The main classification of UFO reports in use is based upon one used by Dr J. Allen Hynek in his book "The UFO Experience" (Aberlard-Schuman 1972). It should be noted that many other classification systems have been devised by other researchers. Briefly the Hynek system is:
NL (nocturnal light): a simple visual sighting of a unidentified flying light seen at night.
ND (nocturnal disc): a simple visual sighting of a unidentified flying extended or structured light source seen at night. (This is an extension to Hynek's system).
DD (daylight disc): A simple visual sighting of a UFO with distinct shape seen during the day.
Radar Cases: UFOs detected by Radar.
Radar Visual Cases: UFOs observed visually whilst being simultaneously on radar. From Hynek's study these make up 1 to 2% of reports.
Close Encounters of the first kind (CE1, CEI): as first defined by Hynek, a CE1 is an observation of a UFO within 150 yards.
Close Encounters of the second kind (CE2, CEII): a UFO which leaves some form of physical evidence. Example: A burn where the UFO appeared to touch the ground or the finding of material of unknown makeup.
Close Encounters of the third kind (CE3, CEIII): a visual sighting of an occupant or entity associated with a UFO. An analysis by Hynek of 650 reports found only 1% to be CE3 (Close Encounters beyond the third kind are extensions to the basic Hynek system. Different authors have used the same designation to mean different things.)
Close Encounters of the fourth kind (CE4, CEIV): an abduction of an individual by an alien being or race.
Close Encounters of the fifth kind (CE5, CEV): a direct contact or communication with alien being or race. Example: Billie Meier with the Pleiadians, U.S.Govt. with the Greys, or channeling.
Vallee Classification System:
A system used to categorize the various types of UFO and paranormal experiences invented by Dr Jacques Vallee and is now used more often instead of the Hynek Classification System since it gives the reader a more detailed summary of a case. The categories are as follows...
AN RATING Classifies any anomalous behavior.
AN1 Anomalies which have no lasting physical effects. i.e. amorphous lights, unexplained explosions.
AN2 Anomalies which _do_ have lasting physical effects. i.e. poltergeists, materialized objects, areas of flattened grass, corn circles.
AN3 Anomalies with associated entities. i.e. ghosts, yetis, spirits, elves and other mythical/legendary entities.
AN4 Witness interaction with the AN3 entities. i.e. near-death experiences, religious miracles and visions, OBEs (out-of-body experiences).
AN5 Anomalous reports of injuries and deaths. i.e. SHC (spontaneous human combustion), unexplained wounds as well as permanent healing that results from a paranormal experience.
MA RATING Describes behavior of a UFO. It is analogous to the Nocturnal Light, Daylight Disk and Radar Visual Hynek classifications.
MA1 A UFO has been observed which travels in a discontinuous trajectory. i.e. vertical drops, manoeuvres or loops.
MA2 MA1 plus any physical effects caused by the UFO.
MA3 MA1 plus any entities observed on board. i.e. the airship cases of the late nineteenth century.
MA4 Manoeuvres accompanied by a sense of reality transformation for the observer.
MA5 A manoeuvre that results in a permanent injury or death of the witness.
FB RATING Fly-by rating.
FB1 A simple sighting of a UFO traveling in a straight line across the sky.
FB2 FB1 accompanied by physical evidence.
FB3 A fly-by where entities are observed on board (rare).
FB4 A fly-by where the witness experienced a transformation of reality into the object or its occupants.
FB5 A fly-by which the witness would suffer permanent injuries or even death. i.e. CASH/LANDRUM CASE.
CE RATING Close Encounter rating. Similar to the Hynek Close Encounter ratings.
CE1 UFO comes within 500 feet of the witness, but no after effects are suffered by the witness or the surrounding area.
CE2 A CE1 that leaves landing traces or injuries to the witness.
CE3 Entities have been observed on the UFO.
CE4 The witness has been abducted.
CE5 CE4 which results in permanent psychological injuries or death.
SVP RATING The all-important credibility rating. "Marks" out of four are given for the three categories of source reliability (first digit), site visit (second digit) and possible explanations (third digit). A rating of 222 or higher indicates the case was reported by a reliable source, the site has been visited and a natural explanation would require a major alteration of at least one parameter.
SOURCE RELIABILITY RATING
0 Unknown or unreliable source.
1 Report attributed to a known source of unknown or un-calibrated reliability.
2 Reliable source, secondhand.
3 Reliable source, firsthand.
4 Firsthand personal interview with the witness by a source of proven reliability.
SITE VISIT RATING
0 No site visit, or answer unknown.
1 Site visit by a casual person not familiar with the phenomena.
2 Site visited by persons familiar with the phenomena.
3 Site visit by a reliable investigator with some experience. 4 Site visit by a skilled analyst.
POSSIBLE EXPLANATIONS RATING
0 Data consistent with one or more natural causes.
1 Natural explanation requires only slight modification of the data.
2 Natural explanation requires major alteration of one parameter.
3 Natural explanation requires major alteration of several parameters.
4 No natural explanation possible, given the evidence.