This cache is located under the approach to runway 17L or departure from runway 35R at YYC. If the planes are arriving from the north then you will get a pretty good view of them as they pass overhead with their gear down. If they are departing to the north then the gear should be up by this point as they climb out. But if you happen to see one climbing out with the gear still down that's ok. Sometimes they leave them down for a little longer to let the brakes cool. Especially on a hot day and if they had a long taxi out to the runway.
No room for anything other than a log, so please BYOP.
Congratulations to "uboff" on the FTF!