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Old 27th Dec 2012, 17:42   #41 (permalink)
 
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Flyburg

It depends on if my route overflies all the NATs or not. Or if my diversion alternate will have me fly from my random route through the NATs for the day. It is a pain but it beats the alternative. If I am on a NAT then I don't plot the other tracks because the contingency procedure will allow me parallel my cleared track until I am below the rest of the NATs and at that point I would continue to my alternate. We also uplink our oceanic clearance and we have CPDLC. I'm not suggesting to anybody that we use the plotter a sole back up to make sure we don't have a GNE, (even though we do plot our position 10 min after a crossing fix to also give us another crosscheck). However its use is invaluable should you have to do a driftdown when on a random route overflying the NATs.
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Old 27th Dec 2012, 19:07   #42 (permalink)
 
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Good pointers,

Like I said, all my flights have been on tracks or well south or north but never across or above! In those cases I don't see the advantage, but in the scenarios described by you and galaxy flyers I do! Thanks
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Old 27th Dec 2012, 19:53   #43 (permalink)
 
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Check your NATS message. You'll see altitudes missing amongst the tracks. Typically the southern or possibly the northernmost track or two. That's for random routes that protrude into the regular tracks.

Southern U.S. to N. Europe or routings from the U.S. to will have random routes that sometimes touch one, or two, of the tracks.

Example - Altitudes 310, 320, 330, 350, 360, 380,

340, 370 and 390 would be used for random routes touching the track. Lower altitudes typically reserved for 767's or long haul 777/A330 flights and higher altitude for lighter 777/A330's.
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Old 27th Dec 2012, 20:30   #44 (permalink)
 
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Have read up on the NAT/MNPS procedures and not wanting to be pedantic but where does it say that when on a random route you have to turn parallel to one of the tracks?

Seriously, our manual gives different instructions and I'm inclined to give somebody at the office a call regarding the conversation in this thread but don't want to make an ass out of myself!
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Old 27th Dec 2012, 21:11   #45 (permalink)
 
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flyburg

That is how it is written in our ops manual that is approved by our POI. International initial and yearly recurrents also state the same thing. Would you really want driftdown perpendicular to the NATs if your route had you overflying the NATs? If you are flying for a 121 carrier then you may never do a random route over the NATs. You will probably be on a track for every crossing or if on a random route well away from the tracks since your aircraft will be too heavy for a climb to FL430. What does your manual say? Is there anything about the driftdown contingency if you above the NATs on a random route? I am curious as to what your company manual wants you to do in that scenario.

Last edited by g450cpt; 27th Dec 2012 at 21:12.
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Old 27th Dec 2012, 22:59   #46 (permalink)
 
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Quote:
Originally Posted by galaxy flyer View Post
Flyburg

There have been cases of jets overflying the track system, having to do an emergency descent and triggering TCAS R/As. Most random routes overflying the NATS will cross them at some point. The requirement is to align the aircraft's track with the nearest organized track, offset and then begin the descent, time permitting. I now ask for flight plans above the NATS to follow the routing, if the planned level is above 410.
Thanks Galaxy Flyer,

A quick but important question.... Do you fly for an airline. Somehow I would think that someone flying thie 777 across the Atlantic is not going to get much changed by telling dispatch to change his routing for reasons stated above.
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Old 27th Dec 2012, 23:45   #47 (permalink)
 
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Jammed Stab

No, I don't fly or an airline, which explains the flexibility I have--corporate GLEX. I have seen plans at F430 and F450 that crossed 4 or 5 tracks--nearly impossible at any one time to orient oneself accurately in relation to a track, offset 15 nm and begin an emergency descent. Anyone overflying the system MUST NOT be a hazard to those on the tracks at lower levels in the case of an emergency. I don't object to random routes, just the difficulty of orientation in the event of a need to descend.

That said, overflying the track system isn't high on the list of B777 pilot's problems.

Spooky

Try Petro (UHPP) to Tahiti sometime, crosses just about every trans-PAC routing!

Last edited by galaxy flyer; 27th Dec 2012 at 23:51.
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Old 29th Dec 2012, 15:38   #48 (permalink)
 
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Quote:
For practical purposes, do you plot all NAT tracks into the plot?
Yep, we plot our random route and the daily tracks using Jeppesen plotting charts, we also change to TRUE heading for the crossing, this was something that doesn't appear to be a common practice in the corporate world (based on my CAE/FSI recurrent training)

As we use Iceland as an enroute alternate, its quite feasible that we will turn and cross more than one track.
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Old 30th Dec 2012, 17:57   #49 (permalink)
 
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Thanks for adding to the discussion!

Just a short note to thank all of you who have added to the discussion I raised in my original post.
One of the pilots who recently attended my International Procedures Recurrent ground school suggested he would request a random route directly above one of the tracks for his crossing from his navigation service provider. That way he knew where the highest level of traffic was relative to his position in the event he had to divert. He felt it was a small price to pay in additional fuel burn to be so much more situationally aware.
In spite of my approximately 100 North Atlantic crossings, I had never thought about this possibility and never discussed this option with other crew members.
What do you think of his suggestion?
Thanks in advance....
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Old 30th Dec 2012, 19:16   #50 (permalink)
 
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I proposed just that! I've only done a coupe of times in the GLEX, depending on routing the penalty can be small or large-ish. Often as not, out crossings are at times when the system is not in use or we're going opposite direction. Crossing several tracks, OPPOSITE direction and having to descend is tough one.

