The operational record
A compilation with stated technical limits
The Comando Aéreo de Defesa Aérea (COMDA), Brazil's Air Defence Command, forwarded its occurrence report on 2 June 1986. Brigadier José Pessoa Cavalcanti de Albuquerque signed it as interim commander. Its opening explains that time and specialist knowledge constrained the investigation and that the command restricted itself to an operational account. This defines the report's remit: it assembled information from controllers and intercepting pilots rather than conducting a complete scientific investigation. Covering letter and introduction, pp. 1–2.
The initial considerations describe radar systems whose primary purpose was air traffic control, manual intervention needed to maintain contacts, and returns too weak to support satisfactory tracking. Controllers therefore used their judgement and experience to direct aircraft towards reported contacts. The distinction between an indication on a display and a continuously tracked target is central to interpreting the subsequent account. A sequence of intermittent indications can suggest movement without establishing that every indication belongs to the same source.
The original report uses times marked “Z”, the aviation designation for UTC. The chronology below preserves that convention, including its transition into 20 May. It should not be read as a sequence of local clock times on 19 May.
The Santa Cruz visual account
First Lieutenant Kleber Caldas Marinho's personal report, dated 28 May 1986, identifies his aircraft as Jambock 17. He describes a light changing position relative to his aircraft and an onboard radar contact at approximately the same bearing, at a displayed range of 10–12 nautical miles. He also describes observing green, red and white colours, with white predominating. His account records an effort to interrupt his visual fixation to reduce night-vision illusion. Marinho report, pp. 1–2.
This is a specific report of correspondence, rather than the general claim that radar and visual observations occurred somewhere during the same night. It deserves separate treatment. The personal statement, however, contains no preserved radar plot sequence or optical record from which that association can be independently reconstructed. Its range belongs to the radar indication; assigning it to the visible light depends on the pilot's reported association.
Marinho's references to flight levels describe the aircraft's altitude during the observation. They cannot automatically be transferred to the light. A source seen above or below the aircraft requires a constrained distance and viewing geometry before its altitude can be calculated. Likewise, apparent position changes during an intercept combine the observer's movement with whatever movement the observed source may have had.
Anápolis acquisition and unsuccessful searches
Captain Armindo Souza Viriato de Freitas's Anápolis report identifies Jaguar 116 and describes repeated airborne radar acquisition without visual contact. He records his aircraft reaching Mach 1.05 during one approach, an increasing indicated separation and subsequent loss of acquisition. That Mach value describes the interceptor. Establishing the other source's speed would require the time history of range, relative direction and both trajectories. Anápolis personal reports, p. 5.
The same packet preserves negative results. Captain Rodolfo da Silva Souza, identified with Jaguar 98, reports unsuccessful visual and radar searches. His account describes difficulty determining a target's heading and speed through a relay from the ground station to the controlling position and then to the aircraft. Captain Júlio Cezar Rozemberg's report, identified with Jaguar 107, also records searches without visual or airborne radar contact. Anápolis packet, pp. 3–4.
These accounts show why a count of aircraft launched cannot serve as a count of independent confirmations. A null search does not identify the source of an earlier ground indication, because visibility, geometry and sensor coverage may differ. It nevertheless prevents the operation from being described as five pilots all confirming the same display.
Thirteen plots and an unconfirmed association
COMDA's account of the second Santa Cruz aircraft describes a red light at the position supplied by controllers. It subsequently records thirteen plots appearing behind the aircraft. A commanded turn produced neither visual nor onboard radar contact with those indications. Occurrence report, pp. 6–7.
The thirteen-plot passage is often an arresting part of the episode's narrative. The passage records a display indication, with an unsuccessful attempt at additional confirmation. Treating it as thirteen physical objects pursuing the aircraft would require a target association that this passage does not supply. It also should not be combined arithmetically with every light or return mentioned elsewhere: observations can overlap, recur or originate in different processes.
Documentary chronology
- 19 May 1986, 23:15Z: COMDA records notification of the São José dos Campos tower's visual observations and São Paulo approach radar reporting.
- 20 May, 00:08Z: The report records a civilian pilot's observations from PT-MBZ.
- 20 May, 00:39Z: The Santa Cruz alert aircraft is activated; Anápolis activation follows at 01:11Z.
- 20 May, 01:34Z–02:36Z: The report records two Santa Cruz and three Anápolis launches. Its final Anápolis launch is 02:36Z; the controller's separate account gives 02:35Z. The inspected records do not resolve the one-minute difference.
