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rsiano
25th Dec 2012, 15:51
I referred to the Federal Aviation Administrations's Advisory Circular 91.70a to discover we are required to maintain a plotting chart where the route segment between the operational service volume of International Civil Aviation Organization standard ground-based NAVAIDS exceeds 725 nautical miles for turbojet aircraft and 450 nautical miles for turboprop aircraft on page 28. On page 29 there is a statement that says "Plotting Procedures for Special Conditions. The Administrator requires plotting procedures for routes of shorter duration that transit airspace where special conditions exist such as reduced lateral and vertical separation standards, high density traffic, proximity, or potentially hostile border areas."

It does not suggest a place where I can find a listing of such routes. Can any of you suggest where I might find this list?
Thanks!

Spooky 2
25th Dec 2012, 16:50
I don't have answer for the routing question. If you give me an email address I can pass along an email contact for the FAA Intl Ops Inspector out in SFO and perhaps he can forward an answer. I also would like to know where these specific routes are located. NCA is the only one I can think of that might qualify at this moment.

Keep in mind that the AC is advisory only and it may not be as definitive as one would think. The ATS routes between the mainland and HNL come to mind. I don't think many carriers are using a plotting chart on these routes. They do keep one handy in the event of a re route or other off track diversion, but routine plotting I don't think so.

I'm a real advocate of plotting, so please don't assume that I'm looking for excuses to eliminate this one last chance to detect a GNE before it's to late.

JammedStab
26th Dec 2012, 00:37
I referred to the Federal Aviation Administrations's Advisory Circular 91.70a to discover we are required to maintain a plotting chart where the route segment between the operational service volume of International Civil Aviation Organization standard ground-based NAVAIDS exceeds 725 nautical miles for turbojet aircraft and 450 nautical miles for turboprop aircraft on page 28. On page 29 there is a statement that says "Plotting Procedures for Special Conditions. The Administrator requires plotting procedures for routes of shorter duration that transit airspace where special conditions exist such as reduced lateral and vertical separation standards, high density traffic, proximity, or potentially hostile border areas."

It does not suggest a place where I can find a listing of such routes. Can any of you suggest where I might find this list?
Thanks!
Dick Siano
FlightSafety International
Pilot Instructor

Doesn't this mean any route greater than 725 miles whether published or not(and therefore there would be no published list).

I am very new to this long haul stuff, and I have to admit, after several oceanic crossings, we have not used a plotting chart. Most flights were on published routes but one was on a random route of many lat/long coordiates. We do a route check(paper flight plan as filed with ATC vs ACARS uplinked flight plan on the route page) prior to departure from an ACARS uplinked flight plan and check total distance only which can be off by several miles due whether or not the planned approach was entered.

Perhaps I should know better, but do most airline folks out there crossing oceans pull out a plotting chart and use it. And is this route check sufficient in your opinion.

Thanks

Spooky 2
26th Dec 2012, 00:45
JammmedStab don't know who your flying for but find it hard to believe that your operations support the notion of non compliance with regard to the post position plot on a random route. Please familairize yourself with this small detail and use it so as to keep your ass out of the meat grinder. It's not just a matter of your position that you could be endangering but multiple other aircraft operations as well along your route of flight.:}

I feel certain that if you did a search on this website you would find several good posts regading this subject as it has been discussed in great detail in the past.

Are your aircraft CPDLC ADSC equipped?

JammedStab
26th Dec 2012, 01:15
JammmedStab don't know who your flying for but find it hard to believe that your operations support the notion of non compliance with regard to the post position plot on a random route. Please familairize yourself with this small detail and use it so as to keep your ass out of the meat grinder. It's not just a matter of your position that you could be endangering but multiple other aircraft operations as well along your route of flight.:}



I will look further into it. So far I have only done one random route crossing. Perhaps it was just that particular instructor's way.

Spooky 2
26th Dec 2012, 02:04
Let us know how that works out for you. No plotting while flying in the NAT is simply unacceptable and if you were under EASA or FAA oversight, I suspect that you would get a very serious repermand.:E

Having said all of this you do need access to a plotting chart for the area of operations. Hopefully they are available....

JammedStab
26th Dec 2012, 02:43
Yes, there was one onboard but not used. Perhaps an individual instructor thing.

Will ask other instructors.

