Best Time to Fly ORD to MDT: On-Time Stats by Hour & Airline
Chicago O'Hare International → Harrisburg International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 73.6% of Chicago (ORD) to Harrisburg (MDT) flights arrived on time (2,131 scheduled flights). That is 4.1 points below the national average of 77.6%.
Among 5 airlines, Republic Airways led with 80.4% on time and American Airlines was last with 66.9%.
Over 24 months, Saturday was the most reliable day (78% on time) and December the worst month (67%).
The cancellation rate was 3.3% (US average 1.8%).
ORD to MDT on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| Republic Airways | 80.4% | 64 min | 3.7% | 355 |
| Envoy Air | 78.2% | 62 min | 2.7% | 625 |
| United Airlines | 69.7% | 70 min | 2.8% | 602 |
| SkyWest Airlines | 68.9% | 76 min | 3.9% | 285 |
| American Airlines | 66.9% | 100 min | 4.5% | 264 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly ORD to MDT
On-time arrival % by scheduled departure hour (local time), 3,242 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 7am–8am | 73.0% | 1.0% | 312 |
| 8am–9am | 84.7% | 0.6% | 336 |
| 9am–10am | 79.4% | 4.5% | 67 |
| 10am–11am | 75.0% | 4.8% | 42 |
| 11am–12pm | 64.7% | 3.8% | 53 |
| 12pm–1pm | 71.9% | 0.0% | 32 |
| 1pm–2pm | 80.4% | 2.1% | 725 |
| 2pm–3pm | 72.3% | 3.7% | 135 |
| 3pm–4pm | 72.0% | 1.3% | 228 |
| 4pm–5pm | 69.2% | 4.4% | 136 |
| 5pm–6pm | Limited data | 20 | |
| 6pm–7pm | 66.8% | 1.6% | 579 |
| 7pm–8pm | 61.5% | 3.7% | 162 |
| 8pm–9pm | 69.2% | 5.2% | 288 |
| 9pm–10pm | 74.2% | 5.5% | 127 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on ORD to MDT
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 55.8% | -19.7 pts | 13.3% | 60 |
| Christmas & New Year (Dec 20 - Jan 3) | 67.9% | -7.6 pts | 2.3% | 86 |
| Summer peak (Jun 15 - Aug 15) | 69.1% | -6.3 pts | 2.3% | 598 |
| All other days | 75.5% | — | 2.2% | 2,498 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).