Flight YX4521
Republic Airways flight YX4521
Looking for YX4521 in the air…
New York (LGA) to Buffalo (BUF)
Historically, this flight arrives 15+ minutes late 33% of the time, and when it is late the delay averages 96 minutes. It was cancelled 13.3% of the time.
- On-time arrivals
- 66.7%
- Less than 15 minutes late
- Cancelled
- 13.3%
- Of scheduled flights
- Average delay when late
- 96 min
- Flights arriving 15+ minutes late
- Flights tracked
- 90
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 54%
- Air traffic control & airport 30%
- Airline (crew, maintenance, cleaning) 12%
- Extreme weather 4%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Hartford (BDL) to Chicago (ORD)
Historically, this flight arrives 15+ minutes late 31% of the time, and when it is late the delay averages 56 minutes. It was cancelled 9.5% of the time.
- On-time arrivals
- 69.3%
- Less than 15 minutes late
- Cancelled
- 9.5%
- Of scheduled flights
- Average delay when late
- 56 min
- Flights arriving 15+ minutes late
- Flights tracked
- 84
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 65%
- Air traffic control & airport 30%
- Airline (crew, maintenance, cleaning) 4%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Chicago (ORD) to Hartford (BDL)
Historically, this flight arrives 15+ minutes late 25% of the time, and when it is late the delay averages 90 minutes. It was cancelled 6.1% of the time.
- On-time arrivals
- 75.3%
- Less than 15 minutes late
- Cancelled
- 6.1%
- Of scheduled flights
- Average delay when late
- 90 min
- Flights arriving 15+ minutes late
- Flights tracked
- 82
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 43%
- Air traffic control & airport 22%
- Airline (crew, maintenance, cleaning) 18%
- Extreme weather 17%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
New York (LGA) to St Louis (STL)
Historically, this flight arrives 15+ minutes late 9% of the time, and when it is late the delay averages 107 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 90.9%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 107 min
- Flights arriving 15+ minutes late
- Flights tracked
- 33
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 65%
- Airline (crew, maintenance, cleaning) 31%
- Air traffic control & airport 5%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
St Louis (STL) to New York (LGA)
Historically, this flight arrives 15+ minutes late 16% of the time, and when it is late the delay averages 74 minutes. It was cancelled 3.0% of the time.
- On-time arrivals
- 84.4%
- Less than 15 minutes late
- Cancelled
- 3.0%
- Of scheduled flights
- Average delay when late
- 74 min
- Flights arriving 15+ minutes late
- Flights tracked
- 33
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 78%
- Air traffic control & airport 12%
- Airline (crew, maintenance, cleaning) 11%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Pittsburgh (PIT) to Chicago (ORD)
Historically, this flight arrives 15+ minutes late 17% of the time, and when it is late the delay averages 72 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 83.3%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 72 min
- Flights arriving 15+ minutes late
- Flights tracked
- 30
- Scheduled flights in the period
What caused the delays
- Extreme weather 66%
- Airline (crew, maintenance, cleaning) 18%
- Air traffic control & airport 16%
- Late-arriving aircraft 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Nashville (BNA) to Chicago (ORD)
Only 13 flights on record, which is too few for reliable odds.
- On-time arrivals
- 53.8%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 72 min
- Flights arriving 15+ minutes late
- Flights tracked
- 13
- Scheduled flights in the period
What caused the delays
- Airline (crew, maintenance, cleaning) 81%
- Air traffic control & airport 19%
- Late-arriving aircraft 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Chicago (ORD) to Cincinnati / Covington (CVG)
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 |
|---|---|---|
| September 2025 | 85.2% | 27 |
| October 2025 | 80.0% | 5 |
| November 2025 | 100.0% | 3 |
| December 2025 | 76.3% | 38 |
| January 2026 | 76.5% | 56 |
| February 2026 | 65.2% | 23 |
| March 2026 | 69.0% | 48 |
| April 2026 | 73.8% | 44 |
| May 2026 | 88.1% | 43 |
| June 2026 | 66.7% | 26 |
| July 2026 | 65.2% | 27 |
| August 2026 | 60.0% | 26 |
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