Jean-Charles Duboc, pilot, indicates in the "dimension" field:
"200 to 300 m
1/2 diameter of the moon."
The date of filling of the form is undoubtedly after 1997. The form is said to be a part of a "Synthesis of the report of investigation for the SEPRA" by Dominique Weinstein and Patrick Leprevost for the SEPRA, dated "2001 Weinstein/SEPRA".
Valérie Chauffour, co-pilot, indicates in the "dimension" field:
"Big size".
No angular size is indicated.
The date of filling of the form is undoubtedly after 1997. The form is said to be a part of a "Synthesis of the report of investigation for the SEPRA" by Dominique Weinstein and Patrick Leprevost for the SEPRA, dated "2001 Weinstein/SEPRA".
The author indicates:
"All appears normal, on January 28, 1994, on board Airbus A 300 of the Air France flight 3532, which took off Nice and moves towards London. But, suddenly, the three men [sic] of crew do not believe their eyes. At 01:14 p.m., at the vertical of Coulommiers, an object of dark color, in the shape of a bell, emerges on the left of the plane as if it had suddenly cut its road. Almost at once, the three men will testify, the object changed form to become a chestnut brown lens. It will remain nearly one minute at their height, before suddenly disappearing."
No angular size is indicated.
"One of these cases is particularly interesting. This case occurred on January 28, 1994, about 70 kilometers southeast of Paris, at a height of 11,700 meters, under excellent meteorological conditions. An object was first noticed by a steward who happened to be in the cockpit, and his observation was then confirmed by the copilot. The captain then saw the object. It was above the thick layer of altocumulus clouds at 10,500 meters. The captain described the object as resembling a gigantic disk (diameter about 1000 meters, thickness about 100 meters) with slightly fuzzy edges. The witnesses suddenly lost sight of the object when the edges appeared to go out of focus and the object disappeared.
No angular size is indicated.
The author indicates that he publishes what Jean-Charles Duboc told.
It is indicated there that first the steward saw an object in the sky and exclaimed "a weather balloon!", then the copilot also identified it as a weather balloon, then Jean-Charles Duboc indicates that having seen it the last, he rather thought of a plane banking of 45 degrees of slope before it has its wings horizontal, then thought that it was a rather strange object.
Jean-Charles Duboc then states that the excellent conditions of visibility and the presence of altocumulus clouds enabled him to estimate that the object was at 46 kilometers below [sic] the plane, at an altitude of 10.500 meters and in the direction 10 hours in the North-West practically at the vertical of Paris.
Jean-Charles Duboc then describes the object as having taken the shape of a bell with slightly vague contour which changed to a sort of brownish lens.
It is indicated that he managed to estimate its gigantic dimensions as being of 1000 meters in diameter [width] for 100 meters thickness [height] whereas an airliner at this distance would have been only a tiny dot. The object had neither wings neither control surface nor engine and could be seen under several angles during nearly one minute.
It is indicated that when it was passed on the left of the plane it was seen by the crew becoming suddenly transparent and disappearing without moving.
No angular size is indicated.
An insert in this magazine indicates that the observed phenomenon had "several tens of meters", affirming that the estimate of this size was made by the SEPRA according to radar data.
No angular size is indicated.
The article indicates that the steward and the copilot immediately identified the object as being a weather balloon and only the pilot sees in it a weird object but without sufficient certainty to submit an official UFO report on his own.
No angular size is indicated.
The report indicates that the steward present in the cockpit announces a phenomenon which appears to him to be a weather balloon, his observation is confirmed by the copilot, the pilot who sees it in his turn thinks that it is a plane in a 45 degrees slope. Very quickly, the three agree to note that what they see does not resemble anything. Because of its apparent diameter, they deduce that the object is of big size. The apparatus had changes in form, initially a brown bell, then a chestnut brown lens, then a quasi-instantaneous disappearance on the left of the plane.
