The whirring of a low-flying Soviet Union-era war plane signalled Russia's uninvited arrival to NATO's biggest military exercise since the end of the Cold War.
"It's a long-range maritime patrol reconnaissance plane," said one fascinated marine after casting an expert eye over the visitor.
Although he had seen plenty of images of the aircraft, this was the first time he had seen it live, so to speak.
Russia has already made clear its displeasure at NATO's Trident Juncture exercises, the largest by the alliance since the end of the Cold War.
They warned that the two-week long exercise, which it sees as an anti-Russian show of force, would not go unanswered.
Last week, Moscow announced plans to test missiles in the region.
According to Avinor, the public operator of most civil airports in Norway, Russia sent a NOTAM (Notice to Airmen) about the missile tests November 1-3 in the Norwegian Sea.
Any missile testing "will not change the plan of our exercise," NATO Secretary General Jens Stoltenberg said on Wednesday.
"We have not seen anything resembling a missile test, or even ships or aircraft in the area that would be relevant to documenting or monitoring missile testing," said Robert Aguilar, captain of the USS Mount Whitney.