You beat me to it NoSig! . I used to fly that route in '72/73 in a BN2 Islander. Loganair operated a twice daily service Monday to Friday between Glasgow and Dundee. Up to Dundee in the morning, back late afternoon, (to GLA) then an evening service from GLA, night stop aircraft/pilot, early morning departure back to GLA. Designed to coincide with the requirements of the business community and provide a feeder to London and Paris services provided by the then BEA.