From 1977 to 1981, I lived near 109 Street just South of the High Level Bridge, along the flight path into The Muni, the Edmonton Municipal Airport. Pacific Western Airlines (PWA) made every effort to have their first Airbus flights of the day leave Calgary and Edmonton at exactly 7:00 AM, to get passengers into Downtown Edmonton and Calgary offices at the beginning of the Business Day.
By this point in their history, PWA had moved to nothing but Boeing 737 jet aircraft. And, as coincidences would have it, a 737 leaving Calgary at 7:00 AM flew over my home at 7:37 AM, flying low and loud, on its final approach into the Muni.
During the latter years of that period, after my employer adopted Flex Time and I was finally free of the 8:00 AM start of the workday favoured by Engineers, I used that 737 as my alarm clock. Something I would have never expected just a few short years earlier, when I lived in Yellowknife, where PWA stood for Please Wait Awhile.