N23721

1999 Boeing 737-724

Fixed-wing, multi-engine · serial 28940

Valid registration

Registered with the FAA until Oct 31, 2029.

Registered owner

United Airlines Inc

Owner type: Corporation
Address: Attn: Treasurer Willis Tower 233 S Wacker Dr, Chicago, IL 60606
Fleet: 1,220 aircraft registered to this owner

Aircraft

Make and model: Boeing 737-724
Year built: 1999
Serial number: 28940
Type: Fixed-wing, multi-engine · Land
Engines: 2 × Turbofan · CFM Intl. CFM56 SERIES · 2,200 hp
Seats: 149
Weight class: 20,000 lb and over
Certification: Type certificated · Standard airworthiness (issued Mar 9, 1999)
Mode S code: A22539 (the transponder's ICAO address, used by ADS-B flight trackers)
Registered since: Mar 10, 1999 · last FAA action Sep 9, 2023

What a Boeing 737 Next Generation looks likePhoto of a Boeing 737 Next Generation, not this aircraft: 4300streetcar, CC BY 4.0, via Wikimedia Commons

Check the official record

This page mirrors the FAA's public registry file dated Oct 30, 2026. The FAA's own N-number inquiry is the official record, with the full owner address and documents.

Where is it now?

The registry doesn't show where an aircraft is flying. Flight trackers do, by tail number or Mode S code A22539: FlightAware or ADS-B Exchange. Some owners block tracking through the FAA's privacy programs.

Something wrong?

Owners update their registration with the FAA Aircraft Registry; changes appear here the day after the FAA publishes them. Email admin@whoownsthisplane.com about how this site shows a record.