The report indicates that an investigation by the CODA (Center of the Operations of Air Defense) of Taverny brought back to 250 meters the size of the observed apparatus by being basing themselves upon the precise distance of the crossing of the trajectories of the plane and the phenomenon.
No angular size is indicated.
"We arrived above Coulommiers when a steward who was in the cockpit noticed an object which seemed to him to be a weather balloon. This object was then seen by the copilot and myself a few moment afterwards."
"According to their description it seemed to have a variable form and to cross our path very quickly. I first of all identified it as a plane opposite us, at approximately 45 km (25 NM), at an altitude of approximately 10500 meters (25 NM) and on a slope close to 45°. I found this slope absolutely abnormal for aircraft do not do it at this altitude beyond 30° without a risk of losing lift. This object seemed to us then absolutely abnormal by its size which seemed huge, its dark red color and the fuzzy edges. I had the impression to observe a gigantic lens in manoeuver. It did not resemble anything we had seen in our flight career."
"This object, this phenomenon, remained motionless while we leave it on our left side always at the distance of approximately 45 km. We observed it during a good minute, conscious of seeing something absolutely abnormal. We continued to observe it when it gradually merged with the environment. We saw it becoming undefined, transparent, diluted in space. That was absolutely stunning."
And:
"I learned of the radar recording by CODA (Operational Center of Air Defense). There is a very curious characteristic for the trajectory of the UFO makes us almost collide. The minimal distance on the recording is less than 1 NM, that is to say 10 seconds of flight."
No angular size is indicated.
Jean-Charles Duboc indicates:
"The steward who was in the cockpit saw something which resembled a weather balloon, which cut our path. The copilot saw it too. I was the last to see it. I did not see it like that at all, myself, I saw a... what I identified as an enormous... enormous dark red lens with fuzzy edges."
No angular size is indicated.
[Recording not found yet.]
Jean-Charles Duboc indicates:
"The steward, who was in the cockpit, saw, er... an object in the shape of a balloon crossing our flightpath... A... The copilot saw it also, and myself, I was the last to see it and I saw what I identified as a gigantic red lens, er... evolving, above Paris. [Cut] We sees every day planes fly by in the sky, but when it is a machine which has the size of a steamer or a supertanker, that makes us a weird impression, I mean, you're not used to this. [Cut] We saw it disappearing, er, without moving, and that was utterly stunning, incredible, and... thus it was unimaginable."
No angular size is indicated.
Jean-Charles Duboc indicates:
"The steward which was in the cockpit, the copilot, then myself, we saw a... an absolutely enormous object passing in front of us and stopping at 25 [nautical miles] of our position. It had a dimension of two to three hundred meters, like a sort of very large dark red lens with fuzzy edges. We observed it during one or two minutes. We saw it becoming transparent and disappear."
No angular size is indicated.
"I saw it become transparent then disappear on the spot..."
The authors indicate that the steward chief of cabin announces an object on the left of the Airbus. "a weather balloon?" Jean-Charles Duboc thinks that it is rather a plane "in turn with 45 degrees banking", the copilot moved for better seeing and is on the left behind Duboc's seat and finally all the three agree to say that the phenomenon resembles nothing known. The shape of the object seems to be changing. It is at an approximate distance of fifty kilometers at the altitude of ten thousand five hundred meters, according to a layer of altocumulus to the background being used as reference mark. "Taking into account its apparent diameter there is no doubt that it is of big size..." According to Jean Charles Duboc it has initially the shape of a flattened bell which transforms into a dark red disc without control surface nor engine. The authors quote:
"... This object seemed to be a gigantic disc, that we could see under different angles."
"A huge size."
The authors indicate that it finally took the aspect of a lens before disappearing suddenly.
The authors indicate that the copilot says that it was a dark brown disc which changed form all the time by alternating clear and fuzzy contours, and which volatilized.
The authors quote the copilot as saying:
"I do not know if the object really disappeared or if it suddenly moved away at such a tremendous speed that the visual effect was the same for us..."
And:
"I really saw something weird."
