Jonathan Edward Caldwell - Autogyro

Autogyro

In 1934 Caldwell moved again, this time to Washington, DC. In a filing with the Maryland Securities and Exchange Commission he described the company as working solely on a new type of autogyro, which he referred to as a "disk-rotor plane".

The design consisted of a fairly conventional autogyro layout, but the wing was disk-like instead of the more traditional helicopter-like bladed assembly. The disk had airfoils formed out of fabric on the inside of the rim, and four small solid surfaces on the outside. In forward motion the airstream blowing across the four small surfaces would spin the disk, which would provide lift from the fabric airfoils inside. On reaching cruising altitude, the disk would be braked to stop it spinning, and unbraked again for a near-vertical landing. The advantage to this arrangement was that there was no theoretical limit on forward speed, whereas a conventional autogyro cannot be stopped in flight, and has a limit when the speed of the rearward moving blade approaches the stall speed.

Unlike his previous attempts, the disk-rotor aircraft was actually completed between 1936 and 1938, and was issued a CAA experimental registration number NX99Y. In late 1937 or early 1938 a test flight was attempted with the company mechanic at the controls, Willard Driggers. According to later claims (see below), Driggers managed to get the aircraft airborne from the Benning Race Track, and in a panic cut power, causing the aircraft to crash-land, damaging the landing gear. Although damage was minor, Caldwell had apparently already lost interest in the design and did not repair it.