate that I found from the past five years concur. Of course, it's possible that all of them are using the same inaccurate source for that number. But it shouldn't be too hard to find a peer-reviewed paper that cites the rate of movement, and they always rigorously cite their sources. I'll look for Phys. Rev. source because I know the referees would jump all over that if it were inaccurate.

I would expect movement due to nutation (in fact zero nutation is practically impossible), but physical movement even at this slow pace is surprising.

Yeah, we're talking about the magnetic north pole which moves on the order of miles/year (the number isn't constant), which is why runways need to be occasionally re-numbered.

It's not like finding the magnetic pole is hard. All you need is a compass and some time. LOL at peer-reviewed paper. Last year the pole was here. This year the pole is there. How far did it move? Rinse and repeat into the past. That little blurb from NASA even mentions the rate of movement seems to have increased recently.

Perhaps you are confused. No one said the magnetic pole is difficult to find. I didn't say you needed to find a peer-reviewed paper on measuring the movement. I said that finding a paper that cited the rate of movement should be a good benchmark for verifying the accuracy of the cited rate.

The question whether its movement has been measured accurately, how it was measured, and where this has been reported. Referring back to the NASA page simply begs the question of what was the source of the number they cited. I have no reason to doubt it's accuracy, but I am curious about its source.

Here is the info you seek:





From Olsen, N., & Mandea, M. (2007). Will the magnetic north pole move to Siberia. Eos, 88(29), 293-294 (pdf).

The source for these figures is the National Geophysical Data Center. You couldn't have asked at a worse time, though, as However, come tomorrow evening, you should be able to access the info at https://www.ngdc.noaa.gov/geomag/data/poles/NP.xy.

If you want a peer reviewed article, try Mandea, M., and E. Dormy (2003). Asymmetric behavior of magnetic dip poles, Earth Planets Space, 55 , 153–157 (pdf).

For a discussion of how the magnetic north pole is measured, try Newitt, L.R., Chulliat, A. & Orgeval, J.J. (2009). Location of the North Magnetic Pole in April 2007, Earth Planet Space 61: 703-710 (pdf).

Damn Global Warming...

Different form of transport, but what is your read on:

http://www.philly.com/philly/busines...ash-order.html

When the NTSB rules the driver in the clear.

Cool. Thanks.

So are runways numbered based on magnetic North rather than GPS North then?

Yes.

WRONG


The magnetic north pole also has a daily movement due to the sun. It is never at its mean position and can be as far as 80km (50 miles) away from it.

I don't think that bit of info makes p4b wrong.

While my post does not invalidate his first statement, that you could find the magnetic north pole with just a compass and some time (though even that is impossible, since when you're near the north pole the needle will want to point down, so if you have your compass even slightly tilted, it will just point to the lowest part), it does invalidate his statement that you can measure the pole's yearly movement by comparing two measurements taken a year apart.

Wat?

So if this year it's 40 miles north of where it was last year, it didn't move 40 miles northward?

Yesterday at my previous home field, Teterboro, NJ, a Learjet 35 crashed while on a short visual final approach to runway 1 as he was circling to land. Winds were from the north at 16 gusting to 32 with wind shear previously reported by a departing a/c.

http://www.nbcnewyork.com/news/local...422480734.html

I know this investigation is gonna to take a while, but according to some of the pilot witnesses on the ground, it seems the aircraft made a hard bank and ended up sideways before his wings stalled and he nose dived into the ground and disintegrated.

As soon as I heard the live tower feed (below), and after I heard the local controller had to tell him to start his turn, It sounds like he either miss judged the approach, was lining up for runway 6 instead of 1, or didn't make the corrections for the wind which blew him further away while in a turn.

https://youtu.be/yOr3rQn1qHc


This, in my opinion, is probably going to be pilot error, and an example to other pilots when to initiate a go-around, rather than try to over correct an unforgiving aircraft. Do you agree with my preliminary conclusion so far W0X0F?

RIP to the two pilots.

correct link

https://youtu.be/QwCka8KtcV8

Does watching this video make you laugh, induce panic, or something in between?



Also, unless I've missed it somewhere, describe your worst interaction with an ATC.

http://edition.cnn.com/2017/05/20/us...ion/index.html

What kind of rules apply to traffic on the ground and who gives way to whom? Are the ground vehicles also controlled by ground control? Or just required to stay out of the way of aircraft?

My first guess, based on the very limited information, is that they encountered windshear and attempted to arrest an unexpected descent rate by raising the nose (trading airspeed for climb). The winds were strong, but almost right down the runway, so there should have been no overshoot issue turning final (which can lead some pilots into steepening their turn, increasing load factor and resulting in potential stall/spin scenarios).

