Upon the assurances of the War Department officials that, with the close of hostilities, the Post Office Department would be enabled to obtain and utilize in the Aerial Mail Service a large quantity of DeHaviland [sic] and other planes, the Post Office Department announced the opening of the New York-Chicago airpost route December the 15th. The DeHaviland planes which the Department expected to obtain were the type known as DeHaviland No. 9, which is said to be a safe and substantial aeronautical work.... The Secretary of War advised that he could not give us the DeHaviland 9’s...but that it would be easy to furnish the Post Office Department with what DeHaviland 4’s would be needed.
The DeHaviland 4 is a weak piece of construction, the fusilage [sic] breaking and the landing gear crumpling in a great percentage of the instances where landings were affected.... In a majority of cases, where landings have been attempted, they have resulted in crumpled landing gears and complete demolition of the planes. It would seem that these planes were designed for front-line work in battle and not built to withstand normal daily landings, on the theory that a plane that makes a forced landing within the enemy’s lines is a lost ship and might as well crack.
Praeger then detailed the dismal record of the DH-4, noting 10 accidents in just 12 days: everything from crumpled, splintered, and faulty landing gear to “ship broken completely in halves and demolished.” A thorough inspection of the aircraft “revealed not only poor material but faulty design.” Anticipating charges of pilot error, Praeger pointed out that five of the 12 aviators “were ‘aces’ in the war in France.... The other aviators were either old experienced exhibition and army flyers or instructors at the Army flying fields.”
Eventually, the Lowe-Willard-Fowler Company of College Point, New York, would come up with several ways to strengthen the DH-4. The fuselage was rebuilt with steel strips; the landing gear fitted with a heavier axle and larger wheels; the pilot’s cockpit moved to the rear compartment; in all, there were close to 20 major changes that finally made the DH-4 a capable mail carrier. The de Havilland 4 would become the workhorse of the Postal Service, with more than 200 serving the organization over a period of eight years.