Why do Canadian airport IDs all start with "Y"??

[ogopogo]

(ignoring the "C -". Of course). What's the history on this?

[CID]

Years ago, the weather reporting stations were identified with a two letter identification code. Ottawa had one called "OW" for example. Montreal had one called "UL". Etc....

As airports were being developed, it made sense to locate weather stations on airports. As airports were built, some of the existing weather station locations were adjusted a little to place them on airports. Somebody decided it was a good idea to come up with a method to easily identify which weather stations were co-located with airports so they added a prefix. "N" for "no" and "Y" for "yes".

When the various international standards organizations were allotting airport codes to various countries the Canadian authorities figured that using the new 3 letter weather station code was good start.

In the US, they went another direction and used radio idents for airport codes.

[YVRtoYYZ]

Not all airports in Canada use the CY prefix. Many use 'CZ' (CZBF, CZBM, CZMT, CZNL, etc) while others use an alpha-numerical combination (CAA8, CBS8, CFG6, etc)

[costermonger]

It started (as CID said) as an indicator of a weather station at an airport, but in the last few years a number of smaller airports that never had weather reporting stations have be re-registered with CY codes (like Kincardine - CNS7 to CYKM or Stratford - CNM4 to CYSA, among others) so in at least a few places the answer to this question will simply be 'because airport IDs start with "y"'.

[oldtimer]

I am not so sure it was weather stations that started the trend or the beginning of the RCAF but whoever started the trend started with a 2 letter ID and began with Q, so I suspect Trans Canada Airlines or the RCAF had something to do with it. Anyway, many airports had a 2 letter id, such as, QR for Regina, QF for Red Der, QL for Lethbridge. In the early 60's when I started to fly, the ICAO came more predominant in Canada (and elsewhere) and they required a 3 letter ID so all airports in Canada simply added a Y to make the 3 letter ID. Then, as weather stations grew, some not at an airport got a W desinator. Others had a Z. With the advent of global navigation, there was a requirement for more letters so all of Canada got a C whereas the lower 48 USA got K and Alasks got P.
the 2 letter/one number designator came into being with the development of the CFS.
Now where have I seen this written down, it is just my observations over the last 55 years I have been involved in aviation.

[Meatservo]

An aerodrome near where I live recently changed from an identifier with a number in it to one beginning with a "Y" right when an auto reporting weather station was installed at the field.

[AOW]

Simplest answer: y not?