The Pitcairn Mailwings were developed to carry air mail for the United States Post Office Department. Of simple and robust construction, they had relatively benign flying characteristics.[1]
They were constructed using chrome-moly steel tube and square-section spruce spars with spruce and plywood built-up ribs. The fuselage was faired using wooden formers and covered with fabric. The tail sections were built up from steel tube and fabric-covered. The Pitcairn Mailwing had a ground-adjustable fin and in-flight adjustable tailplane.[1]
The undercarriage was of outrigger type with Oleo-Spring shock absorbers and disc brakes on the mainwheels. All versions looked very similar and changes were minor, with several fuselage extensions being the most obvious.[1]
The mail was carried in a fireproof metal-lined compartment forward of the pilot's cockpit. The Mailwings were flown extensively by the U.S. Air Mail service from 1927 until the end of dedicated Air-Mail routes.[1]
Pitcairn also built the same aircraft in sport versions for private use. These aircraft had the mail compartment removed, and a side-by-side two-seat cockpit was fitted.[1]