Washington to Johnstown

What the Data Says About IAD to JST

The Washington to Johnstown corridor (IAD → JST) covers roughly 120 miles and is served by 1 carrier, based on Bureau of Transportation Statistics reporting. Across 1,559 flights in the dataset, this route posts a 83.4% on-time rate with an average delay of 133.8 minutes when flights run late. Over the most recent 24 months of BTS data, 735 flights were recorded on this pairing — 14 cancelled (1.9%) and 8 diverted (1.1%). Those baseline metrics tell you what to expect before you book.

Having 1 carrier on the route matters: more carriers generally means more daily schedule options, competitive pricing, and redundancy when flights are cancelled. With 1,559 total flights analyzed, the 83.4% on-time figure is statistically meaningful rather than a small-sample fluke. The 133.8-minute average delay applies only to flights that actually ran late, so it is not the average wait across all departures — the majority of flights on this route depart on time under the BTS definition of a delay (15+ minutes past schedule).

Monthly performance varies, so review the monthly table above to see specific periods. For travelers evaluating the IAD to JST route, the combination of a 83.4% on-time rate, 133.8-minute average delay, 1.9% recent cancellation rate, and 1 available carrier is the concrete summary of what BTS data shows about reliability on this pairing.