The Brazilian Air Force formed SIOANI in the late 1960s to document sightings nationwide. In 1977, Operation Prato investigated wave activity around Colares, producing reports and photographs that were later declassified.12345
Historical overview
The Sistema de Investigação de Objetos Aéreos Não Identificados (SIOANI) emerged within the IV Comando Aéreo Regional in March 1969 under Brigadeiro José Vaz da Silva. Conceived as a nationwide intelligence grid, it coordinated Central (CIOANI), Regional (ZIOANI), and Field (NIOANI) units that catalogued sightings, collected material evidence, and submitted technical and psychiatric assessments. Although funding was modest, the network mobilised volunteer military specialists, academics, and vetted civilians, producing two official boletins and roughly 100 detailed case files before budgetary realignment ended the effort in 1972.
In 1977 Colonel Protásio Lopes de Oliveira authorised Operação Prato, a rapid-response inquiry into persistent nocturnal lights and alleged beam injuries in Pará. Captain Uyrangê Hollanda led forty-plus sorties that generated 2 000 + photographs, 16 h of film, and daily logs later summarised in a 179-page report. The mission ended abruptly in December 1977, yet its archives—together with SIOANI's—were classified as confidencial for decades.12
Founding mandate
The Air Force framed both initiatives as air-space security measures during the Cold War. Orders from the Ministério da Aeronáutica directed investigators to:
- confirm or refute hostile technological intrusions
- assess potential hazards to civil aviation
- preserve physical and testimonial data for scientific examination
Key personnel
Principal archives and casework
SIOANI recorded 70 official cases (1968-1969) covering close-encounter reports such as the Maria Cintra contact in Lins and multiple landing-trace events in Minas Gerais and São Paulo. Statistical tables reveal most observations occurred at night in urban settings with witnesses of diverse education levels.
Operação Prato documented sustained luminous phenomena over Colares, including beam emissions correlated with physiological effects reported by residents. Instrument packages — Geiger counters, spectro-photometers, tele-lenses — registered electromagnetic anomalies, yet the final brief to Brasília offered no explanatory model.
Declassification and legacy
Current scholarship regards these collections as the most rigorous governmental UFO records in Latin America, offering raw data for aerospace safety studies and sociological analysis of extraordinary-claim testimony.