ETOPS Plotting software
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Joined: Apr 2008
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From: Playing Golf!
ETOPS Plotting software
Could anyone suggest software for creating ETOPS charts with the various range circles that would overlay that data on an en-route chart?
I am aware of GCMAP.com and I have Jeppesen JeppView but neither are giving the results I desire.
Anything available on the web?
Thanks
PT6A
I am aware of GCMAP.com and I have Jeppesen JeppView but neither are giving the results I desire.
Anything available on the web?
Thanks
PT6A
Joined: Mar 2007
Posts: 1,235
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From: USofA
I believe that is next to impossible on the current Jepp plotting charts for a several technical reasons. I was told this by a Boeing ETOPS specialist and took his word for it without defining the exact reasons. I'll go ask him again and get back to you.
Joined: Mar 2007
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From: USofA
Hope this helps
The basic problem is that the chart projections are inherently non-linear, so an 800 nm circle for example would not be a consistent size across the chart and would actually have a slight egg shape depending on where you were relative to the projection point.
I took a look at some of my pacific examples, and you can definitely see a difference particularly on those which cover a large area. How much difference and how close is close enough? I am not a cartographer so can't really comment on that, however suffice to say there is some degree of inaccuracy when using this approach
I took a look at some of my pacific examples, and you can definitely see a difference particularly on those which cover a large area. How much difference and how close is close enough? I am not a cartographer so can't really comment on that, however suffice to say there is some degree of inaccuracy when using this approach
Joined: Mar 2007
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From: USofA
Here is another response from an expert in this field.
The map projection distorts the picture since it "flattens" the curved earth surface. And an additional "practical" issue is that unless you happen to carry a trammel bar compass with you that is about 2 to 3 ft long, you aren't going to get much of circle anyway, especially when the center of the circle may not even be on the map !!
That said, it isn't always necessary to have really accurate circles. If you are doing a 180-Minute dispatch on the N. Atlantic, it doesn't really matter if you have circles at all. There isn't much of any way that you can plot a track that gets close to the circle boundaries. But there are plenty of conditions where the flight track gets close to the boundary and may even be planned to basically cross the intersection of two circles. This situation is not that uncommon, especially on the N. Atlantic with only a 120-Minute dispatch; 180-Minute dispatches in the southern oceanic areas; and for Polar flights. 240-Minute ETOPS and Beyond will still have the potential for needing to accurately identify the circle intersections, and the length of your trammel bar will go up accordingly.
My advice to airline customers has always been, "Bottomline, pony up and buy the preprinted charts from Jepp, and then you won’t have to keep answering this same question from every pilot in your organization that fancies himself to be "The Navigator".
The map projection distorts the picture since it "flattens" the curved earth surface. And an additional "practical" issue is that unless you happen to carry a trammel bar compass with you that is about 2 to 3 ft long, you aren't going to get much of circle anyway, especially when the center of the circle may not even be on the map !!
That said, it isn't always necessary to have really accurate circles. If you are doing a 180-Minute dispatch on the N. Atlantic, it doesn't really matter if you have circles at all. There isn't much of any way that you can plot a track that gets close to the circle boundaries. But there are plenty of conditions where the flight track gets close to the boundary and may even be planned to basically cross the intersection of two circles. This situation is not that uncommon, especially on the N. Atlantic with only a 120-Minute dispatch; 180-Minute dispatches in the southern oceanic areas; and for Polar flights. 240-Minute ETOPS and Beyond will still have the potential for needing to accurately identify the circle intersections, and the length of your trammel bar will go up accordingly.
My advice to airline customers has always been, "Bottomline, pony up and buy the preprinted charts from Jepp, and then you won’t have to keep answering this same question from every pilot in your organization that fancies himself to be "The Navigator".
Joined: Dec 2009
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From: istanbul
PLOTTİNG CHARTS
Dear Spooky 2
I was looking for to find out is there any regulations such as FAR /JAR /EU-ops which makes mandatory to use plotting charts on ETOPS flights such as North Atlantıc or Transasia Plottıng charts.
Regards
I was looking for to find out is there any regulations such as FAR /JAR /EU-ops which makes mandatory to use plotting charts on ETOPS flights such as North Atlantıc or Transasia Plottıng charts.
Regards
Joined: Mar 2007
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From: USofA
Regulations? Individual operator OpSpecs would probably cover this and in the case of the N. Atlantic, the MNPS manual strongly recommends this. Only a fool would operate on the N. Atlantic tracks without benefit of a plotting chart. Simply to many variables that one might encounter where the plotting chart would bcome the tool of last resort. If your thinking about skipping this little detail please do all of the other operators a favor and let them know when your in the same airspace.
There are exceptions to all the rules and one that comes to mind is west coast of the US to PHNL. There are established fixed tracks beteen these points so you are basically flying an airway which is in your NDB. In this case I have know the FAA to give the operator a pass on plotting but they still need the plotting chart onboard in the event of a reroute. There are also fixed airways in the No Pac but I believe that most if not all operators are still using plotting charts or at a minimum have them available should the need arise. An amended clearance involving a random reroute would be an excellent example.
Not sure what is driving your original question but accepted standards require a degree of compliance with best operating practices. Not plotting, not carrying the correct charts, are but a few of the items that differeniate the pros from the problem children.
Sorry for the harsh words and perhaps I simply read something into your question that did not exist in the first place.
There are exceptions to all the rules and one that comes to mind is west coast of the US to PHNL. There are established fixed tracks beteen these points so you are basically flying an airway which is in your NDB. In this case I have know the FAA to give the operator a pass on plotting but they still need the plotting chart onboard in the event of a reroute. There are also fixed airways in the No Pac but I believe that most if not all operators are still using plotting charts or at a minimum have them available should the need arise. An amended clearance involving a random reroute would be an excellent example.
Not sure what is driving your original question but accepted standards require a degree of compliance with best operating practices. Not plotting, not carrying the correct charts, are but a few of the items that differeniate the pros from the problem children.
Sorry for the harsh words and perhaps I simply read something into your question that did not exist in the first place.
