I saw the following 59 aircraft at Chicago O'Hare (ORD) on Sunday, August 12, 2018:
A6-ETI 777-3FX(ER) Etihad Airways
B-1342 787-9 Dreamliner Hainan Airlines
B-7343 777-39P(ER) China Eastern Airlines
EI-EJH A330-202 Alitalia
EI-FNG A330-302 Aer Lingus
G-BYGC 747-436 British Airways
HB-JHK A330-343 Swiss
HL8042 777-3B5(ER) Korean Air Lines
HP-1719CMP 737-8V3(WL) COPA Airlines
JA734J 777-346(ER) Japan Airlines
JY-BAA 787-8 Dreamliner Royal Jordanian
LX-OCV 747-4R7F Cargolux Italia
N11547 ERJ-145-LR ExpressJet Airlines
N14904 ERJ-145-LR ExpressJet Airlines
N158GJ CRJ-702 Gojet Airlines
N161GJ CRJ-702 Gojet Airlines
N170GJ CRJ-702 Gojet Airlines
N171US A321-211 American Airlines
N204UA 777-222(ER) United Airlines
N260NN ERJ-175-LR (ERJ-170-200 LR) American Eagle
N312FR A320-251N(WL) Frontier Airlines
N34455 737-924(ER)(WL) United Airlines
N37462 737-924(ER)(WL) United Airlines
N419AW CRJ-200-ER Air Wisconsin
N438AW CRJ-200-ER Air Wisconsin
N45440 737-924(ER)(WL) United Airlines
N470ZW CRJ-200-ER Air Wisconsin
N48UA DC-8-61 United Aviation Services (UAS)
N522AE CRJ-701-ER American Eagle
N522VL A320-233(WL) Volaris
N525AE CRJ-702-ER PSA Airlines
N527EA CRJ-702-ER American Eagle
N57868 757-33N(WL) United Airlines
N651RW ERJ-170-SE (ERJ-170-100 SE) Shuttle America
N653RW ERJ-170-SE (ERJ-170-100 SE) Shuttle America
N658AE ERJ-145-LR American Eagle
N663AR ERJ-145-LR American Eagle
N66848 737-924(ER)(WL) United Airlines
N688AE ERJ-145-LR American Eagle
N699BR CRJ-200-ER SkyWest Airlines
N712JB A320-232 JetBlue Airways
N719SK CRJ-701-ER American Eagle
N731YX ERJ-175-LR (ERJ-170-200 LR) United Express
N73275 737-824(WL) United Airlines
N800AN 787-8 Dreamliner American Airlines
N805UA A319-131 United Airlines
N819AN 787-8 Dreamliner American Airlines
N840NN 737-823(WL) American Airlines
N846HK ERJ-145-LR Trans States Airlines
N899NN 737-823(WL) American Airlines
N907AN 737-823(WL) American Airlines
N922AN 737-823(WL) American Airlines
N930EV CRJ-200-ER SkyWest Airlines
N933EV CRJ-200-ER Atlantic Southeast Airlines (ASA)
N952AT 717-2BD Delta Air Lines
N955AN 737-823(WL) American Airlines
VQ-BWY 747-83QF Silk Way West Airlines
VT-ALX 777-300(ER) Air India
XA-VTA A320-214 Interjet