Turnpoint list creation checklist

I am in the process of creating / editing a turnpoint list for another site in the US. I have created a few, this time I thought it might be good to gather input on what the best practices to do this as efficiently and accurately as is reasonable. Here the the notes I've written up so far on a check list. I would like to hear any helpful feedback.

* Establish a boundary based on possible best flights on best day ever, and remove all airstrips/airports "well outside" the boundary (items close to the boundary will probably be included for completeness).

* Remove all obviously abandoned/missing airports/airstrips.
Add in airports within the established boundary that are in the nearby databases, but not in the current database.

* Decide which are Turnpoints for contest and badges and what are additional landpoints, Plan points for 300+500km O&R & Triangles, plan to Accommodate the Best Pilot on the Strongest Day.

* Check to see if any TP are listed at 0ft MSL by error.

* Check each point in Google Earth, often the location is very wrong in official databases, do not change FAA data if its not off by more than about 750' in distance or 50'altitude. [bias toward offical data].

* Review special use airpace in task area.

* Separate turnpoints for Start and Finish?

* Verify Attributes, HSFTA, G

* Verify spelling

* Convert Metric Alt to feet if needed [or inverse]

* Renumber

* Sort all points alphabetically and see if any truncated names would be identical, such as a Turnpoint name Etowah, and a landable point called Etowah Bend.

* Names should not include special characters which are incompatible with 1 or more gps systems, examples: , ' * ! : ; & $

* Turnpoint names which start with numbers can be bad: number 2 which was 411X64 in the current database is a bad name for some software since it shows up as 02411X64 and computers think it is turnpoint number 2411 and put it at the bottom of lists.

* Names need to work (be differentiated) when truncated down to 6 and 8 characters, some navigation systems only display 6 characters, also some TP file formats have 2 numbers at the front of the name so that takes away 2 letters. Some systems such as SeeYou will abbreviate by eliminating vowels, this can make some names worthless and will need to be edited to have critical vowels.

* Regarding coordinate correction, Generally, John L's process "snaps" coordinates within a given radius of official airport coordinates to the airport coordinates. Of course this is not always appropriate (coordinates wrong etc). So give him a list of stuff not to snap and he will code it to be left alone."

* Recheck names and positions after getting back from Leibacher.

* Test import into scoring program, Winscore or SeeYou, and cockpit nav programs if possible.

* Review with other stakeholders.

* Approve for release.


---

On a side note the more I discuss with people which landout spots should be included the more I want to add more points. I hear comments like that "field could have a crop in it", or it might not be usable due to such and such. The same can be said of airports, I've see airports be closed due to accidents or maintenance, or to be converted into farm fields or housing developments. Perry last year had something like 2 gliders blocking 2 parts of the runway at the same time - a gear up and something else, pretty much made it hard to use for the people low in the pattern.

As far as I can tell there is no way to guarantee that ANY field, paved or grass runway will be available or useable when you want it. All points in a turnpoint file should be considered with suspicion until you get to inspect it from the landing pattern.


Chris

A good start!

Most important though: Keep a CAREFUL record of all your changes,
as you'll need to repeat the process next time the official source
is updated. Make this info available to reviewers as well.

Hope this helps,
Best Regards, Dave

PS: Are you going to tackle local airspace info customization too?

On Wednesday, November 19, 2014 6:34:09 PM UTC-8, Dave Nadler wrote:
A good start!

Most important though: Keep a CAREFUL record of all your changes,
as you'll need to repeat the process next time the official source
is updated. Make this info available to reviewers as well.

Hope this helps,
Best Regards, Dave

PS: Are you going to tackle local airspace info customization too?

Looks like a thorough approach to me.
Local airspace can be retrieved using Lynn Alley's excellent website.
FAA data can be added there too, but if you have information you would like to keep from your own database proceed it with a tilde (squiggly thing).
Jim

Consider how turnpoints for a long MAT could be arranged. Some CD's like the idea of spiralling a long MAT in towards the finish point, such that the incremental distance of each successive point results in the addition of about 10-15 minutes on task.