I did notice that you said the associated AC about plotting charts is advisory only, now you say "No plotting while flying in the NAT is simply unacceptable and if you were under EASA or FAA oversight, I suspect that you would get a very serious repermand". As I am new to this stuff can you please clarify.

Spooky 2
26th Dec 2012, 03:48
Sorry about the comfusion. The NAT is unique so plotting is a requirement since it is basically a random route twice a day. I have the 2012 edition in a PDF format and would be happy to send it to you if you provided an email address via a PM. :ok: I have a few other items that you may like to read as well.

Chapter Eight talks about the plotting requiremnts in the NAT.

JammedStab
26th Dec 2012, 04:07
Thanks, I am a Pacific guy. Same thing I assume.

Spooky 2
26th Dec 2012, 15:22
I'm missing your point and this subject is simply to large to continue with in this format. Does your airline have anything that resembles an International procedres course? Happy to forward you some materials regarding this and many other international procedures as it sounds like you may benefit form some self induced education on this.

Desert185
26th Dec 2012, 18:24
JammedStab

Thanks, I am a Pacific guy. Same thing I assume.

I flew the Pacific for years. Plotted every long range, overwater leg. To not do it and need it, would (at the very least) be embarrassing. :*

I actually lost two LTN 92's out of three (and my ADI/HSI) one night from NRT-ANC.

Plotting keeps you in the loop. :cool:

Phil Squares
26th Dec 2012, 18:55
Having flown both the Pacific and the Atlantic for over 20 years on the 747 Classic and the -400, the plotting exercise was the same in both aircraft. Granted the 400 is much more reliable than the classic with Delcos and Litton 92s, throw in GPS updating and any major system failure is fairly remote. However, if anyone has my luck, the first time it's not done is the time you will really need it.

Have flown for three different carriers, and all of them the SOPs were all the same. Plotting was mandatory.

westhawk
26th Dec 2012, 20:13
The international procedures courses I attended (Scott IPC) and did online recurrents with (ATI) both stipulated that the plotting charts were part of the master document required to be retained (for 6 months?) following any flight in international oceanic airspace. IIRC the FARs require US operators to follow the ICAO annex 2 procedures. I would expect that other ICAO signatories have similar language in their own aviation regulations.

The potential practical benefit of plotting the actual track of the aircraft on the basis of position checking should be apparent: The position checks plotted on the chart should agree with the the pre-plotted track. This is not only a GNE detection measure but along with the heading and GS info recorded on the flight log and forecast winds is the only remaining navigational basis upon which to continue the flight by dead-reckoning should a loss of navigational sensors or computation capability (GPS/IRS/FMS) occur. As unlikely as total navigation capability loss might seem in most aircraft today, the antiquated old plotting chart is considered to be the last line of defense.

So during the relatively small number of crossings I've done, we completed the logs and plotted our position as required by company procedures then turned them in with the rest of the trip paperwork to be filed away in a box somewhere. I sometimes wonder how close we could have come to hitting our coast-in fix if we'd had to rely on dead reckoning, especially in case of a contingency deviation from planned track or a diversion to an enroute alternate. Bad days are always possible!

fdr
26th Dec 2012, 22:41
Annex 2 is Rules of the Air.... which while being of great benefit to the management of aviation in general are not germaine to the question whether a plotting chart is necessary.

While the FAA may propose a procedure which is great for FAA aircraft to follow, unless it is an operating requirement of a particular airspace and promulgated as such, it is not binding on any other party.

A foreign aircraft operating into the US is obliged to comply with Part 91, and 129. Part 129 requires the aircraft to be also operated under OpSpecs as approved by the FAA, which does not include a plotting requirement.

Having crossed the ditch on a routine basis for some 30 years, I can state I haven't seen a plotting chart used, once. Polar, different deal, and I don't object to that, except for the lack of understanding of what is being done anyway by those furiously plotting positions per policy, and then burying the chart under dinner plates. NAT... different deal, no issue, specified procedure. With the initial introduction of Pacific flex tracks, there certainly was a case for plotting the track out, but it was not a specific requirement. (Polar tracks I-IV however has had MIL radar coverage since at least 26 Oct 1962... :| , Antarctic slightly less coverage).

If I appear blunt on this matter perhaps it stems from watching navigators furiously working on charts using data sources that were occasionally just awful, such as single ASN-42's, dopplers etc.

