Interest in the auto-gyro by the USN resulted in the purchase of two Pitcairn PCA-2 autogyros, modified as two-seat observation platforms, designated XOP-1.

Trials with the XOP-1s from 1931 had limited success, but included an operational deployment in Nicaragua from June 1932, with the United States Marine Corps (USMC).

The tail unit consisted of a very wide chord fin and rudder with a strut supported tail-plane sporting up-turned wing-tips.

[1] Power was supplied by a nose-mounted 420 hp (310 kW) Wright R-975E-2 in a tight-fitting wide chord cowling with blisters to accommodate rocker arms.

On 30 March 1936, whilst on test, NACA 88 suffered a rotor failure, prompting the crew to perform the first successful bail-out from a rotary-winged aircraft.