The authors indicate that the pilots made drawings that show a slight difference in perception and which "essentials" remains the same however, indicated as like a kind of giant disc, of red color, which will change form. The authors indicate that the two pilots agree on the suddenness of disappearance.
The authors note that the crew had initially estimated that the object had one kilometers in length, size which was brought back to initially three hundred meters, then five hundred meters during the reconstitution by comparison in angular dimension, "(small finger held at arm's length)."
Jean Charles Duboc is the guest and says:
"It is a steward who was in the cockpit who saw this thing first which was apparently in his opinion a weather balloon, then it was the copilot, the young [?] copilot, who is pilot he [sic, she] too, Valerie Chauffour, and then it is I who saw it the last and in fact it had changed form, you see. And it had, according to me it had... you would believe, you would believe that it was a plane opposite us constantly inclined, of 45 degrees, but on the other hand it had a gigantic size since it was at 25 nauticals [nautical miles] approximately, since we very well saw the distances with the altocumuli clouds which were below, and we approximately estimated it as of several hundreds of meters."
Upon questioning "what did it look like approximately Mr. Duboc?":
"Ah well it was... As I saw it myself it was a gigantic dark lens er, red, you see, on er... that you saw... of profile, you see."
Upon questioning "so it had a discoid shape, then?"
"Yes more discoid, that's it, that's how I saw it, you see. And it was, er..."
Upon questioning "bigger or smaller than your plane?"
"Ah well it was... if you want we saw the distance very well you see, it was much larger. It was enormous actually, it had the size of a steamer ship, approximately."
Upon questioning "so it could have contained straightforwardly your own plane inside it?"
"Oh yes, very largely, it could have contained several 747, without problem. And, it made, I was auditioned afterwards by officers of the Air Force, studies at large were made, you see, it was of about three hundred meters in diameter."
On comment "that's huge.":
"Oh yes. it is definitely huge." [...]
No angular size is indicated.
Jean-Charles Duboc indicates:
"I saw a... what I identified as an enormous... enormous lens er... dark red with fuzzy edges."
No angular size is indicated.
Jean-Charles Duboc indicates:
"Above Coulommiers we saw a gigantic dark red saucer which was between 500 meters and 300 meters in diameter and which was at approximately 25 [nautical miles], that is nearly 45 kilometers. At our 10 o'clock, 10 o'clock 11 o'clock. Without movement, finally, it was tilted of 45 degrees, it took an horizontal position, and we sur.. surveyed it between one and two minutes."
Upon questioning "and you were the only one to see it?"
"Oh no, no, there was the co... myself, the copilot and a steward in the cockpit thus there are three indisputable witnesses. There was an excellent visibility, there was at least 150 kilometers of visibility, there were altocumulus and we saw very well. In a plane the distances are easily er, appraisable, much more than on the ground."
Upon questioning "what's the reaction when you see that?"
"I never wanted to submit a written report because, first, it was huge, it made 300 to 500 meters, and then, especially, it dematerialized in front of us [...] It disaggregated, dematerialized, it's like Star Trek, it's not..." [He is interrupted.]
Upon questioning "progressively?":
"No, no, in 10 or 15 seconds."
Jean-Jacques Vélasco then states that there was two minutes of visual observation on behalf of the crew, that a military or civilian plane at a distance of 40 kilometers appears the size of a point of ball point pen held at arm's length.
Jean-Jacques Vélasco indicates that it was requested separately from the pilot and to the copilot to what would the "dimension at arm's length" corresponds, he states:
"And they told us: 'the thumb!'"
"Because, they say, Mr. Duboc gave a size of "1/2 of the moon" (thus 0,15 arc minutes)
Full moon = 0,5° or 0,30 arc minute"
After reaction in [ta20], Eric Maillot corrects, 1/2 of the moon, i.e. 0.25°, are not 0.15 arc minutes but 15 arc minutes.
On March 24 2007, Jean-Charles Duboc published a comment on the website of the association "L'Observatoire Zététique," indicating:
"As an airline pilot, I was confronted to an observation of UFO, on January 28, 1994, above Paris, and I am part of the indisputable cases which were studied by Geipan."