On the assumption of any reasonable level of cognition, above somnambulism, it is still difficult to see what the immediate gain is for a plot vs other means of cross checking of reasonableness. A check of total distances, L/L or track/distances for each leg between the FMC/FMCGS and the flight plan is sufficient to give a safeguard for gross procedural error and a basis for navigation reversion in the case of multiple system losses dumping you into a life of no GPS or INS, just the compass and clock.

westhawk
27th Dec 2012, 04:45
Yes, fdr, annex 2. I only mentioned annex 2 because FAR 91.703 does. However due my inadequate adeptness at negotiating the rabbit warren of document construction that is ICAO, I am unable to locate the specific requirement for a master document even though my training materials quote ICAO annex 2 as the authoritative source. As to the matter of the plotting chart, the company manual at my last outfit requires it's use while the NAT/MNPS manual only recommends the use of a plotting chart in addition to the required master document. Accordingly I'll concede your point that the plotting chart is NOT required unless it can be shown by some other means that it is.

As to the practical usefulness of a plotting chart, that is strictly a matter of opinion and I'll presume yours to hold greater validity than my own in light of your obviously greater experience in ocean crossings. (as I previously stated I've only done a few crossings) However I personally believe that the chart (properly annotated with position/winds checks) would be of significant assistance in executing the remainder of the flight following NAV loss to a fairly high degree of accuracy. Perhaps even accurately enough to remain within the allotted lateral tolerance. Yes the same thing can be done using only the flight log but the method of plotting the track is perhaps more visually intuitive than the numbers alone. Since I don't prefer to sleep, read magazines or do crosswords while flying, marking a plotting chart isn't any extra trouble at all!

In any case the extremely remote possibility of finding oneself down to compass and clock these days probably renders this discussion entirely academic. But then cynicism just comes to me naturally...

despegue
27th Dec 2012, 07:40
I simply can not believe that there are collegues flying oceanic operations without plotting. Are you That lazy, are you that clueless about one of the most basic Pilot navigation practices?! No wonder that some consider us glorified busdrivers if you do not even know how to properly do chartwork.:=:mad::ugh:

noneya
27th Dec 2012, 07:50
Take a class! Learn how to cross the ocean correctly! Some of you guys scare me that we share the same airspace! :mad:

Try looking up, or google it if your company does not have a copy, AC91-70A

http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC%2091-70A.pdf

It will read just like this!!

3-6.
POSITION PLOTTING.
a.
Plotting and Systematic Cross-Checking of Navigation Information. During all phases of flight in Class II navigation, each operator’s long-range navigation program (LRNP) will require the standardized application of disciplined, systematic cross-checking of navigation information.
(1)
Plotting Procedures Impact. Plotting procedures have had a significant impact on the reduction of gross navigation errors (GNE). There is a requirement to plot the route of flight on a plotting chart and to plot the computer position approximately 10 minutes after waypoint passage. This may or may not require plotting, depending upon the distance between the standard ICAO ground-based NAVAIDs. This applies to all operators.
(2)
Turbojet Operations. All turbojet operations, where the route segment between the operational service volume of ICAO standard ground-based NAVAIDs exceeds 725 NM, require plotting procedures.
(3)
Turboprop Operations. All turboprop operations, where the route segment between the operational service volume of ICAO standard ground-based NAVAIDs exceeds 450 NM, require plotting procedures.

westhawk
27th Dec 2012, 09:07
Thank you for posting the link to AC 91-70A noneya.

I was hoping to find a regulatory document requiring the use of a plotting chart to better make my point regarding the need to do so. Unfortunately I was unsuccessful in finding it and had to admit that I was at a loss to quote a regulatory requirement. As far as I am concerned personally, the company manual requirement is reason enough for me although I would still use the plotting chart even on an empty repositioning flight in a privately operated aircraft not on an operating certificate just because it makes sense to do so. The MNPS manual recommends the use of a plotting chart to supplement the master document (flight log) and that's good enough reason for me too until I know better.

In any case, obtaining MNPS approval from the FAA is aided significantly by following the "advise" contained within several ACs. On the operational side, pilots and operators benefit greatly by the fact that several highly regarded international procedures courses are offered which gather regulatory and procedural data from a great many different sources and present them as a single package to their clientele for what amounts to a reasonable fee when you consider the alternative.