Your guess that he may have first fixated on runway 6 (evidenced by the controller's remark), would have been a self-induced overshoot. It would be very unfortunate to encounter windshear at the same time you steepened your bank. The Lear is a high performance bizjet, though I don't think the current models (such as the 35) are anywhere nearly as squirrelly as the early models, and increased load factor coupled with lots of lift in windshear would be a bad situation.

NTSB report to follow... (6 months?)

Makes me laugh. I like the IFR clearances including squawk codes of 7500 (hijacking) and 7600 (lost communication).


Worst interaction with ATC? Honestly, I've always found ATC to be helpful.

The most frustrating situations have been when we're in the approach phase to a busy airport with severe weather in the area and, due to the high traffic load, we can't get a word in with the controller advising of our need to maneuver around weather. The controller is saturated and you can hear the stress level in their transmissions. Pilots and the controller are stepping on each other's transmissions and some pilots inevitably have to turn without an explicit clearance, advising the controller when they're able. Just a high stress situation for everyone.

99.9% chance it was the truck's fault.

Generally speaking, manoeuvring areas (taxiways, runways, other "operational" areas) are controlled by the ground controller, while the ramp/apron is uncontrolled - meaning the aircraft or vehicles are responsible for not hitting each other. However, vehicles are required to stay clear of all aircraft, and have very restrictive speed limits to ensure this doesn't happen.

That being said, anyone operating a vehicle at the airport (other than one being instructed "to follow" a designated lead vehicle) has training to drive on the field. This training includes study (airfield configuration and procedures) and practice (driving and radio comms). Unfortunately, many drivers don't have the same dedication as controllers and pilots do towards safety, and don't really listen on the radio.

As both a ground controller and airport controller, I've seen multiple instances of vehicles assuming a clearance is for them and crossing an active runway, or just completely ignoring the "hold short" line (a stop line to ensure aircraft or vehicles don't enter a runway).

That's a lot of words to say the aircraft almost certainly had the right of way.

The ATC ground controller issues clearances for any airplane or ground vehicle to taxi on a taxiway or runway. The controller will take care of right of way issues with their clearance (e.g. "Hold short of Victor" or "Give way to the United 737 at Gulf, then proceed on Zulu to runway 22 Right"). But it's always our ultimate responsibility to not run into something. If I see a potential conflict looming, I'll just ask the controller who should give way. There are no set "right of way" rules on the taxiway as there are, say, with two cars approaching an intersection.

There are areas of the airport, such as the ramp area where aircraft park, that are designated as "non movement" areas, which are usually under the control of a non-ATC entity, but at smaller airports might be completely uncontrolled. The ramp controller issues pushback clearances and clearance to enter the ramp and proceed to a gate. At Dulles airport, this is handled by MWAA (Metropolitan Washington Airport Authority). At JFK, Delta controls one of the ramps. Other ramps have different non-ATC ramp controllers. Each ramp has a discrete radio frequency (obv).

Ground traffic (baggage carts, tugs, fuel trucks, etc) move around the airport on their own, without clearance unless they are going on a taxiway or across a runway, in which case they need clearance from Ground Control. On the ramp, they can drive wherever they want, just taking care to avoid aircraft (and heeding any marshallers giving them the hold sign while supervising a pushback).

There are lines painted on the ground for two way traffic around the airport and in these lanes, ground vehicles follows typical rules of the road with respect to other ground vehicles, but always give way to airplanes. This is typically seen on the ramp entry/exit points, which are part of a taxiway. More than one pilot has had to suddenly stop short in this area as a fuel trick or baggage cart plays chicken with the airplane and scoots across the access point. It's a pretty serious breach of the rules and pilots aren't hesitant to note the vehicle number and report it to the tower.

In the ramp area, there are often lines painted marking the "footprint" of the aircraft at the gate and all the ramp personnel know not to park inside these boundaries, and pilots won't proceed into the gate if they see equipment inside those lines.

While a plane is parked, care is taken to stay clear of the plane and this is where a lot of inadvertent damage occurs. Many airlines require ramp personnel to place pylons or barriers once an airplane has been parked to help avoid collisions.

When I was at United Express, we had an instance of a ground vehicle plowing into the wing of an RJ while it was taxiing. It was one of our recently delivered planes and did severe damage. This was just a case of a driver not paying attention. She was speeding and it was at night. If you see a situation like what's shown in your picture, it's always the fault of the ground vehicle operator.

President just announced a privatization of ATC.

That's as bad an idea as I think it is, right?