A very good process! I would only object to the notion of "bias"
towards the official data.
Wrong is wrong, no matter who publishes the information. If you know
that the official data is incorrect, publish the correct data for glider
use and notify the publisher of his mistake. Maybe he'll even correct it.

Dan Marotta

On 11/19/2014 7:15 PM, wrote:
I am in the process of creating / editing a turnpoint list for another site in the US. I have created a few, this time I thought it might be good to gather input on what the best practices to do this as efficiently and accurately as is reasonable. Here the the notes I've written up so far on a check list. I would like to hear any helpful feedback.

* Establish a boundary based on possible best flights on best day ever, and remove all airstrips/airports "well outside" the boundary (items close to the boundary will probably be included for completeness).

* Remove all obviously abandoned/missing airports/airstrips.
Add in airports within the established boundary that are in the nearby databases, but not in the current database.

* Decide which are Turnpoints for contest and badges and what are additional landpoints, Plan points for 300+500km O&R & Triangles, plan to Accommodate the Best Pilot on the Strongest Day.

* Check to see if any TP are listed at 0ft MSL by error.

* Check each point in Google Earth, often the location is very wrong in official databases, do not change FAA data if its not off by more than about 750' in distance or 50'altitude. [bias toward offical data].

* Review special use airpace in task area.

* Separate turnpoints for Start and Finish?

* Verify Attributes, HSFTA, G

* Verify spelling

* Convert Metric Alt to feet if needed [or inverse]

* Renumber

* Sort all points alphabetically and see if any truncated names would be identical, such as a Turnpoint name Etowah, and a landable point called Etowah Bend.

* Names should not include special characters which are incompatible with 1 or more gps systems, examples: , ' * ! : ; & $

* Turnpoint names which start with numbers can be bad: number 2 which was 411X64 in the current database is a bad name for some software since it shows up as 02411X64 and computers think it is turnpoint number 2411 and put it at the bottom of lists.

* Names need to work (be differentiated) when truncated down to 6 and 8 characters, some navigation systems only display 6 characters, also some TP file formats have 2 numbers at the front of the name so that takes away 2 letters. Some systems such as SeeYou will abbreviate by eliminating vowels, this can make some names worthless and will need to be edited to have critical vowels.

* Regarding coordinate correction, Generally, John L's process "snaps" coordinates within a given radius of official airport coordinates to the airport coordinates. Of course this is not always appropriate (coordinates wrong etc). So give him a list of stuff not to snap and he will code it to be left alone."

* Recheck names and positions after getting back from Leibacher.

* Test import into scoring program, Winscore or SeeYou, and cockpit nav programs if possible.

* Review with other stakeholders.

* Approve for release.


---

On a side note the more I discuss with people which landout spots should be included the more I want to add more points. I hear comments like that "field could have a crop in it", or it might not be usable due to such and such. The same can be said of airports, I've see airports be closed due to accidents or maintenance, or to be converted into farm fields or housing developments. Perry last year had something like 2 gliders blocking 2 parts of the runway at the same time - a gear up and something else, pretty much made it hard to use for the people low in the pattern.

As far as I can tell there is no way to guarantee that ANY field, paved or grass runway will be available or useable when you want it. All points in a turnpoint file should be considered with suspicion until you get to inspect it from the landing pattern.


Chris

On Wed, 19 Nov 2014 18:15:09 -0800, greeneggsandjam wrote:

* Names need to work (be differentiated) when truncated down to 6 and 8
characters, some navigation systems only display 6 characters, also some
TP file formats have 2 numbers at the front of the name so that takes
away 2 letters. Some systems such as SeeYou will abbreviate by
eliminating vowels, this can make some names worthless and will need to
be edited to have critical vowels.

I don't know if this will help you with shortening long turnpoint names,
but here is a description of how I generate 12 character names for use
with Cambridge/Winpilot and Zander equipment or 16 character names for
FLARM. It seems to generate fairly readable shortened names and was
straight forward enough to include in a program.