My experience is strictly parts 91 and 135 bizjet ops so I don't know whether certain part 121 ops employ some alternative means in lieu of using a plotting chart. It just seems to me unlikely that they simply decided it's not necessary. Besides, what a nice thing it is to see your various contingency ETPs right there on the chart (as you plot your progress) along with what you are expected to do (side panel on the brand we used) in each of those contingency cases though. Thank you Cap'n Jeppy and other fine chart makers!

JammedStab
27th Dec 2012, 09:21
Seeing as I don't really have experience at this and am trying to learn more....perhaps a detailed response to this earlier statement by another poster

" it is still difficult to see what the immediate gain is for a plot vs other means of cross checking of reasonableness. A check of total distances, L/L or track/distances for each leg between the FMC/FMCGS and the flight plan is sufficient to give a safeguard for gross procedural error and a basis for navigation reversion in the case of multiple system losses dumping you into a life of no GPS or INS, just the compass and clock."

Phil Squares
27th Dec 2012, 09:29
One simple reason I have done it is because the requirement was made mandatory in our SOP. I know for a fact, the first carrier where I flew the 400 was instrumental in ensuring the long range nav procedures were carried over from the classic to the 400.

Jammed Stab raises the issue of checking distance, L/L and/or track distances for a crosscheck. I can not tell you how many times I have seen the wrong L/L entered and the distance and track match what the correct route should have been. In addition, when you have a re-route it's not a big deal to plot it out. I might be a simpleton, but I believe one picture is worth a thousand pictures.

Let's be realistic, in this day of CPDLC/ADSB, taking a minute to do a quick plot is not going to upset the work load. It might upset your power nap, but that's about it......

oceancrosser
27th Dec 2012, 09:44
The ICAO MNPS manual for the NAT MNPS (Minimum Navigation Performance Specification) can be found here

Documents (http://www.paris.icao.int/documents_open/files.php?subcategory_id=108)

Search the document for "plotting". Several references. I have been plying the Atlantic for 28 years, but only made a few Pacific crossings. Same procedures used IIRC.

noneya
27th Dec 2012, 09:52
With most of us pilots having dyslexia (5 out of 3 of us have it), are you really just going to trust your FMS typing abilities? How do you know that you are on track without doing a 10 minute past plot? Plotting and checking is what keeps us from having GNE's.

When the regulating agency comes looking for you after you have a GNE, what are you going to say "I am to good to follow the reg's or its my FMS's fault" And when they ask to see your Master Docs (FLT Plan, WX, Notams, Plotting Charts, ets.) that you are required to keep on file for 6 months, what are you going to say?

Come on guys how long does it possibly take? :ugh:

LeadSled
27th Dec 2012, 10:12
While the FAA may propose a procedure which is great for FAA aircraft to follow, unless it is an operating requirement of a particular airspace and promulgated as such, it is not binding on any other party.
A foreign aircraft operating into the US is obliged to comply with Part 91, and 129. Part 129 requires the aircraft to be also operated under OpSpecs as approved by the FAA, which does not include a plotting requirement.Folks,
fdr has it right.
I spent my whole career crossing large amounts of ocean, the last time I saw a plotting chart in my home airline was the last time I saw a navigator, and we had a navigator because it was before INS. Once we got INS on the 707 (yes!, that long ago), the nav. went on the oceanic routes. With doppler, they had long gone on the over land routes.

Sure, we carried a plotting chart in the reversionary nav folder, but only to be used from the last known accurate position, in the event of a total INS failure. In some 30 post navigator years, I never had occasion to open said folder, and I don't recall anybody else in the company having to, either. That covered millions of flight hours.

The only time I did regularly keep a plot, was several years with another carrier, trans Atlantic, and only then for my own protection, because the equipment we were using was such crap (compared to my long term employer), not because there was a regulatory requirement.

JammedStab
27th Dec 2012, 11:47
With most of us pilots having dyslexia (5 out of 3 of us have it), are you really just going to trust your FMS typing abilities? How do you know that you are on track without doing a 10 minute past plot? Plotting and checking is what keeps us from having GNE's.



I should mention that our random route flight plan along with all our other flight plans are downloaded into our FMC's by ACARS, so they are not manually entered into the FMC's by typing. However, even if manually entered, can they just be compared with distance and bearing comparison to the paper flight plan?

