The letters seem to be airport codes from left to right.
ORF = Norfolk International Airport - Norfolk, VA, USA
BEO = Belmont Airport - Newcastle, New South Wales, Australia
EWR = Newark International Airport - Newark, NJ, USA
UGC = Urgench Airport - Urgench, Karakalpakstan , Uzbekistan
UCA = Oneida County Airport - Utica, NY, USA
UHE = Uherske Hradiste Airport - Uherske Hradiste, Czech Republic
JSI = Alexandros Papadiamandis Airport - Skiathos, Greece
APE = San Juan Aposento Airport - San Juan Aposento, Peru
SLC = Salt Lake City International Airport - Salt Lake City, UT, USA
The clue says, "First Letters Then Numbers.
The "first letters" of the locations of each set of airports are N, U, and S.
At 5:26 in the video, fireworks are shot out in a group of 4, then 6, then 7.
Searching for N467US with the word disappearance yields the result, DB Cooper. N467US was the FAA registration of the plane in that heist.
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