Flight WN4438
Southwest Airlines flight WN4438
Looking for WN4438 in the air…
St Louis (STL) to Chicago (MDW)
Historically, this flight arrives 15+ minutes late 17% of the time, and when it is late the delay averages 48 minutes. It was cancelled 3.6% of the time.
- On-time arrivals
- 83.0%
- Less than 15 minutes late
- Cancelled
- 3.6%
- Of scheduled flights
- Average delay when late
- 48 min
- Flights arriving 15+ minutes late
- Flights tracked
- 55
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 51%
- Airline (crew, maintenance, cleaning) 25%
- Air traffic control & airport 24%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Baltimore (BWI) to Jacksonville (JAX)
Historically, this flight arrives 15+ minutes late 39% of the time, and when it is late the delay averages 56 minutes. It was cancelled 9.3% of the time.
- On-time arrivals
- 60.5%
- Less than 15 minutes late
- Cancelled
- 9.3%
- Of scheduled flights
- Average delay when late
- 56 min
- Flights arriving 15+ minutes late
- Flights tracked
- 43
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 73%
- Air traffic control & airport 12%
- Extreme weather 10%
- Airline (crew, maintenance, cleaning) 6%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
St Louis (STL) to Boston (BOS)
Historically, this flight arrives 15+ minutes late 41% of the time, and when it is late the delay averages 47 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 59.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 47 min
- Flights arriving 15+ minutes late
- Flights tracked
- 39
- Scheduled flights in the period
What caused the delays
- Air traffic control & airport 49%
- Late-arriving aircraft 28%
- Airline (crew, maintenance, cleaning) 21%
- Extreme weather 2%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
San Jose (SJC) to Baltimore (BWI)
Historically, this flight arrives 15+ minutes late 34% of the time, and when it is late the delay averages 31 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 65.6%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 31 min
- Flights arriving 15+ minutes late
- Flights tracked
- 32
- Scheduled flights in the period
What caused the delays
- Airline (crew, maintenance, cleaning) 46%
- Late-arriving aircraft 36%
- Air traffic control & airport 19%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Nashville (BNA) 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
- 50 min
- Flights arriving 15+ minutes late
- Flights tracked
- 4
- 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).
Phoenix (PHX) to Louisville (SDF)
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
- 32 min
- Flights arriving 15+ minutes late
- Flights tracked
- 1
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 69%
- Airline (crew, maintenance, cleaning) 31%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Portland (PWM) to Baltimore (BWI)
Only 1 flight on record, which is too few for reliable odds.
- On-time arrivals
- 100.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- —
- Flights arriving 15+ minutes late
- Flights tracked
- 1
- Scheduled flights in the period
Louisville (SDF) to Phoenix (PHX)
Only 1 flight on record, which is too few for reliable odds.
- On-time arrivals
- 100.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- —
- Flights arriving 15+ minutes late
- Flights tracked
- 1
- Scheduled flights in the period
Sacramento (SMF) to Las Vegas (LAS)
Only 1 flight on record, which is too few for reliable odds.
- On-time arrivals
- 100.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- —
- Flights arriving 15+ minutes late
- Flights tracked
- 1
- Scheduled flights in the period
Show as table
| Month | On time | Flights |
|---|---|---|
| October 2025 | 100.0% | 1 |
| November 2025 | 92.0% | 26 |
| December 2025 | 72.0% | 26 |
| January 2026 | 100.0% | 4 |
| February 2026 | 100.0% | 1 |
| March 2026 | 73.1% | 26 |
| April 2026 | 45.5% | 22 |
| May 2026 | 60.9% | 23 |
| June 2026 | 57.9% | 20 |
| July 2026 | 63.2% | 23 |
| August 2026 | 80.0% | 5 |
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