GuilhasXXI
27th Dec 2012, 11:53
wow I thought the plotter wasn´t used in commercial aviation anymore :ooh:

g450cpt
27th Dec 2012, 13:12
Consider this. You are flying a random route that is over, near, or parallel to one of the days NAT tracks. You haven't plotted your course or the NATs close to your route. All of a sudden you have some sort of emergency that requires you to descend and divert, ie engine failure. . You comply with mandated contingency procedures and now you are diverting. If you haven't plotted your route and know where you are in relation to the NATs of the day, how do you know that you are now not descending right through a NAT with a high volume of traffic? Some food for thought for those who think plotting is not needed.

merlinxx
27th Dec 2012, 13:47
I worked for a FAR91/121 operator overseas, and we never kept planning plotting (NAT's etc) charts. We had our Jepp library, and all our Jepp CFPs were archived per FAA regs.

JammedStab
27th Dec 2012, 13:47
Consider this. You are flying a random route that is over, near, or parallel to one of the days NAT tracks. You haven't plotted your course or the NATs close to your route. All of a sudden you have some sort of emergency that requires you to descend and divert, ie engine failure. . You comply with mandated contingency procedures and now you are diverting. If you haven't plotted your route and know where you are in relation to the NATs of the day, how do you know that you are now not descending right through a NAT with a high volume of traffic? Some food for thought for those who think plotting is not needed.

Thanks G450.....I had not thought of that.

So then when you plot your random route, you also plot the NAT tracks of the day to see where they are in relation to you?

Another quick question that shows my inexperience....do you do a contingency procedure from a random route?

g450cpt
27th Dec 2012, 13:57
If my random route has me anywhere near the NATs or my diversion alternate has me flying through the NATs to get me from my random route to my alternate, then yes, I plot the NATs also. That way if I have a problem while on a random route I can apply the driftdown contingency and fly parallel to the NAT until I get below then proceed to my alternate. That is much safer for all involved than having someone driftdown perpendicular through the NATs.

Spooky 2
27th Dec 2012, 14:04
I think fdr is missing the point but I doubt that anything will chnage his mind at this late date. There are so many examples of the PP saving one's arse that there is not room here for that discussion. I have to wonder who he was flying for in those days?:}

BTW, I have yet to see an approved polar plotting chart?:confused:

misd-agin
27th Dec 2012, 14:43
Company Ops Specs - If it's printed on a chart no plotting required. That means tracks and random require plotting.

jaja
27th Dec 2012, 14:51
OK I only do the "inter european" routes.

Occasionally when flying from northern Europe to the Canaries, we use T9 and T16. Here we do not use plotting, even though there is more than 725 nm between navaids (ref extract from AC91-70A below)

Is that wrong ??



3-6.
POSITION PLOTTING.
a.
Plotting and Systematic Cross-Checking of Navigation Information. During all phases of flight in Class II navigation, each operator’s long-range navigation program (LRNP) will require the standardized application of disciplined, systematic cross-checking of navigation information.
(1)
Plotting Procedures Impact. Plotting procedures have had a significant impact on the reduction of gross navigation errors (GNE). There is a requirement to plot the route of flight on a plotting chart and to plot the computer position approximately 10 minutes after waypoint passage. This may or may not require plotting, depending upon the distance between the standard ICAO ground-based NAVAIDs. This applies to all operators.
(2)
Turbojet Operations. All turbojet operations, where the route segment between the operational service volume of ICAO standard ground-based NAVAIDs exceeds 725 NM, require plotting procedures.

flyburg
27th Dec 2012, 14:52
G450cpt,

Sorry, but highly unlikely! Even a random route will be more than 60 NM from the NAT tracks. You say you have some sort of emergency and you comply with the contingency procedures! Those will ensure you don't cross a NAT track!! For example an emergency descent. Then, if you have to divert and unable to obtain a reclearance there are further contingency procedures on how to proceed in that case. No amount of plotting will keep you safe if you don't adhere to those procedures!

In the unlikely event that you have an emergency descent, an engine failure, an FMS failure and a radio failure and have to divert, I think common sense should prevail, I'd think you'd be a little to preoccupied to come up with an exact course from your plotting chart and besides that after an emergency descent you'd be below the NAT tracks!!

