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Boeing 737-700 (737-724) · N21723 · United Airlines

Boeing 737-700 (737-724) illustration in United Airlines livery Illustrative image; it may differ from the actual aircraft.

Boeing 737-700 (737-724)

B737-28790Active
RegistrationUSN21723
Verified aircraft dataagainst the official civil aviation registerWhat does this badge mean?We checked that this aircraft’s registration, serial number and model match the official civil aviation register: FAA (United States), data as of Oct 8, 2026.That makes its identity more reliable. The verification expires after 12 months: if the register stops confirming it, the badge disappears.How we verify
OperatorUnited Airlines
3operators
2incidents
0accidents
19logbook years
0photos

Boeing 737-700 (737-724) built in 1999 in Renton. Operates for United Airlines. Previously flew for Continental Airlines and Continental Air Lines.

NewNearly newYoungMatureAgingOld
Old · 27 years · ≈ 89,100 flight hours (approx.)
Vuelopedia is a work in progress: it currently holds about 30% of the information we expect to have by the third quarter of 2027. Although we use only official, highly reliable sources, some aircraft data and history may still contain errors or inaccuracies. We work hard to clear every anomaly from the records using specialized verification tools.

Recent flights

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Technical data

ManufacturerBoeing
Engines2× 2 x CFMI CFM56-7B24
PropulsionTurbofan
Seats126 (F12 · Y114)
First flight1999
Built inRenton, Washington (EE. UU.)
Country of registrationEstados Unidos
OwnerUnited Airlines
MSN28790
Hex / ICAO 24-bitA1D63D
VerificationIdentity verified against the official register of FAA (United States) · Oct 8, 2026

The model · Boeing 737

Figures for the 737-800 variant, the most representative of the family

Length39.5 m129 ft
Wingspan35.8 m117 ft
Height12.6 m41 ft
Range5,436 km2,935 NMWith a typical passenger load
Cruise speed834 km/h450 ktMach 0.79
Service ceiling12,500 m41,011 ftIt flies above Everest (1.4 times its height)
Maximum take-off weight79,016 kg174,200 lb
Maximum payload37,603 kg82,900 lbIts 162 passengers with baggage would weigh about 16.2 t; the rest is fuel and cargo
Typical capacity162 passengersUp to 189 in a high-density layout
Endurance6 h 31 minAt cruise speed, non-stop

With its 5,436 km range, from Houston it could fly non-stop as far as:

LIMLima5,062 kmBOGBogota3,585 kmSEASeattle3,013 kmPTYTocumen2,856 kmJFKNew York2,278 km
Beyond its rangeSCLSantiago7,505 km

The type first flew in 1967 (59 years ago) · About 10,200 units built · Production ended in 2019

Figures for the type, not for this particular aircraft: each variant and each configuration changes something. They are shown in both systems used in aviation.

The full story of the Boeing 737 Compare this aircraft

Seating layout

12First
114Economy

126 seats in total

Airports

Where this aircraft has operated, by period · source BTS (EE. UU.)

2006–2011Continental Airlines · 6 years
Main base
IAHHouston6 years
Also flew to
EWRNewarkSNASanta AnaDCAWashingtonCLEClevelandLGANew YorkBOSBostonDFWDallas/Fort WorthAUSAustinORDChicagoSATSan AntonioPHXPhoenixMSYNew OrleansTPATampaRDURaleigh/DurhamATLAtlantaCLTCharlotteLAXLos AngelesPDXPortlandSFOSan FranciscoPBIWest Palm Beach/Palm Beach
2012–2025United Airlines · 13 years
Main base
ORDChicago6 yearsEWRNewark3 yearsIAHHouston2 yearsDENDenverGUMGuam
Also flew to
SNASanta AnaCLEClevelandIADWashingtonDCAWashingtonBOSBostonLGANew YorkDFWDallas/Fort WorthATLAtlantaSFOSan FranciscoSTTCharlotte AmalieSATSan AntonioBNANashvilleAUSAustinMSYNew OrleansJACJacksonRSWFort MyersMSPMinneapolisSANSan DiegoPITPittsburghCLTCharlotte

Flight logbook

Year-by-year activity · source BTS (EE. UU.)

