LOGIN to post messages, upload log files
and access membership list
Discussion Forum
All posts subject to Decency Guidelines !

Forums | ┬Ąt_page=1 | Subject:Solution to Grand Canyon airspace problem Log on to post a reply !
Author Thread
Cliff HiltyReply: posted - 19 June 2017 7:32
Unfortunately not! My Garmin is as I said showing top of the GC airspace up to 18k and not showing any of the corridors or for that matter any of the frequencys. I asked Garmin a few years ago to include the airspace but without any luck. I use a paper chart if I am flying the 170 thru and am pretty sure foreflight has all of it in there.
jsilvasiReply: posted - 18 June 2017 16:52
FAR 93.301 thru 93.325 and their associated appendices delineate the geospatial and operational characteristics of and pilot requirements for operations within the Grand Canyon Special Flight Rules Area. Changes to the geometry of the SFAR would require congressional input and NPRM process, so it's unlikely that we'll see any changes to the airspace definitions. (The last changes occurred in April 2000.) But frequency and other non-airspace changes occur much more frequently. When added to the Arizona special use airspace file, it was defined as a single area extending from the surface to 14,500'. If you treat it as such, you will be completely legal, but short changing yourself greatly as there is a significant amount of airspace that you can fly thru legally below 14,500' !! I'm guessing that your Garmin shows the correct sector altitudes and boundaries as well as the flight free zones and VFR corridors. Unfortunately, these comprise quite a complex group of SUA definitions, more complex than the PHX Class-B airspace definitions. At least those can be described with point to point line segments and point-radius-arc definitions. There are several depictions required for the GCSFAR that cannot be defined in Tim Newport-Peace or OpenAir formats*. Therein lies the conundrum - how to provide a more accurate depiction as a compromise.

* For example, the VFR corridors are defined as 2 miles either side of a line from GPS point A to GPS point B and significant portions of the Flight Free Zones are described as being "along the park boundary". Sector boundaries represent another difficulty. This Airspace was complex enough for the FAA to create a special chart just for it: https://www.faa.gov/air_traffic/flight_info/aeronav/productcatalog/vfrcharts/GrandCanyon/.

Joe Silvasi

Steve KoernerReply: posted - 18 June 2017 6:03
Based on this document, I'd conclude there has not been any significant changes in GC airspace as of April 27, 2017:


Cliff HiltyReply: posted - 17 June 2017 21:42
I don't understand most or anything of what you are talking about but my last flight up there was two weeks ago and my 6 month ago updated Garmin 196 file now shows the grand canyon airspace as all the way to 18k instead of 14.5 as it was previously. Not sure if it is actually that or not but. Interesting
jsilvasiReply: posted - 13 June 2017 19:16
It was meant to be, but there is some technical difficulty with it being directly downloadable to the ClearNav devices. In the next generation of the spreadsheet, I have removed the tabbed nav files and will instead be generating the files programmatically. I will have much more control of the generated file content to insure that they work properly. I've got a couple minor bugs in the SUA files that I've got to identify and iron out as well as the GCSFAR. At least I think I have a plan for the flight free and corridors that I'm going to try: it will be something like the way Class-B airspace is currently handled. Since there have been so many changes to airport turn points, I'm trying to get a process that will permit more frequent download and update of turn point data. With the latest airport changes, there are 476 turnpoints bounded by N31.000 - N38.000 and W107.500 - 115.500 which covers all of AZ and portions or CA, NV, UT, CO and NM.

Joe Silvasi

Steve KoernerReply: posted - 12 June 2017 11:32
Joe: Glad to see that you're working on this.

Your spreadsheet includes an STX tab. Do you have a process for creation of a .stx file? Is it tested?

jsilvasiReply: posted - 12 June 2017 8:30
An Update - I have been making a number of upgrades to airspace, turn points and obstacle data for the AZ turn point database recently. I have developed a process which extracts all SUA elements within a bounded area from a single nationally updated source and produces both Tim Newport-Peace and Open Air format SUA files; OpenAIP format for iGlide computers is still in the works. I have developed another procedure which identifies and extracts airport, gliderport and ultralight strip information directly from the FAA National Flight Data Center files that have replaced what we used to call the Airport Facilities Directory that is now no longer produced. (We now have “Chart Supplements” which sadly does not contain all of the airport information that the old AFD used to, so this data now must be compiled from 5 different sources.) Two areas remain elusive. First, man made obstacle data (used for charting which is of interest to glider pilots as many of these tend to serve as waypoints for our activities) - the sheer number is mind boggling and natural obstacle data which has not yet been identified despite numerous attempts. Second, the Grand Canyon Special Flight Rules Area. The big issue here is that there is no SUA encoding which provides open ended charting of airspace that the display layer can depict on your flight computers - current coding and flight computers assume closed loop encodings (i.e. A to B to C and back to A) but make no provision for open ended corridors as needed for the GCSFAR. I’m working on a compromise for that but do not have a firm solution in place at this time.

I April I gave a presentation to the Arizona Soaring Interest Group (ASIG) about the state of turn point development in Arizona. That presentation can reviewed at


and the companion Arizona Turnpoint Master List (ATML) that I mentioned at


However, I’ve now moved into version 7 of the spreadsheet by streamlining the distance calculations, merging/updating airport information from data gathered from the NFDC. Many airports that we had in the database are now no longer airports plus there are new airport designations, some frequencies have changed and remarks have been updated. As always, your constructive comments and suggestions are always welcomed as part of the process, that’s why there is a turn points discussion in the Forum.

Joe Silvasi

Steve KoernerStart of thread: posted - 10 June 2017 14:36
Avare is an outstanding moving map airplane app for android. Avare is a non-profit project financed through donations and is free to download and install on your device. For the last couple years I've been carrying a tablet in order to have Avare available in the glider. Now, I've found that my new phone is brighter and somewhat easier to see so I've setup a phone holder on my panel. That facilitates running IGCdroid as well as Avare and in-flight text messaging too. I added a 5 volt USB jack on the panel so that the phone can be kept charged from the glider's battery.

Anyway, the main point of this post is that the Grand Canyon detail chart can now be loaded into Avare. With that you can see and navigate the 14,500 foot "flight free zones" as well as the 8000 ft, 9000 ft and 10000 ft sector areas and the several corridors through the flight free zones. The GC chart is a little tricky to find in Avare - it's filed under "Heli/Other" in the download area. I imagine there might be other programs now that have the GC chart available besides Avare.

Knowing the details of the Grand Canyon airspace has been a big problem ever since Ted Wagner cleverly introduced the Grand Canyon airspace into the soaring community databases but left a blanket 14,500 ft ceiling on the whole area. That effectively made it almost impossible to fly the Canyon.

The real irony is that the stated purpose of the airspace there is to ensure "natural quiet". Gliders, of course, are inherently so; yet the government makes no allowance for us. Several years ago I made a lengthy and impassioned plea to an appropriate government committee on that particular point and sadly never even receive the courtesy of a reply from them. It's truly an injustice that we have to deal with this at all.

Log on to post a reply !