03/31/2022. Remarks by Johan Visschedijk: "Piper built two prototypes of the PA-31.

PA-31 Inca (N3100E) (Johan Visschedijk Collection)

Initially named Inca, the PA-31 was renamed Navajo before the official launch on September 26, 1966. Registered N3100E (c/n 31-1) the first prototype flew on September 30, 1964, the second had its maiden flight more than a year later, December 21, 1965, registered as N3104E (cn 31-2 ). These were followed by two service test aircraft. The first was the pictured aircraft on top of the page, which first flew on June 8, 1966, while the second flew on September 16, 1966, registered as N9000Y (c/n 31-4).

N3105E was lost in an accident on May 3, 1973. More details at Aviation Safety Network."