- 20 May, 02:37Z–03:30Z: The report records the five aircraft landing normally.
- 28 May 1986: Marinho's personal statement is dated. The Anápolis packet preserves controller and pilot accounts, but its handwritten covering-letter date remains unresolved here.
- 2 June 1986: COMDA forwards the compiled occurrence report and its concluding opinion.
- 25 September 2009: A retrospective government account dates the public release of that report to this day.
- October 2015: An archive release notice describes sixteen audio files, including eight recordings associated with the episode. Release metadata must be distinguished from a verified tape inventory. Government retrospective, archive release notice.
The command's assessment
COMDA's final considerations describe common characteristics, including radar echoes, varied velocities and abrupt changes of movement. The command inferred solidity and a degree of intelligence from the reported behaviour. Those conclusions belong to the institution that compiled the accounts. Reading them alongside the report's technical limitations and unsuccessful searches makes their inferential basis visible. Final considerations, pp. 7–8.
Several documentary stages repeat the same material. A personal statement incorporated into a command report and later summarised by an archive remains one underlying observation chain. Agreement between the versions can establish faithful transmission; it does not create another witness or another sensor measurement. The copies used here bear archive identifiers ARX.249, ARX.254 and ARX.256, but are hosted by FENOMENUM. Their host's interpretation is separate from the military documents.
Evidence assessment
The alert produced several different kinds of contact, and their association determines the physical interpretation. Marinho’s reported correspondence in bearing and Viriato’s radar-only sequence need different reconstructions. The former requires an independent visual/radar match; the latter requires target continuity and interceptor motion before changing range can become a performance estimate.
Unsuccessful searches restrict the command’s general synthesis by showing that the sorties did not produce uniform confirmation. They cannot identify contacts reported elsewhere. The retrospective total of 21 objects also needs a counting method that distinguishes repeated observations from distinct sources before it can describe a verified population.
Conventional lights and radar propagation are legitimate alternatives only when applied to specified intervals and equipment conditions. Conversely, treating all reports as one source requires synchronised positions and timing absent from the inspected packet. The records establish a significant military response with unresolved contacts, rather than a reproducible demonstration of one extraordinary physical origin across the operation.
Open questions
Synchronising the observations
The archive identifies surviving communications recordings. Time-stamped listening could establish when instructions, acquisitions and losses occurred, and whether a reported light remained at a corresponding bearing through a radar contact. The audio has not been inspected for this assessment. A recording's catalogue description cannot fill those gaps.
Recovering the measurement basis
Original radar material, if preserved and available, could clarify continuity, track identity and apparent changes of range. Instrument settings and environmental information would allow proposed radar explanations to be tested against particular returns. Pilot aircraft trajectories would also help separate a source's movement from changes produced by the intercept itself.
Further research
Witness record
Pilots whose statements were inspected
Marinho's signed statement describes his Santa Cruz observation. The Anápolis packet preserves the accounts of Viriato, Rodolfo da Silva Souza and Júlio Cezar Rozemberg. These are contemporary operational statements, rather than later interviews. Their different results remain distinct in the assessment.
Controller and institutional reporting
The Anápolis packet includes a controller statement signed by Paulo Roberto Ribeiro do Amaral. Albuquerque signed the command report as its institutional author; the document does not identify him as an eyewitness to the airborne encounters.
Source library
Operational reports reproduced online
- COMDA occurrence report, 2 June 1986; ARX.249: eight scanned pages covering the operational sequence, radar limitations and institutional conclusion.
- Marinho personal report, 28 May 1986; ARX.254: two scanned pages describing visual observations and reported airborne radar correspondence.
- Anápolis report packet; ARX.256: five scanned pages containing the covering letter, a controller account and three pilot reports. The covering letter's handwritten date remains unresolved in this assessment.
Official retrospective context
- Arquivo Nacional, Série Relatos Extraterrestres: identifies the episode within the archive's UFO holdings and reproduces a pilot-report image.
- Government of Brazil, Official UFO Night in Brazil, 20 May 2022: public account of the episode, official response and report release. Counts and attributed conclusions require comparison with their originating records.
- Arquivo Nacional audio release notice: documents the archive's description of the October 2015 release.
Further primary material
- ArquivoNacionalBrasil, recording 1: metadata identifies BR_DFANBSB_ARX_0_0_0692_m0001de0002. Its cover illustration concerns a separate Bauru report from 1968; it is not imagery of the 1986 episode. Recording content remains outside this assessment.