Flight WN851
Southwest Airlines flight WN851
Looking for WN851 in the air…
Houston (HOU) to Chicago (MDW)
Historically, this flight arrives 15+ minutes late 16% of the time, and when it is late the delay averages 48 minutes. It was cancelled 1.6% of the time.
- On-time arrivals
- 84.1%
- Less than 15 minutes late
- Cancelled
- 1.6%
- Of scheduled flights
- Average delay when late
- 48 min
- Flights arriving 15+ minutes late
- Flights tracked
- 64
- Scheduled flights in the period
What caused the delays
- Air traffic control & airport 77%
- Airline (crew, maintenance, cleaning) 23%
- Late-arriving aircraft 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Burbank (BUR) to Sacramento (SMF)
Historically, this flight arrives 15+ minutes late 20% of the time, and when it is late the delay averages 48 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 80.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 48 min
- Flights arriving 15+ minutes late
- Flights tracked
- 60
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 79%
- Airline (crew, maintenance, cleaning) 17%
- Air traffic control & airport 3%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Baltimore (BWI) to Boston (BOS)
Historically, this flight arrives 15+ minutes late 22% of the time, and when it is late the delay averages 57 minutes. It was cancelled 5.2% of the time.
- On-time arrivals
- 78.2%
- Less than 15 minutes late
- Cancelled
- 5.2%
- Of scheduled flights
- Average delay when late
- 57 min
- Flights arriving 15+ minutes late
- Flights tracked
- 58
- Scheduled flights in the period
What caused the delays
- Airline (crew, maintenance, cleaning) 60%
- Late-arriving aircraft 29%
- Air traffic control & airport 11%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Nashville (BNA) to Denver (DEN)
Historically, this flight arrives 15+ minutes late 39% of the time, and when it is late the delay averages 63 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 60.7%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 63 min
- Flights arriving 15+ minutes late
- Flights tracked
- 28
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 70%
- Air traffic control & airport 20%
- Airline (crew, maintenance, cleaning) 9%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Dallas (DAL) to Tucson (TUS)
Historically, this flight arrives 15+ minutes late 5% of the time, and when it is late the delay averages 93 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 95.2%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 93 min
- Flights arriving 15+ minutes late
- Flights tracked
- 21
- Scheduled flights in the period
What caused the delays
- Airline (crew, maintenance, cleaning) 100%
- Late-arriving aircraft 0%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Dallas (DAL) to Denver (DEN)
Only 18 flights on record, which is too few for reliable odds.
- On-time arrivals
- 44.4%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 74 min
- Flights arriving 15+ minutes late
- Flights tracked
- 18
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 39%
- Air traffic control & airport 30%
- Extreme weather 18%
- Airline (crew, maintenance, cleaning) 13%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
New Orleans (MSY) to Dallas (DAL)
Only 18 flights on record, which is too few for reliable odds.
- On-time arrivals
- 88.9%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 85 min
- Flights arriving 15+ minutes late
- Flights tracked
- 18
- Scheduled flights in the period
What caused the delays
- Air traffic control & airport 100%
- Airline (crew, maintenance, cleaning) 0%
- Late-arriving aircraft 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Nashville (BNA) to Jacksonville (JAX)
Only 16 flights on record, which is too few for reliable odds.
- On-time arrivals
- 56.2%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 39 min
- Flights arriving 15+ minutes late
- Flights tracked
- 16
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 48%
- Airline (crew, maintenance, cleaning) 40%
- Air traffic control & airport 12%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Washington (DCA) to Nashville (BNA)
Only 13 flights on record, which is too few for reliable odds.
- On-time arrivals
- 76.9%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 90 min
- Flights arriving 15+ minutes late
- Flights tracked
- 13
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 75%
- Air traffic control & airport 17%
- Security 5%
- Airline (crew, maintenance, cleaning) 3%
- Extreme weather 0%
Share of delay minutes airlines attributed to each cause (BTS).
Denver (DEN) to Colorado Springs (COS)
Only 9 flights on record, which is too few for reliable odds.
- On-time arrivals
- 55.6%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 34 min
- Flights arriving 15+ minutes late
- Flights tracked
- 9
- Scheduled flights in the period
What caused the delays
- Airline (crew, maintenance, cleaning) 81%
- Late-arriving aircraft 19%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Chicago (MDW) to Long Beach (LGB)
Only 8 flights on record, which is too few for reliable odds.
