Route profile
IAD→JST
Flight reliability, delays and best times to fly from Washington to Johnstown. · 120 miles
Right now
Current conditions at both ends of this route.
Weather conditions are slightly below ideal. FAA operational data — ground stops, ground delay programs and closures — is not currently available to FlyerIntel.
FlyerIntel does not currently have live operational data for this airport.
Airport conditions describe the airfield, not any individual flight. An airport operating normally is not a guarantee that a specific flight will depart on time.
Route reliability
July 2023 – June 2026
Better than 11% of comparable major US routes (4,577 compared)
Calculated from 1,069 flights. How this is calculated
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – June 2026
Airlines on this route
Performance by the carrier that actually operated the flight.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| SkyWest Airlines | 1,069 | 79.1% | 2.90% | -9 min | 11.5% |
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026 · Carriers with fewer than 200 flights on this route are not listed.
Weekly and seasonal patterns
By day of week
Sunday is historically the most reliable day and Wednesday the least, a gap of 8.0 percentage points.
Historical trend
On-time arrival rate by month.
Over the most recent 12 months (2025-07 to 2026-06), on-time arrivals averaged 75.5% against 79.6% in the 12 months before — declining by 4.1 percentage points.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026
Data and methodology
All figures on this page are calculated by FlyerIntel from 1,069 IAD → JST flight records published by the US DOT Bureau of Transportation Statistics, covering July 2023 – June 2026. A flight is counted as delayed when it arrives 15 or more minutes after its scheduled arrival time, following BTS methodology. Cancelled and diverted flights have no arrival time and are excluded from on-time rates rather than counted as late.