Originally Posted by
Just a spotter
IIRC, the Aer Lingus/Aerlínte Éireann/Irish International transatlantic routes from the mid 1960’s using the 720’s and 707’s up to the early 1970’s were advertised as “Shamrock Jet Services” and used Shamrock on radio calls.
It’s possible the ‘Shamrock’ callsign spread across the EI network as more jets arrived on the European routes in the 1970’s.
JAS
Sorry, but the latter is not correct. "Shamrock" did not become the standard until many years after Aer Lingus went all-jet on European routes.