- On-time arrivals
- 62.5%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 58 min
- Flights arriving 15+ minutes late
- Flights tracked
- 8
- Scheduled flights in the period
What caused the delays
- Airline (crew, maintenance, cleaning) 70%
- Late-arriving aircraft 20%
- Air traffic control & airport 11%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Sacramento (SMF) to Denver (DEN)
Only 8 flights on record, which is too few for reliable odds.
- On-time arrivals
- 75.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 28 min
- Flights arriving 15+ minutes late
- Flights tracked
- 8
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 100%
- Airline (crew, maintenance, cleaning) 0%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Tampa (TPA) to Milwaukee (MKE)
Only 8 flights on record, which is too few for reliable odds.
- On-time arrivals
- 62.5%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 133 min
- Flights arriving 15+ minutes late
- Flights tracked
- 8
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 98%
- Airline (crew, maintenance, cleaning) 2%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Columbus (CMH) to Las Vegas (LAS)
Only 7 flights on record, which is too few for reliable odds.
- On-time arrivals
- 14.3%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 60 min
- Flights arriving 15+ minutes late
- Flights tracked
- 7
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 53%
- Air traffic control & airport 45%
- Airline (crew, maintenance, cleaning) 1%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Dallas (DAL) to Nashville (BNA)
Only 5 flights on record, which is too few for reliable odds.
- On-time arrivals
- 80.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 167 min
- Flights arriving 15+ minutes late
- Flights tracked
- 5
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 100%
- Airline (crew, maintenance, cleaning) 0%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
San Jose (SJC) to Burbank (BUR)
Only 5 flights on record, which is too few for reliable odds.
- On-time arrivals
- 60.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 18 min
- Flights arriving 15+ minutes late
- Flights tracked
- 5
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 53%
- Airline (crew, maintenance, cleaning) 47%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Austin (AUS) to Denver (DEN)
Only 4 flights on record, which is too few for reliable odds.
- On-time arrivals
- 50.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 46 min
- Flights arriving 15+ minutes late
- Flights tracked
- 4
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 45%
- Air traffic control & airport 38%
- Airline (crew, maintenance, cleaning) 16%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Nashville (BNA) to Charlotte (CLT)
Only 4 flights on record, which is too few for reliable odds.
- On-time arrivals
- 25.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 43 min
- Flights arriving 15+ minutes late
- Flights tracked
- 4
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 34%
- Extreme weather 26%
- Airline (crew, maintenance, cleaning) 25%
- Air traffic control & airport 15%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Dallas (DAL) to Las Vegas (LAS)
Only 4 flights on record, which is too few for reliable odds.
- On-time arrivals
- 75.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 84 min
- Flights arriving 15+ minutes late
- Flights tracked
- 4
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 89%
- Airline (crew, maintenance, cleaning) 11%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Dallas (DAL) to San Jose (SJC)
Only 4 flights on record, which is too few for reliable odds.
- On-time arrivals
- 75.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 29 min
- Flights arriving 15+ minutes late
- Flights tracked
- 4
- Scheduled flights in the period
What caused the delays
- Airline (crew, maintenance, cleaning) 73%
- Air traffic control & airport 27%
- Late-arriving aircraft 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Burbank (BUR) to Las Vegas (LAS)
Only 1 flight on record, which is too few for reliable odds.
- On-time arrivals
- 0.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 51 min
- Flights arriving 15+ minutes late
- Flights tracked
- 1
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 100%
- Airline (crew, maintenance, cleaning) 0%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Show as table
| Month | On time | Flights |
|---|---|---|
| September 2025 | 79.3% | 29 |
| October 2025 | 83.9% | 31 |
| November 2025 | 82.8% | 30 |
| December 2025 | 83.9% | 31 |
| January 2026 | 83.3% | 31 |
| February 2026 | 76.9% | 28 |
| March 2026 | 65.8% | 38 |
| April 2026 | 66.7% | 21 |
| May 2026 | 23.5% | 17 |
| June 2026 | 62.2% | 37 |
| July 2026 | 86.5% | 37 |
| August 2026 | 60.6% | 33 |
Source: U.S. DOT Bureau of Transportation Statistics on-time data, September 2025 – August 2026. Covers flights operated by reporting U.S. carriers. About our data