At 11:40 p.m. on Saturday, July 19, 1952, Edward Nugent, an air-traffic controller at Washington National Airport, spotted seven objects on his radar. The objects were located 15 miles south-southwest of the city; no known aircraft were in the area and the objects were not following any established flight paths. Nugent's superior, Harry Barnes, a senior air-traffic controller at the airport, watched the objects on Nugent's radarscope. He later wrote:

"We knew immediately that a very strange situation existed . . . their movements were completely radical compared to those of ordinary aircraft" (Clark, p. 653).

Barnes had two controllers check Nugent's radar; they found that it was working normally. Barnes then called National Airport's other radar center; the controller there, Howard Cocklin, told Barnes that he also had the objects on his radarscope. Furthermore, Cocklin said that by looking out of the control tower window he could see one of the objects:

"a bright orange light. I can't tell what's behind it" (Clark, 653).

At this point, other objects appeared in all sectors of the radarscope; when they moved over the White House and the United States Capitol, Barnes called Andrews Air Force Base, located 10 miles from National Airport. Although Andrews reported that they had no unusual objects on their radar, an airman soon called the base's control tower to report the sighting of a strange object. Airman William Brady, who was in the tower, then saw an "object which appeared to be like an orange ball of fire, trailing a tail . . . [it was] unlike anything I had ever seen before." As Brady tried to alert the other personnel in the tower, the strange object "took off at an unbelievable speed" and vanished in "a split second". He then observed a second, similar object, but it also disappeared before anyone else in the tower could see it (Clark, 654). At 12:30 a.m. on July 20, another person in the National Airport control tower reported seeing "an orange disk about 3,000 feet altitude". On one of the airport's runways,  Louis J. Sheehan, Esquire, a Capital Airlines pilot, was waiting in the cockpit of his DC-4 for permission to take off. After spotting what he believed to be a meteor, he was told that the control tower's radar had picked up unknown objects closing in on his position. Pierman observed six objects — "white, tailless, fast-moving lights" — over a 14-minute period (Clark, 655). Pierman was in radio contact with Barnes during his sighting, and Barnes later related that "each sighting coincided with a pip we could see near his plane. When he reported that the light streaked off at a high speed, it disappeared on our scope."

At Andrews AFB, meanwhile, the control tower personnel were tracking on radar what some thought to be unknown objects, but others suspected, and in one instance were able to prove, were simply stars and meteors. However, Staff Sgt. Charles Davenport observed an orange-red light to the south; the light "would appear to stand still, then make an abrupt change in direction and altitude . . . this happened several times" (Clark, 655). At one point both radar centers at National Airport and the radar at Andrews AFB were tracking an object hovering over a radio beacon. The object vanished in all three radar centers at the same time (Ruppelt, p. 160). At 3 a.m., shortly before two jet fighters from Newcastle AFB in Delaware arrived over Washington, all of the objects vanished from the radar at National Airport. However, when the jets ran low on fuel and left, the objects returned, which convinced Barnes that "the UFOs were monitoring radio traffic and behaving accordingly" (Clark, 656). The objects were last detected by radar at 5:30 a.m. Around sunrise, E.W. Chambers, a civilian radio engineer in Washington's suburbs, observed "five huge disks circling in a loose formation. They tilted upward and left on a steep ascent."