"It is available at this address:
http://baseovnifrance.free.fr/afr3532.php
Unbelievable but true !..."
The URL indicated by Jean-Charles Duboc point to an unsigned web page giving again elements of [ta7].
In addition, the page's author indicates:
"Apparent size : 6mm (a quarter of the width of a thumb at arm's length)"
LL alerts on an error on the source [ta17]:
1/2 of the moon, i.e. 0.25°, are not 0.15 arc minutes as indicated in [ta17], but 15 arc minutes.
The page, about the size of the phenomenon, indicates that "the crew of the Air France flight observes a large brown - red disc of changing form and which seems of very big size."
No angular size is indicated.
| Ref.: | Type of source: | J.-C. Duboc: | V. Chauffour: | J.-J. Vélasco: | Others: |
|---|---|---|---|---|---|
| ta1 | Form. | 1/2 of the diameter of the moon. | N/A. | N/A. | N/A. |
| ta2 | Form. | N/A. | Nothing. | N/A. | N/A. |
| ta3 | Paris-Match magazine. | Nothing. | Nothing. | N/A. | Nothing. |
| ta4 | Article in the scientific journal JSE. | Nothing. | Nothing. | Nothing. | Nothing. |
| ta5 | VSD OVNIS Magazine. | Nothing. | Nothing. | N/A. | Nothing. |
| ta19 | Facteur X ufology magazine. | Nothing. | Nothing. | N/A. | N/A. |
| ta6 | Web page by Eric Maillot. | N/A. | N/A. | N/A. | Nothing. |
| ta7 | COMETA report. | Nothing. | Nothing. | N/A. | Nothing. |
| ta8 | Witness interview by ufologist. | Nothing. | N/A. | N/A. | N/A. |
| ta9 | Witness interview on TV. | Nothing. | N/A. | N/A. | N/A. |
| ta10 | Witness interview on TV. | N/A. | N/A. | N/A. | N/A. |
| ta11 | Witness interview on TV. | Nothing. | N/A. | N/A. | N/A. |
| ta12 | Witness interview on TV documentary. | Nothing. | N/A. | N/A. | N/A. |
| ta13 | Book by investigator JJV. | Uncertain, small finger at arm's length. | Uncertain, small finger at arm's length. | Small finger at arm's length. | Uncertain, small finger at arm's length. |
| ta14 | Witness interview, ufology radio show. | Nothing. | N/A. | N/A. | N/A. |
| ta15 | Witness interview, ufology radio show. | Nothing. | N/A. | N/A. | N/A. |
| ta16 | TV show. | Nothing. | N/A. | The thumb at arm's length. | N/A. |
| ta17 | Eric Maillot. | N/A. | N/A. | N/A. | 1/2 of the moon. |
| ta18 | Web page indicated by witness. | 6mm, a quarter of the thumb at arm's length." | N/A | N/A | N/A |
| ta21 | GEIPAN web page. | Nothing. | Nothing. | N/A. | Nothing. |
| Id: | Topic: | Severity: | Date noted: | Raised by: | Noted by: | Description: | Proposal: | Status: |
|---|---|---|---|---|---|---|---|---|
| 1 | Data | Severe | May 5, 2007 | Patrick Gross | Patrick Gross | No investigation report available. | Help needed. | Open. |
| 2 | Ufology | Severe | May 5, 2007 | Patrick Gross | Patrick Gross | Among 3 witnesses, only 1 provides an angular size. | Help needed. | Open. |
| 3 | Ufology | Severe | May 5, 2007 | Patrick Gross | Patrick Gross | No information on method of estimate of angular size. | Help needed. | Open. |
Mr. Jean-Charles Duboc indicated an angular size twice: the first time by filling an official ufology sighting report form, indicating a size equivalent to that of half of the apparent size of the moon [ta1], the second time by quoting a web page about the sighting as indicating an angular size corresponding to the apparent size of a quarter of the thickness of the thumb at arm's length, approximately 6 millimeters [ta18], which is consistent with his first indication. I did not find any contradictory statement of the witness on this matter.
