The Montserrat "Burning Plane": Spanish Air Force File 710223

Montserrat. A mountain monastery outside Barcelona, later known as a "UFO mountain" with monthly sky-watches on the 11th. In February 1971 its abbot became the first witness in a confidential Spanish Air Force file.

Tuesday, 23 February 1971. The sun had just set. At 19:15 the Abbot of Montserrat saw a spectacular fan of apparently white smoke, opening at about 60°, moving toward the ground. The abbot judged it to be about 100 km to the north, toward the Pyrenees.

At Monistrol de Montserrat, a Guardia Civil officer saw a luminous point, motionless at first as its smoke grew. Then it moved west, and the officer sketched it. An artillery captain and 43 men of CIR No. 10 saw a great fan and a trail that fell in S-curves and vanished before reaching the ground. A soldier of CRIM No. 3 watched a globe of light fall almost vertically, zigzagging a little, for about 5 minutes, and its trail stayed for 10 more.

The aircrews saw it too. Iberia IB-867 reported a very large trail slightly north of Lérida. Iberia IB-841 asked Barcelona control about crossing traffic about 20 NM away. There was none. On the flight from Mahón to Barcelona, the head of Menorca airport described a very clear, symmetrical trail, well above their level.

The strangest account came from the sea. About 25 NM north of San Sebastián, at about 19:00, the captain of a fishing boat saw a large silver jet with a spike on its nose. It fell burning into the sea about 200 metres from the boat.

The captain steered to the spot. A ring of fire lay on the water. It quickly went out. There was no wreckage.

The Spanish Air Force file carries reference 710223. An Air Force lieutenant colonel of the Third Air Region, whose name is redacted, gathered about 44 statements, weather reports and sunset times. The sky had been mostly clear. The 71 page report, dated 13 April 1971 in Zaragoza, concluded, in translation: "In view of all the above, the real existence of the phenomenon that is the subject of this report is evident."

The report went further. It states the event was identical to one seen over central and southern France and northern Italy, and that it coincided with the launch of a Tibère rocket from the Centre d'Essais de Biscarrosse, in Landes, during operation Electre. Sketches from the Société d'Astronomie Populaire de Toulouse matched the Spanish drawings exactly. Fragmenting meteorites and satellite re-entry were noted as secondary possibilities.

The Tibère was a three-stage ONERA re-entry test rocket, 14.5 m long, that flew only twice from Biscarrosse. The first flight was on 23 February 1971, reaching 150 km. A twilight launch, its high trail still lit by the sun while the ground lay in darkness, fits the fan of white smoke, the S-shaped trail and the reports across three countries. The fishing captain's silver jet remains the outlier. The investigating officer never called it a misidentification.

The file was declassified in October 1993 and has been online since 2016. Vicente-Juan Ballester Olmos advised on the wider Air Force declassification. In 2023 Gonzalo Araluce of Vozpópuli retold it as the UFO file that startled a group of Catalan monks, presenting it as unresolved and leaving out the rocket. It sits in the same Defence Library collection as the Manises incident.