On 15 May 1968, Spain’s air-defence organisation handled reports of unusual objects over the Madrid and Barcelona areas. Aircraft were asked to investigate, pilots proposed balloons and a passenger’s colour film entered an administrative chain that later reviewers could not complete. The released dossier treats the two areas as different observations, not one object crossing Spain.
The strongest documented explanation is stratospheric balloons. A later Air Force review connected the descriptions with French CNES launches, while supplementary correspondence used firmer language about the Catalan object. The outcome here is Possibly Explained for the combined record: the balloon explanation has concrete support, but the release does not preserve a complete identification trail or the missing film.
A telephone report over Madrid
The contemporary air-defence narrative begins at about 10:30Z with a call from an employee of the nuclear-energy organisation at Moncloa. Asked to inspect the object through binoculars, the caller described what seemed to be three parallel bodies. The report records an estimated height, but supplies no instrument measurement establishing that estimate.
An attempt to locate it through Matador radar did not succeed. The object was nevertheless visible from Torrejón. The tower was asked to examine it through binoculars, and its officer described it as a sounding balloon on visual appearance alone.
That is an important distinction within the source. Madrid’s initial account combined a visual observation and a failed radar search. It should not be advertised as a confirmed visual-radar target merely because radar contact appears elsewhere in the same dossier.
The Barcelona-area radar report
EVA 4, identified in the original narrative as Samba, separately reported a radar contact in the Barcelona area and asked to use fighters already participating in a training mission to examine it. Airline aircraft bound for Barcelona were also said to have reported an object to civil control.
The training aircraft did not identify it. The account gives problems coordinating heights and insufficient fuel as reasons. The later supplementary reply likewise says the formation had to return because its fuel was practically exhausted.
The main release’s summary reproduces an indicated height of 3,000 feet for this radar contact. Other parts of the combined response concern a high object that fighters could not approach clearly. The file does not supply a fully correlated plot resolving every altitude and every aircraft’s observation into one target history.
Keeping the Barcelona report separate from Madrid avoids creating a single object with all the disparate properties in the packet. The later analyst explicitly calls them two observations with similar characteristics at approximately the same time.
Fighters sent to investigate
As further information reached control, an identification scramble with filming equipment was ordered. A pair of United States Air Force F-100s also took off under its own command with the same purpose. The original narrative says the object’s height prevented a clear identification and usable filming, although the pilots thought it resembled a meteorological balloon.
The account does not preserve a successful close approach revealing a solid craft. Nor does the failure to obtain film demonstrate that the object deliberately evaded the fighters. The released narrative describes an operational limitation and an attributed visual assessment.
Some later claims alleged dramatic vertical motion during the interception. The supplementary 1969 correspondence explicitly rejected the rumour of large vertical displacements. That denial is part of the record and should accompany the more spectacular allegation, rather than being omitted from a reconstruction.
The passenger’s film
The contemporary military account then reports information passed through Madrid control from a DC-9. A passenger had taken colour footage and described an appearance of three parallel spherical bodies. The text says the commander had already taken custody of the film and that the passenger willingly cooperated with its transfer to the authorities.
The packet also includes press material concerning the inaugural Iberia service between the Canaries, Málaga and Paris. This identifies the filmer as Alfredo González Retuerce and describes the crew and passengers’ interest. The newspaper material is an enclosed account, not an independent Air Force technical analysis of the film.
The sources do not agree neatly over the flight’s direction and the reported viewing area. The operational narrative describes a Paris-to-Málaga aircraft and a position northeast of Madrid; the press account describes the inaugural northbound service and an observation near the Sierra Cebollera/Logroño area. The released pages do not settle that mismatch.
The later review says the film did not reach the relevant Air Staff office and was not in the dossier. Attempts to locate it for the release were unsuccessful. The forwarding paperwork, however, says both an account and film were sent. The surviving chain therefore contains a gap, rather than a film available for fresh examination.
That gap cannot establish what the images showed, who last possessed them or why they became unavailable. Later criticism of the film’s retention is a separate interpretation; it does not recover the footage or prove the nature of the photographed object.
The CNES balloon explanation
The October 1992 review considered trajectory, speed and witness impressions compatible with stratospheric balloons. It listed launches from Aire-sur-l’Adour in France on 13 and 14 May: one on the thirteenth and two on the fourteenth, with stated launch times and volumes.
The reviewer also described large tetrahedral balloons used by CNES and compared their appearance with descriptions from the broader 13–17 May sighting period. Metallic brightness, slow or absent apparent motion, and pyramidal or multi-part comparisons were offered as supporting similarities.
These are specific reasons to take the explanation seriously. They are stronger than simply saying that balloons exist. However, the table identifies launches regarded as probable candidates; the release does not provide a complete trajectory reconstruction assigning each observer’s object to a particular launch.
The reviewer also cautioned against treating the difference between one radar detection and another non-detection as decisive. That is an assessment within the file, not a rule that radar evidence never matters. The quality and correlation of the particular reports remain the relevant questions.
What the supplementary file adds
The separately released 680515 Bis packet preserves a private enquirer’s April 1969 letter and the subsequent official response. The enquirer asked whether reports of radar tracking, fighter launches and extraordinary vertical movement had any official basis.
The June 1969 reply says the Catalan object had subsequently been confirmed as a sounding balloon. It also rejects the vertical-motion rumour and explains the training formation’s fuel limitation. This firmer conclusion is reported as the authority’s statement, alongside the later main review’s more qualified balloon hypothesis.
The supplementary packet is therefore read with the main file as one canonical case. It is not another sighting in 1969 and not a second addition to the case library. Its release date in 1996 also belongs to the paperwork, not the incident.
Dates, assessment and map reference
The catalogue and cover of the main file say 13 May, while the original operational narrative, forwarding letter and dossier number 680515 support 15 May. This case uses the fifteenth and preserves the discrepancy. A later index also misdates the original May report by a year; the actual signed and stamped document is from 1968.
Possibly Explained reflects the well-supported balloon interpretation, with firmer official language for the Catalan observation but missing film and incomplete correlations across the whole packet. The radar tag applies to the Barcelona report only. The orb tag records the relayed passenger description of spherical bodies; it does not assert verified spheres or a single vehicle connecting the two cities.
Approximate map area: 41.39, 2.16, a rounded Barcelona city reference from GeoNames. It anchors one principal reporting area in the combined Madrid–Barcelona dossier. It is not an object position, a reconstructed balloon track or a midpoint representing every observation; the Madrid and airline accounts occurred elsewhere.
Read Biblioteca Virtual de Defensa, main dossier 680515 and its ten-page release, especially physical pages 2–3 and 5–8. Compare 680515 Bis, particularly its original 1969 reply on physical page 6. The GeoNames Barcelona record supplies the locality coordinates. Original pages, the main-file image licence and the documentary discrepancies were checked on 13 November 2026.