No angular size was indicated directly by the two other witnesses, in the sources that are available to me, which is very unfortunate. A case with multiple witnesses is not really a multiple witnesses case if only one witness provides information.
To get witnesses to fill a "Dimension:" field on a form is in no way a valid method. Here, only Jean-Charles Duboc realized that an angular size was the only information that makes sense, the copilot providing as answer "very big", which is quantitatively meaningless.
Mr. Jean-Jacques Vélasco, at the time of the SEPRA within the CNES, indicated in his 2004 book an angular size corresponding to the apparent size of a small finger at arm's length, i.e. approximately 18 millimeters. In a general public TV show in 2007, in the presence of the witness Jean-Charles Duboc, he indicates in an angular size corresponding to the apparent size of a thumb at arm's length, i.e. approximately 25 mm.
This is a rather odd situation, in which the angular size given initially by the witness had been tripled, then quadrupled.
The manner in which the size angular was measured, or estimated, is indicated nowhere by anybody. A request that I made on this matter did not receive an effective answer.
At the best of what can be deduced on the matter, it seems that the angular size of the UFO was about that of half of full moon, that is to say about 15 arc minutes.
If the UFO were indeed at a 46 kilometers distance, it corresponds to a real width of 200,70 meters. This is a figure which appears in several sources, but itself prone to variations from one source to another.
The following table gives various examples of an approximate real dimension of a 15 arc minute at various distances:
| For a distance of: | The object's width would be at: |
|---|---|
| 100 meters | 45 centimeters |
| 1 kilometer | 4.30 meters |
| 5 kilomètre | 21 meters |
| 10 kilometers | 43 meters |
| 15 kilometers | 65 meters |
| 20 kilometers | 87 meters |
| 30 kilometers | 130 meters |
| 40 kilometers | 175 meters |
| 46 kilometers | 200 meters |
| 50 kilometers | 218 meters |
| 80 kilometers | 350 meters |
| 100 kilometers | 436 meters |
| Version: | Created/changed by: | Date: | Change description: |
|---|---|---|---|
| 0.1 Draft | Patrick Gross | March 27, 2007 | Creation: [ta1] to [ta9] and [ta11] to [ta17] |
| 0.1 Draft | Patrick Gross | March 27, 2007 | Communicated to the members of the Internet discussion list "L'Observatoire Zététique" for comments, corrections, possible additional information. |
| 0.2b Draft | Patrick Gross | March 28, 2007 | Addition for [ta1] and [ta2] of the paragraph: "The date of filling of the form is undoubtedly after 1997. The form is said to be a part of a "Synthesis of the report of investigation for the SEPRA" by Dominique Weinstein and Patrick Leprevost for the SEPRA, dated '2001 Weinstein/SEPRA'." Addition of [ta18]. Addition of [ta19] as unavailable source. All these additions were made following information by Eric Maillot after the day before communication to the members of the discussion list "L'Observatoire Zététique". |
| 0.2c Draft | Patrick Gross | March 28, 2007 | Addition de [ta20]. |
| 0.2d Draft | Patrick Gross | April 1, 2007 | Addition of content for [ta19]. |
| 0.2e Draft | Patrick Gross | April 29, 2007 | Addition of the original version in English for [ta4], and addition of [ta21]. |
| 0.2f Draft | Patrick Gross | May 6, 2007 | Addition of the Summary Table, the List of Issue and the Synthesis. Creation of the English version of the document. |
| 0.3 Productive | Patrick Gross | May 6, 2007 | First announced publication on the author's website www.ufologie.net in the "site updates" section and publication URL defined. Information thereof sent to the discussion list "L'Observatoire Zététique" for possible late comments. |
| 1.0 Productive | Patrick Gross | June 21, 2007 | Conversion from HTML4 to XHTML strict. |