We plot and enter into the FMS, as stored plans, the tracks and our random route.
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Old 3rd Jan 2013, 16:49   #51 (permalink)
 
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it would be interesting to find out what the major airlines are doing on random routes in terms of plotting chart use. Anyone from Emirates, BA, QANTAS, etc.

Last edited by JammedStab; 5th Jan 2013 at 10:19.
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Old 4th Jan 2013, 01:59   #52 (permalink)
 
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Folks,
Re. Qantas, up to the time I retired, the answer was nothing, the last time I saw a plot kept was the last time a flew with a navigator on a B707, and that is a long time ago.
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Old 8th Jan 2013, 02:15   #53 (permalink)
 
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Quote:
Originally Posted by galaxy flyer View Post
Jammed Stab

No, I don't fly or an airline, which explains the flexibility I have--corporate GLEX. I have seen plans at F430 and F450 that crossed 4 or 5 tracks--nearly impossible at any one time to orient oneself accurately in relation to a track, offset 15 nm and begin an emergency descent. Anyone overflying the system MUST NOT be a hazard to those on the tracks at lower levels in the case of an emergency. I don't object to random routes, just the difficulty of orientation in the event of a need to descend.
To be honest with you, I wonder if the risk of a collision with another IFR aircraft during an emergency descent at a randomly chosen time might be less in the above situation in oceanic with no ATC radar contact than in busy airspace under ATC radar contact. With tracks many miles apart as compared to busy airspace there are much less aircraft.

True, in busy airspace ATC can give vectors to other aircraft but that will take time to do and you will have descended several thousand feet before the first ATC instruction has been replied to and as well there may be turboprops in the mid levels as well as aircraft on climb and descent in busy airspace.

However, it does of course enhance situational awareness to have plotted out other tracks on your Oceanic flight.
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Old 8th Jan 2013, 02:25   #54 (permalink)
 
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Jammed Stab

I'd agree with you, wholeheartedly. We've all seen crossing planes where an emer descent would have been interesting, to say the least. One potential problem, under radar control, would be ATC instructions being contradicted by TCAS RAs. And, the radio frequency the descending aircraft was on wouldnt be the one used at the lower levels. At least, over water, the TCAS would be IT!

Last edited by galaxy flyer; 8th Jan 2013 at 02:26.
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Old 8th Jan 2013, 04:23   #55 (permalink)
fdr
 
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Quote:
Another example where the plotting chart is mandatory would be going from Seattle to Tahiti.
Spook2

At the risk of receiving further derision from the author of this comment, please be accurate on your comments as well as your navigation, it is always possible that someone believes what is written in these posts without bothering to cross refer with source references...

If you are a US registered aircraft, then it is a procedure incorporated in AC91.70A. It is not mandatory, per se, it is an FAA AMOC per the AC, which an operator could meet by a procedure developed by the operator and accepted, not approved by the FAA. It is not and never has been a blanket "Mandatory" requirement to various other non FAA operators. If you are expecting that a plotting chart will protect from GNE's, then the history of FAA registered aircraft lost over NAT airspace where there is a mandatory requirement for such plotting is hardly convincing evidence of efficacy.

On the SA side, no argument, particularly with flex tracks, but that is general information and a plot is not necessarily beneficial, and an ERC gives all the info that is needed, with or without chicken scratches. It is only mandatory when it is mandatory, other times merely operator prudence/risk management per their zen and karma status... The SA side is in relation to other tracks, not your own, I would be amazed if your own navigation confidence is enhanced by what is effectively cave paintings in the age of moving maps & GPS. Having opined that, the navigation problem is hardly great other than in details of accuracy... if you cross the ditch on heading & time, you probably are going to hit land on the other side, not within RMP standards, but the likelihood of a plotting chart saving the day when the data came from a company route or other source other than manual entry (flex track etc) is low. In the case of manual entry, the cross reference of track/dist and total distance is more effective than plotting a possibly incorrect position on a parchment for posterity.

Just curious; how long is it going to take any competent or half way competent crew to reconstruct a position on a Jepp ERC from the flight plan if in the middle of the day (night is easier...) if all INS/GPS fall over? I would think that most crews are aware that they were on/off track ahead/behind FPL WPT time/fuel at any given time in the cruise. From that, the current estimated position is readily obtainable, with/without a prayer wheel/Calc/Ipad/Iphone etc.

A procedure that mitigates risk without unintended consequences may be justifiable. A procedure that exists as a hangover of a bygone era that does not have a practical benefit is of questionable gain. Do your chicken scratches make you feel safer or actually be safer? In your procedures, is the chart cross checked from an independent source of data to ensure that no GNE exists? Cross checking is a fundamental necessity, but does not necessarily require a pictorial representation to be accomplished, indeed the double handling of the chart may increase opportunity for error or complacency, dependent on the practice employed.


(QFA carried plotting charts and plotting tools in a kit, for emergency use, and their implementation was proceduralised with particular failure events. NAT/Polar would be different again).

Last edited by fdr; 8th Jan 2013 at 04:54.
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Old 8th Jan 2013, 06:54   #56 (permalink)
 
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Quote:
(QFA carried plotting charts and plotting tools in a kit, for emergency use, and their implementation was proceduralised with particular failure events. NAT/Polar would be different again).
fdr,
Quite so, and I know of no case where the QF crew had to resort to the reversionary nav. envelope in the flight library.
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Old 8th Jan 2013, 09:33   #57 (permalink)
 
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Thanks Guys,

Any retired BA, Cathey Emirates guys etc who did a lot of this stuff care to comment on what their procedures were?

I do plan to use the chart next time I get a random route but that is not very often.
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