SAINT-GERMAIN-EN-LAYE (78) 30.05.2020

On 30 May 2020, 10–20 minutes after Crew Dragon's launch, a witness at home in Saint-Germain-en-Laye (78) saw an airplane- or rocket-like craft pass rapidly in a straight line with a large flame at the rear. It was visible for no more than 1 minute. He gave its direction as west-southwest in the questionnaire and west-to-east in an email of 2 June 2020. He thought it was the Crew Dragon capsule. Falcon 9 launched with Crew Dragon from Cape Canaveral on 30 May 2020 at 21:22 French time. The first stage separated at T0 + 2 minutes 30 seconds and the second at T0 + 12 minutes. CNES's orbitography service confirmed that the capsule and launch-vehicle body were visible from France at about 19:45 UTC, with sunset lighting permitting observation. The capsule passed north of Saint-Germain-en-Laye, so it could not be the observed object. The launch vehicle had already performed passivation/deorbiting maneuvers before crossing France, preventing a precise orbit reconstruction, although some assumptions placed its second stage south of the town. GEIPAN initially accepted the latter explanation and classified the case A, “rocket stage.” After publication, a reader proposed an airliner instead. GEIPAN reopened the analysis, comparing the hypotheses and examining the video more closely to estimate the UAP's speed. West-southwest motion matched the witness's description under either hypothesis. Evidence favoring an airplane included its shape, characteristic double flashes visible when the video was enlarged, trails consistent with jet-engine contrails, and an actual aircraft in the indicated direction: a Boeing 777-243 (ER), London to Rome, flight AZ209 / AZA 20 LF, reported by Flightradar. Its time was later, 21:57 rather than the witness's 21:32–21:42, but GEIPAN considered this compatible with possible timing imprecision. The video speed estimate distinguished the explanations. The Moon appeared above the UAP, providing an angular reference. Its apparent width is 0.5°, and the UAP would cover that angle in about 0.5 seconds. For an aircraft at 10 km altitude, the source gives: - “angular velocity = angle in radians × time,” reproduced as written although the numerical calculation below divides distance by time; - for 360°: 2π × 10,000; - for 0.5°: 2π × 10,000 × 0.5/360 = 87 m; - speed = distance/time = 87/0.5 = 174 m/s, or 630 km/h, compatible with an airplane. For a rocket stage at 60–70 km altitude, the inferred speed would be about 1,050 m/s, which GEIPAN considered too low for a space object. This ruled out the rocket hypothesis relative to the aircraft explanation. The speed analysis therefore reinforced the conclusion that the object was very probably the Boeing 777 operating AZ209. GEIPAN revised its assessment and retained Category A with an airplane identification.