Coincident with the addition of Saint Joseph, Missouri, Contract Air Mail Route 28 was given twice-daily service. 

The Post Office Department divided the Contract Air Mail Route 28 service into “Day Service” and “Night Service.”

This cover was carried on the October 1, 1929 inaugural Contract Air Mail Route 28 NIGHT FLIGHT flight from Omaha, Nebraska to Saint Joseph, Missouri.

In 1929-1930 Robertson Aircraft Corporation was involved in a series of mergers, ultimately being absorbed by The Aviation Corporation, and operated under the name American Airlines.