The Kettering Liberty Eagle ("Bug")
An eager crowd of Army “Brass Hats” were seated in grand stands at the secluded air field near Dayton. They were to witness the flight test of a new weapon, a tiny, pilotless, bi-plane which had the potential to strike the enemy by air without danger to pilots or soldiers. As the miniature craft lifted into the air the development team began to smile and the “hats” began to wonder how this new “missile” could be used in Europe. Just then, the slowly climbing bird pivoted off its course, swooped and dove like a kite flying without enough wind, and headed straight for the reviewing stands. The distinguished crowd, now seemed less so as they dove haphazardly under the bleachers to avoid potential disaster. Fortunately, the craft crash landed a few hundred feet from the invited guests--much to the chagrin and embarrassment of the once-confident development team.
So occurred one of the first ever flights of the “Kettering Flying Bug,” the army’s first guided missile. One of the disheartened developers was Henry H. Arnold, the Deputy Director of the Aviation Division of the Signal Corps. Arnold recalled the test flight seemed to be controlled by the devil himself, the ultimate purpose of his interference unknown.
Col. (Temp) Arnold’s task force of civilian scientists had produced the first "guided missile," dubbed the "Bug," which was a beautiful wood-crafted, mini-biplane. Early versions were simply made of paper maché. It housed a two-stroke, Ford engine and carried a “warhead” of 200-300 pounds of explosives. The “Bug” had no wheels and was launched from a wagon-like contraption which ran on a long section of portable track. The missile’s engine was cranked at one end of the track which was pointed directly at the intended target. When the engine was fully revved, the mechanical counter was engaged and the “Bug” was released. When it reached flying speed, it lifted off and flew straight ahead toward the target, climbing to a preset altitude which was controlled by a supersensitive aneroid barometer. When the “Bug” reached its altitude, the barometer sent signals to small flight controls which were moved by a system of cranks and a bellows (from a player piano) for altitude control. A gyro helped maintain the stability of the craft, the barometer helped maintain altitude, but only the design of the wings assured directional stability. The “Bug” flew straight ahead until a mechanical counter had sensed the calculated number of engine rotations required to carry the weapon the intended target distance. When the preset number of revolutions was reached, a cam fell into place and the wings folded, looking much like a diving falcon swooping down on its prey. The “Bug” was rarely as deadly, and certainly not as fast, as a falcon.USAF Museum, “Kettering Bug” folder. Many photos are included as well as much of the original documents which described the weapon and its construction. Interestingly, Elmer Sperry claimed that he had invented the “Bug” and quit the project in 1919, thoroughly disgusted with Kettering. After the ill-fated test of the "Bug," lateral controls were added which rectified the instability problem caused by over-dependence upon the dihedral--the slightly “upward” angle of the wing in regard to the horizon--for lateral stability.
On the “Bug” team were Orville Wright; Elmer Sperry--who spearheaded the Navy's "aerial torpedo" project a few months earlier; Robert Millikan--soon to be president of Caltech and a future Nobel Prize winner; and Charles “Boss” Kettering--the primary engineer. Most test flights were accomplished at a remote test field in Florida, now Eglin AFB, on the wide open sand dunes which existed in that day. More important than the gadget itself were the members of the team, particularly Millikan, who would play a vital scientific role for the air arm in the 1930s and again during the Second World War. Arnold never forgot his experiences in production, administration, scientific experimentation, or testing. Nor did he forget the men who had helped design and create the missile.
Col. Arnold, realizing the potential importance of the “Bug” to combat operations, convinced the Army Staff to send him to Europe with the device in an effort to persuade Gen. John J. Pershing to use it in the waning days of WW I. Despite several setbacks, Arnold did, finally, make it over to Europe. Officially his orders were to sail by mid-October and become familiar with training organization methods in France and combat operations at the front. Arnold also saw this as an opportunity to see combat action first hand, something he had been denied by his superiors throughout the Great War. His trip was, however, unsuccessful. He immediately fell victim to Spanish Flu which was rampant on the East Coast. After recovery, he made it to the Western Front during November but only a few days before the armistice went into effect. Because the weather was so terrible, however, the “Bug” flew no combat missions and project died shortly thereafter.
But the “Kettering Bug” was not eliminated forever. German treachery in the conduct of the war, particularly with U-boats, jolted Maj Gen Arnold, Commander of the Army Air Forces in WW II, to rekindle the project.
Although using WW I surplus “Bugs” was considered until 1942, the idea was finally dismissed--not because of manufacturing problems, but because of the relatively short maximum range of the weapon (only 200 miles). About fifty of the weapons were in storage and a mass production plan already existed. Other projects, however, did result from this initial re-kindling. In the fall of 1939, Arnold wrote his old friend Charles Kettering, now vice-president of General Motors, wanting to develop “glide bombs” to be used if war came. What Arnold wanted was a device that could be used by the hundreds which might keep his pilots away from enemy flak barrages. Even though strategic airpower doctrine centered around precision, daylight, high-altitude bombing, Arnold was willing to sacrifice some level of accuracy in AAF bombing to minimize potential danger to his airmen--particularly in the last year of the war.
The legacy of these early “stand-off” weapons for today’s Air Force was clearly demonstrated during the Gulf War. Today’s Precision Guided Munitions (PGMs) have redefined the meaning of “mass” in terms of bombing effectiveness. The evolution of “Bug” technology into a lethal, long-range, stand-off capability is the realization of General Hap Arnold’s vision for these early pilotless weapons.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.