In my company, GNE is (tempted to) avoided by strict adherence to cross checking procedures, both pilots write down the clearance, one inserts the route, both pilots check that and the tracks and distances, in case of unplanned route consult the track versus distance table etc, etc, before or in case of reclearance while on the tracks or random.

I guess I really don't see the advantage of the plotting chart if you have checked with both pilots the route, the tracks and distances etc, etc! I see the magenta line, I see the aircraft symbol but I have to check the POS page and compare that to a plotting chart?? I'd say that if the airplane symbol is not on position as indicated on the pos chart the FMS is corrupted anyways!!

Now, for situational purposes, in case the FMS dies, I have the enroute chart out, I have the cool little pointy stickers that you can buy at office max and put them on the chart at my coordinates, so I know approximately where I am. If my FMS dies, I'm going to follow the headings on my flightplan, if I have to divert I doubt whether the plotting chart is going to give me anymore accurate calculations than some mental arithmatic, unless that emergency occurred right at the time I updated my plotting chart.

In closing, plotting charts where great in the past, however, today, with the extreme and redundant navigation systems onboard, I really don't see the advantage!

Edited, okay, if you happen to be on a random route OVER the NAT tracks it may have an advantage, but however I think TCAS and the probable chance that you'd hit somebody on the way down?? How would you compare that than emergency descent over busy Europe or northern America? Seriously? I would just follow NAT procedures, go down an monitor or follow TCAS and look outside!! And not inside at my plotting chart!!

galaxy flyer
27th Dec 2012, 15:32
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.

flyburg
27th Dec 2012, 15:44
OK, Never too old to learn!

Al crossing have either been on the tracks, north or south of them. Never across and never above since we are generally to heavy to get above them.

I'll have to read up on those procedures you describe I guess, I can't recall those. If that's true, I stand corrected!

galaxy flyer
27th Dec 2012, 16:08
I've done crossings at 430 where we crossed EVERY track, so it would have been near impossible to correctly align with one of the tracks accurately. That's why I went to just flight planning along the nearest track, whenever possible. I do load the nearest tracks in the FMS, just to be ready.

I will say, the diverts I have done, door issues and an engine failure were a non-event. In all cases, Gander or Shanwick handled it with ease once they worked out our position and request.

g450cpt
27th Dec 2012, 16:13
Yes our random routes overfly the NATs all the time. We better know where we are in relation to the NATs so if we have a problem we can align with the NAT and driftdown 15 nm offset. Yes we may be busy at that point but having our route plotted and having the NATs already plotted makes life a lot less busy. As for TCAS taking care of all collision avoidance, if you could ask the crew and pax of the Gol 73 that collided with EMB jet over South America. They both had TCAS.

Spooky 2
27th Dec 2012, 16:38
Another example where the plotting chart is mandatory would be going from Seattle to Tahiti. You cross all the ATS routes during this leg and doing so without plotting your track plus all the tracks you cross during this leg should be mandatory and anything less is almost criminal. Sort of like crossing a major highway without looking. I for one would like to see the OpsSpecs of those operators that are operating in an oceanic environment that do not require plotting. I know enough FAA International Ops Inspectors that I doubt that they would ever sign off on a deletion of this practice.

flyburg
27th Dec 2012, 17:18
Ok, ok, gave me something too think about!!

For practical purposes, do you plot all NAT tracks into the plot? That seems like quiet a workout? When you take it that seriously, you are not just going to plot one track and than draw parallel lines do you?

g450cpt
27th Dec 2012, 17:42
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.

flyburg
27th Dec 2012, 19:07
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 :ok:

misd-agin
27th Dec 2012, 19:53
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.

flyburg
27th Dec 2012, 20:30
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!

g450cpt
27th Dec 2012, 21:11
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.

JammedStab
27th Dec 2012, 22:59
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.

galaxy flyer
27th Dec 2012, 23:45
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!

mutt
29th Dec 2012, 15:38
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.

rsiano
30th Dec 2012, 17:57
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....

galaxy flyer
30th Dec 2012, 19:16
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.

JammedStab
3rd Jan 2013, 16:49
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.

LeadSled
4th Jan 2013, 01:59
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.

JammedStab
8th Jan 2013, 02:15
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.

galaxy flyer
8th Jan 2013, 02:25
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!

fdr
8th Jan 2013, 04:23
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).

LeadSled
8th Jan 2013, 06:54
(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.

JammedStab
8th Jan 2013, 09:33
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.