«Perhaps you could propose a detailed scheme somewhere on the wiki, that we could discuss, and tweak, to come to a consensus? Mind you, it should be universal, not just limited to your own territorium.» This can be done. In what form do you propose to do this? https://wiki.openstreetmap.org/wiki/Proposal_process or in some other? If you are concerned about the general description of ref at wiki and you want to specify the description of this code and you are against the latinized version of this code in "ref" tag, then one of my proposals is to transfer these codes to the another tag: "aftn" or "ref:aftn" (Aeronautical Fixed Telecommunications Network https://en.wikiphedia.org/wiki/aeronautical_fixed_Telecommunication_network because this code is used primarily for this network and for the general identification) and add information about this on wiki https://wiki.openstreetmap.org/wiki/Key:ref + https://wiki.openstreetmap.org/wiki/Tag:aeroway%3Daerodrome. At the moment, I'm observing the only use of "aftn" tag in Croatia near Pula, the use of "ref:aftn" I don't observe. The use of "aftn"/"ref:aftn" tag for latinized version will not be limited to the territories of the former USSR. The use of the AFTN in cyrillic version as "nat_ref" tag value also corresponds to the description on wiki, since this option is used at the national level. I remind you that I am talking exclusively about official identifiers that are appointed state structures of the USSR, the Russian Federation and other states of the former USSR. For amateur identifiers, such as from the site aopa.ru, which aren't included in the official lists and aren't indicated on official airfield schemes, I already proposed using the corresponding tags like ref:aopa:ru & ref:aopa:en (as almost a monopoly source of identifiers amateurs in the Russian Federation). However, if we come to an agreement to use the aftn/ref:aftn tag, then latinized identifiers beginning with U*** but not assigned as an ICAO code should be moved from ref:aopa:en to aftn/ref:aftn, since they are also used in AFTN. It should be noted that the AFTN code, when it contains more than 4 characters, may be used by aerodrome units/departments or aerodrome services