In the UK the British Gliding Association maintains a list of over 1200
turnpoints covering the whole country. It assigns a unique three
character capitalised ID, known as a trigraph, to each turnpoint. The
following describes how to work the trigraph into before shortening the
name so its usable with the target navigation kit. If you don't want or
need trigraphs, simply skip step 1. The aim of the following is to
produce a unique, readable short version of the turnpoint name with the
trigraph, if there is one, forming the first three letters of the
turnpoint name.

1 If the trigraph is the same as the first three characters of the
waypoint name, use the name, truncated as necessary, with the
first three characters capitalised. If they differ the trigraph,
followed by a space, is added in front of the waypoint name.

My waypoint database includes both BGA turnpoints, which have trigraphs,
and non-gliding airfields or other landout points, which don't have
trigraphs. This is why the trigraph is treated as optional.

If the resulting name exceeds the required length it is compressed
by applying the following steps in the order shown. Stop as soon as
a step has made the name short enough for the target device.

2 Remove spaces apart from the one that follows the trigraph.

3 Remove all characters that aren't alphanumeric or spaces.

4 Remove lower case vowels from the right, stopping if the target
length is reached.

5 If the name is still too long, truncate it by removing the
excess characters from the right hand end.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

(This reply is specific to the USA)

Chris,

Your list shows that you have put a lot of good thought into the topic. However, I've been creating turnpoint lists for contests and other uses for some years, and my process looks quite different. There are a couple of reasons for this:

- There are automated tools to do many of the things you mention, such as generating names, renumbering, composing airport lists, and so forth.

- The problem of keeping the airport data current is actually much more difficult than you might think. Most of the tunrpoint lists I see are materially stale. This happens because airports (especially private ones) close, frequencies and ID's change, and so forth. These kinds of changes are actually more frequent than many people realize.

So here is my process:

1. Concentrate on getting the control points established first, primarily using tasking considerations. These are the ones that would be numbered points in a contest, including the starts and finishes. Produce a list that contains ONLY the control points. Many people like to use SeeYou for this planning, and produce a .CUP file at the end.

2. Add to this list any unofficial airports or outlanding places you might want to include. These are the ones that would not appear in official databases. Designate these as "Outlanding Place" in SeeYou. This plus the control points from step #1 become your master list.

3. Compose a "black list" of airports that you want to exclude from your final database. These are ones that appear in the official sources, but for some reason should not be included. Perhaps the airport doesn't actually exist, or there is some reason you really wouldn't want to land there.

4. Use an automated tool such as my website (http://www.soaringdata.info) to fill the turnpoint list with airports. There are a couple of ways of doing this. One is to select a centerpoint and a radius. Another is to let the system to compute a bounding polygon for the turnpoints, and include all the airports within or near the boundaries. My system will produce a Soaring Turnpoint Exchange (STX) format file as well as CUP and a few other output formats. It will also automatically produce companion special use airspace files for the area covered by the turnpoints.

5. Make any hand edits you think necessary. You can choose to correct mistakes that might originate in official data here. There is also a way to make error reports to the FAA so that the official data gets fixed.

6. Submit the STX file to the Soaring Turnpoint Exchange. John Liebacher has automated tools to automatically translate it to literally dozens of different formats, complying with name and other restrictions unique to each..

7. When it comes time to update the database, you just start at step #4. You get fresh airport and airspace data painlessly.

I can provide detailed help with any of these steps if you would like to contact me separately. You can use the "Questions and Comments" link on my site.

Best of Luck

Lynn Alley
"2KA"

On Wednesday, November 19, 2014 9:15:10 PM UTC-5, wrote:
I am in the process of creating / editing a turnpoint list for another site in the US. I have created a few, this time I thought it might be good to gather input on what the best practices to do this as efficiently and accurately as is reasonable. Here the the notes I've written up so far on a check list. I would like to hear any helpful feedback.

* Establish a boundary based on possible best flights on best day ever, and remove all airstrips/airports "well outside" the boundary (items close to the boundary will probably be included for completeness).

* Remove all obviously abandoned/missing airports/airstrips.
Add in airports within the established boundary that are in the nearby databases, but not in the current database.

