Vallee system

Jacques Vallee has devised a UFO classification system which is preferred by many UFO investigators over Hynek's system as it is considerably more descriptive than Hynek's, especially in terms of the reported behavior of UFOs.

Type I (a, b, c, d): Observation of an unusual object, spherical discoidal, or of another geometry, on or situated close to the ground (tree height, or lower), which may be associated with traces - thermal, luminous, or mechanical effects.

1. On or near ground.
2. Near or over body of water.
3. Occupants appear to display interest in witnesses by gestures or luminous signals.
4. Object appears to be "scouting" a terrestrial vehicle.

Type II (a, b, c): Observation of an unusual object with vertical cylindrical formation in the sky, associated with a diffuse cloud. This phenomenon has been given various names such as "cloud-cigar" or "cloud-sphere."

1. Moving erratically through the sky.
2. Object is stationary and gives rise to secondary objects (sometimes referred to as "satellite objects").
3. Object is surrounded by secondary objects.

Type III (a, b, c, d, e): Observation of an unusual object of spherical, discoidal or elliptical shape, stationary in the sky.

1. Hovering between two periods of motion with "falling-leaf" descent, up and down, or pendulum motion.
2. Interruption of continuous flight to hover and then continue motion.
3. Alters appearance while hovering - e.g., change of luminosity, generation of secondary object, etc.
4. "Dogfights" or swarming among several objects.
5. Trajectory abruptly altered during continuous flight to fly slowly above a certain area, circle, or suddenly change course.

Type IV (a, b, c, d): Observation of an unusual object in continuous flight.

1. Continuous flight.
2. Trajectory affected by nearby conventional aircraft.
3. Formation flight.
4. Wavy or zig-zag trajectory.

Type V (a, b, c): Observation of an unusual object of indistinct appearance, i.e., appearing to be not fully material or solid in structure.

1. Extended apparent diameter, non-point source luminous objects ("fuzzy").
2. Starlike objects (point source), motionless for extended periods.
3. Starlike objects rapidly crossing the sky, possibly with peculiar trajectories.

Source: 1. Jacques and Janine Vallee: Challenge To Science: The UFO Enigma, LC# 66-25843

Conspiracy theories