The Handley Page O/400 bomber was another airplane of European design that the Americans adopted during WWI. A bomber that was both massive and powerful, given the standards of the time, Lipsner believed it was the perfect plane for delivering mail.
Lipsner first encountered the Handley Page bomber at the August 6th, 1918 JR-1B acceptance ceremony. The Standard Aircraft executives showed Lipsner the bomber and arranged a test flight. At first they had a test plot hired by Standard, afterward Max Miller flew the bomber. According to Lipsner, Miller was favorably impressed by how the bomber handled. He went on to recommend the design to Praeger, who decided that, for the time being, the JR-1Bs were sufficient.
Lipsner rejoiced when, at the conclusion of the war, the army promised the Post Office Department twelve Handley Page bombers. Praeger, however, decided that there was no place in the service for aircraft of such size. Parts from the Handley Pages were used to modify the DH-4s for service. This incensed Lipsner, and he cited it as one of the reasons that he parted company with the Airmail Service.