Daylight discs account for 13% of all sightings. Daylight discs with a strangeness of 1 or 2 basically match Vallee's FB1 flyby one category: a simple sighting of a UFO traveling in a straight line across the sky. These make up around 75% of daylight disc sightings. The only think to differentiate it from an aircraft, a bird, or other daytime object is that they appear different to the witness in terms of appearance or apparent speed from a conventional object. These may often simply be aircraft that are not recognized as such by the witness.
10% of all daylight discs are of strangeness 3, correlating with Vallee's MA1 category: they make maneuvers. These can include hovering, darting off towards the horizon or vertically at great speed, and making 90 degree-maneuvers with seemingly impossible rapidity. They can also include lazy terrain-following, seemingly barely-in-control wobbling and 'falling leaf' motion. In any case, they surely do not match the behavior of known aircraft.
And in many cases daytime discs simply do not look like crafted objects. Witnesses often state that the shape and color they are providing are just the closest approximation to something that was outside of their experience. It may be a mistake to think of them as machines. They may simply be the daytime manifestation of the glowing, maneuvering objects seen at night.
Daylight Discs Chronology
Daylight Discs by Location