Date Line: June 28th,Date1927

The first trans Pacific airplane flight ~ was completed as U.S. Army Corps Lt. Lester J. Maitland and Lt. Albert F. Hegenberger arrived at wheeler Field in Honolulu Hawaii  aboard of the "Bird of Paradise" an Atlantic  Folker C-2 @ 100 mph  over 2,400 miles  from Oakland, CA in 25 hours 50 and minutes.

Date Line June , 1939

Hawahiain Airlines was still known as Inter-Island Airwaves and the fleet consisted of four 'Flying Boats - the Sikorsky 

S-43 Clipper

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Dateline June 28th, 1939 - Pre WW11

Pan American Airwaves began regular Trans Atlantic with a flight that departed New York for Marseilles, France....

June 28th marks the 81st anniversary of the first regular  trans-Atlantic passenger service via  Pan  Am’s Boeing 314 ‘Dixie Clipper’. The aircraft left Port Washington,  New  York with 22 passengers on the southern route to Horta, Lisbon, and  Marseilles. In 1939, the cost of the trip was US$375 for a one-way ticket or US$675 for a round trip.