* Decide which are Turnpoints for contest and badges and what are additional landpoints, Plan points for 300+500km O&R & Triangles, plan to Accommodate the Best Pilot on the Strongest Day.

* Check to see if any TP are listed at 0ft MSL by error.

* Check each point in Google Earth, often the location is very wrong in official databases, do not change FAA data if its not off by more than about 750' in distance or 50'altitude. [bias toward offical data].

* Review special use airpace in task area.

* Separate turnpoints for Start and Finish?

* Verify Attributes, HSFTA, G

* Verify spelling

* Convert Metric Alt to feet if needed [or inverse]

* Renumber

* Sort all points alphabetically and see if any truncated names would be identical, such as a Turnpoint name Etowah, and a landable point called Etowah Bend.

* Names should not include special characters which are incompatible with 1 or more gps systems, examples: , ' * ! : ; & $

* Turnpoint names which start with numbers can be bad: number 2 which was 411X64 in the current database is a bad name for some software since it shows up as 02411X64 and computers think it is turnpoint number 2411 and put it at the bottom of lists.

* Names need to work (be differentiated) when truncated down to 6 and 8 characters, some navigation systems only display 6 characters, also some TP file formats have 2 numbers at the front of the name so that takes away 2 letters. Some systems such as SeeYou will abbreviate by eliminating vowels, this can make some names worthless and will need to be edited to have critical vowels.

* Regarding coordinate correction, Generally, John L's process "snaps" coordinates within a given radius of official airport coordinates to the airport coordinates. Of course this is not always appropriate (coordinates wrong etc). So give him a list of stuff not to snap and he will code it to be left alone."

* Recheck names and positions after getting back from Leibacher.

* Test import into scoring program, Winscore or SeeYou, and cockpit nav programs if possible.

* Review with other stakeholders.

* Approve for release.


---

On a side note the more I discuss with people which landout spots should be included the more I want to add more points. I hear comments like that "field could have a crop in it", or it might not be usable due to such and such. The same can be said of airports, I've see airports be closed due to accidents or maintenance, or to be converted into farm fields or housing developments. Perry last year had something like 2 gliders blocking 2 parts of the runway at the same time - a gear up and something else, pretty much made it hard to use for the people low in the pattern.

As far as I can tell there is no way to guarantee that ANY field, paved or grass runway will be available or useable when you want it. All points in a turnpoint file should be considered with suspicion until you get to inspect it from the landing pattern.


Chris

Also of interest (at least in our club's lists) have been the other glider
clubs in the region, out to a fair distance. We like hunting the BRSS Boomerang
Trophy, so it's nice to have its various homes at hand.

On Thu, 20 Nov 2014 21:09:46 +0000, Tim Newport-Peace wrote:

IGC did publish a Waypoint File Format:
http://www.fai.org/component/phocadownload/category/?
download=3557:wpform
at

Yes, Tim, I have a copy of that, thanks.

I note that the BGA trigraphs seem to be compliant with it. However, I
don't think I've seen a device-specific TP file that is 100% compliant
with it. Are there any?

I also had a link to a discussion document about the IGC Waypoint File
format. The discussion took place around around 2005 and the document
used to be accessible at:

http://www.aviationkb.com/Uwe/Forum....erd-Challenge-
Google-TP-map

but it seems to have vanished. The aviationkb.com domain is for sale and
is now just a holding page. The Wayback Machine doesn't have a copy of
the document either, so does anybody know the whereabouts of an
accessible version of it?

I got the TP name shortening algorithm from Jeff Goodenough. It generates
matches for the TP names and descriptions in CAI/Winpilot format files
output by TPSelect if the input is the original TP name and trigraph from
your master list.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On Thursday, November 20, 2014 9:23:42 AM UTC-5, Dave Springford wrote:
Consider how turnpoints for a long MAT could be arranged. Some CD's like the idea of spiralling a long MAT in towards the finish point, such that the incremental distance of each successive point results in the addition of about 10-15 minutes on task.

Dave,
Good point, I usually add several short distance Turnpoints and steering points near finish, but forgot to add that to my checklist. These have been useful at Cordele and elsewhere.
regards,
Chris