ICAO: A12AE4
Owner: UNITEDAIRLINES
Flt: UAL503 N17431 B39M BOS-ORD
Time: 2026-03-28 11:13:25 EDT
Min Alt: 13125 ft
Min Dist: 1.2 nm (85deg E)

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ICAO: A44983
Owner: UNITEDAIRLINES
Flt: UAL503 N37555 B39M BOS-ORD
Time: 2026-03-24 11:14:33 EDT
Min Alt: 15950 ft
Min Dist: 1.2 nm (90deg E)

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ICAO: A448D3
Owner: UNITEDAIRLINES
Flt: UAL503 N37504 B39M BOS-ORD
Time: 2026-03-18 11:21:14 EDT
Min Alt: 13150 ft
Min Dist: 1.2 nm (85deg E)

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ICAO: A12AEB
Owner: UNITEDAIRLINES
Flt: UAL503 N17438 B39M BOS-ORD
Time: 2026-03-17 11:14:45 EDT
Min Alt: 4050 ft
Min Dist: 0.5 mi (98deg E)

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ICAO: A12AEA
Owner: UNITEDAIRLINES
Flt: UAL503 N17437 null BOS-ORD
Time: 2026-03-14 11:19:36 EDT
Min Alt: 14225 ft
Min Dist: 1.2 nm (78deg ENE)

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ICAO: AA7F27
Owner: UNITEDAIRLINES
Flt: UAL503 N77584 B39M BOS-ORD
Time: 2026-03-12 11:46:23 EDT
Min Alt: 4400 ft
Min Dist: 0.5 mi (98deg E)

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Planefence ICAO: A0B821
Flt: UAL503 UNITEDAIRLINES RDU - EWR
First seen: 2025-07-29 23:42:00 EDT
Min Alt: 1075 ft MSL
Min Dist: 1.06 mi
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Planefence ICAO: A55FA2
Flt: UAL503 UNITEDAIRLINES RDU - EWR
First seen: 2025-07-19 23:37:40 EDT
Min Alt: 1125 ft MSL
Min Dist: 1.08 mi
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Map of the St. Louis area showing the position and track of the aircraft described in the post.

🇺🇸 N853UA - Airbus A319 131 - United Airlines UAL503/UA503 (MSY-ORD-CMH) - 4.3 mi away @ 36000 ft, heading NNE at 532 mph. Spotted 25x before! [12:05:38 PM CST] #ABB440 #N853UA #A319 #UNITED #UAL503 #UA503 #ADSB #ADSBbot