The KD2G was a mid-wing, twin-tailed aircraft of similar design to the KDG Snipe which Globe was already supplying to the Navy.

[1] The fuselage was constructed of steel tubing with a duralumin monocoque covering; dural was also used for the flying surfaces.

[2] Recovery, if it survived its mission, was by a 32-foot (9.8 m) diameter parachute; the Firefly was designed to be able to float for up to 15 minutes in the event of a water landing.

The improved KD2G-2, powered by a Solar PJ32 pulsejet, began production in 1950;[1] it was the first successful jet-powered target drone to be developed following the end of World War II.

[1] A KD2G-2 is displayed at the Aircraft Pavilion of the Battleship Memorial Park in Mobile, Alabama.