It is clear that the current OpenAir specification as published online at http://www.winpilot.com/usersguide/userairspace.asp has flaws in it. I propose the following actions to improve this:

1. Document the defects, inconsistencies and design flaws of the current OpenAir specification online at http://www.winpilot.com/usersguide/userairspace.asp in a text file.
2. Contact WinPilot, who is for as far as I know the company officially in charge of the OpenAir specification, and ask them if there is already a newer version of the OpenAir standard.
3. Contact the people from XCSoar to see if they have ideas for a better OpenAir standard.

A lot of airspace files have TMZ as their airspace class:

bart@kulak:~/oaconvert/openair$ grep -rlI "AC.*TMZ" *
countries/netherlands/tmz_g1.txt
countries/netherlands/tmz_d_part1_1.txt
countries/netherlands/tmz_eelde_1.txt
countries/netherlands/tmz_d_malden_2.txt
countries/netherlands/rotterdam_tmz_1.txt
countries/netherlands/maastricht_tmz_1.txt
countries/netherlands/tmz_e_2.txt
countries/netherlands/tmz_a_1.txt
countries/netherlands/maastricht_tmz_2.txt
countries/netherlands/tmz_b_2.txt
countries/netherlands/tmz_d_part2_1.txt
countries/netherlands/tmz_eelde_2.txt
countries/netherlands/tmz_d_part1_2.txt
countries/netherlands/tmz_a_2.txt
countries/netherlands/tmz_b_1.txt
countries/netherlands/tmz_e_1.txt
countries/netherlands/rotterdam_tmz_2.txt
countries/netherlands/tmz_c_1.txt
countries/netherlands/tmz_d_part2_2.txt
countries/netherlands/tmz_c_2.txt
countries/germany/dortmund_gpb.txt
countries/germany/dortmund_gpd.txt
countries/germany/dortmund_gpa.txt
countries/germany/dortmund_gpc.txt

Since TMZ is not an official airspace class as defined by http://www.winpilot.com/usersguide/userairspace.asp we should remove TMZ from the AC-record and decide what airspace class it belongs to. Furthermore, the AN-record should have TMZ as part of the string. There are two options:

1. Write TMZ at the beginning of the AN-record, something like

AN TMZ Rotterdam

2. Write TMZ at the end of the AN-record, something like

AN Rotterdam TMZ

My personal preference is 1 because for long strings that do not entirely fit on the screen, TMZ will still be visible, which is more important than the name of the airspace class.

Create a text file that lists the different OpenAir dialects.

• WinPilot: http://www.winpilot.com/usersguide/userairspace.asp
• XCSoar: see for example http://git.xcsoar.org/cgit/master/xcsoar.git/tree/src/Airspace/AirspaceParser.cpp
• ... other...?