2025
United Airlines · 1,093 flights during the year · base Chicago (ORD)
Main route of the year: Santa Ana (SNA) → Newark (EWR)
2024
United Airlines · 786 flights during the year · base Chicago (ORD)
Main route of the year: Santa Ana (SNA) → Newark (EWR)
82 days inactive
2023
United Airlines · 1,083 flights during the year · base Newark (EWR)
Main route of the year: Santa Ana (SNA) → Newark (EWR)
2022
United Airlines · 1,033 flights during the year · base Newark (EWR)
Main route of the year: Newark (EWR) → Santa Ana (SNA)
2021
United Airlines · 632 flights during the year · base Newark (EWR)
Main route of the year: Charlotte Amalie (STT) → Newark (EWR)
49 days inactive
2020
United Airlines · 550 flights during the year · base Chicago (ORD)
Main route of the year: New York (LGA) → Chicago (ORD)
2019
United Airlines · 969 flights during the year · base Chicago (ORD)
Main route of the year: Chicago (ORD) → Cleveland (CLE)
2018
United Airlines · 12 flights during the year · base Guam (GUM)
Main route of the year: Guam (GUM) → Saipan (SPN)
No reliable logbook records exist for this aircraft before 2006.

Aircraft chronology

1999
Built
Assembled by Boeing in Renton, Washington (USA).
Apr 6, 1999
Delivered to The Boeing Company
Delivered to The Boeing Company as N21723.
Apr 22, 1999
Transferred to Continental Airlines
Transferred to Continental Airlines.
Apr 22, 1999
Transferred to Continental Air Lines
Transferred to Continental Air Lines.
Sep 11, 2001
Grounded after 9/11
On September 11, 2001, the 737-724(WL) aircraft (registration N21723), operated by Continental Airlines, was in the news. Source: the FAA (United States).
What happened
On 11 September 2001, after the attacks with hijacked aircraft on the Twin Towers in New York and the Pentagon, the FAA ordered — for the first time in history — the complete closure of United States airspace (the SCATANA plan): all civil aviation was told to land immediately, and by midday the American sky was clear. Around 240 international flights bound for the United States were diverted to Canada — Operation Yellow Ribbon, with more than 30,000 passengers. Airspace reopened gradually from 13 September, by then under new security measures. Source: the FAA (United States).
Source: FAA
Jun 1, 2011
Transferred to United Airlines
Transferred to United Airlines.
Nov 30, 2011
News
On November 30, 2011, the 737-724(WL) aircraft (registration N21723), operated by Continental Airlines, was in the news. Source: United Airlines.
Source: United Airlines
Nov 28, 2023
Incident at Newark
On November 28, 2023, the Boeing 737-724(WL) aircraft (registration N21723), operated by United Airlines, was involved in an incident at Newark. Source: United Airlines.
Source: United Airlines
Oct 17, 2025
Incident at Chicago O'Hare Airport
On October 17, 2025, the Boeing 737-724(WL) aircraft (registration N21723), operated by United Airlines, was involved in an incident at Chicago O'Hare Airport (United States) due to a ground collision with another aircraft while taxiing. Source: United Airlines.
Source: United Airlines

Operators

1999-04-06
The Boeing Company
Registration N21723
—
The Boeing Company
Registration N1787B
1999-04-22
Continental Airlines
Registration N21723
1999-04-22
Continental Air Lines
Registration N21723
2011-06-01
United Airlines
Registration N21723

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Current position of the aircraft

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Real-time position via adsb.lol (ODbL license). There is a signal only while the aircraft is airborne and within coverage.

Cite

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This page was last updated on October 15, 2026

APA

Vuelopedia. (2026, October 15). Boeing 737-700 (737-724) · N21723 · United Airlines. Retrieved October 17, 2026, from https://vuelopedia.org/en/aircraft/B737-28790

MLA

“Boeing 737-700 (737-724) · N21723 · United Airlines.” Vuelopedia, Fundación Poderia, 15 Oct. 2026, vuelopedia.org/en/aircraft/B737-28790. Accessed 17 Oct. 2026.

Chicago

Vuelopedia. “Boeing 737-700 (737-724) · N21723 · United Airlines.” Fundación Poderia. Last modified October 15, 2026. https://vuelopedia.org/en/aircraft/B737-28790.

Harvard

Vuelopedia (2026) Boeing 737-700 (737-724) · N21723 · United Airlines. Available at: https://vuelopedia.org/en/aircraft/B737-28790 (Accessed: 17 October 2026).

BibTeX

@misc{vuelopedia_en_aircraft_b737_28790,
  author       = {{Vuelopedia}},
  title        = {{Boeing 737-700 (737-724) · N21723 · United Airlines}},
  publisher    = {Fundación Poderia},
  year         = {2026},
  date         = {2026-10-15},
  url          = {https://vuelopedia.org/en/aircraft/B737-28790},
  howpublished = {\url{https://vuelopedia.org/en/aircraft/B737-28790}},
  urldate      = {2026-10-17},
  note         = {Accessed 2026-10-17}
}

Wikipedia

{{cite web |url=https://vuelopedia.org/en/aircraft/B737-28790 |title=Boeing 737-700 (737-724) · N21723 · United Airlines |website=Vuelopedia |publisher=Fundación Poderia |date=2026-10-15 |access-date=2026-10-17 |language=en}}