Cape Air (KAP) on-time performance, September 2026
4,437 scheduled Cape Air departures in US airspace in September 2026, 69.4% of them on time. Measured from FAA departure data, updated every morning.
On time, day by day
Share of Cape Air departures within 15 minutes of schedule, by day. Light bars show each day's departures for context. Worst day: Friday 4 September at 51.1%. Best: Saturday 26 September at 93.3%.
Airports, ranked by on-time share
Airports with at least 30 Cape Air departures in the month.
| Airport | Departures | On time | 45+ min late | Avg delay (min) |
|---|---|---|---|---|
| HVR Havre | 55 | 92.7% | 1.8% | -3.1 |
| JFK New York | 53 | 86.8% | 5.7% | -6.4 |
| STT St. Thomas | 120 | 86.7% | 4.2% | 1.5 |
| SJU San Juan | 127 | 85.8% | 7.9% | 6.2 |
| HPN White Plains | 58 | 84.5% | 6.9% | 3.3 |
| BIL Billings | 347 | 83.3% | 11.2% | 24.5 |
| STX St. Criox Island | 59 | 74.6% | 8.5% | 14.3 |
| MVY Martha'S Vineyard | 338 | 70.7% | 18.0% | 17.9 |
| HYA Hyannis | 318 | 69.8% | 18.9% | 19.2 |
| LEB Lebanon | 139 | 67.6% | 11.5% | 13.9 |
| ACK Nantucket | 512 | 64.8% | 20.9% | 21.1 |
| RKD Rockland | 116 | 64.7% | 18.1% | 23.0 |
| AXA The Valley | 31 | 64.5% | 6.5% | 11.6 |
| BHB Bar Harbor | 196 | 64.3% | 16.3% | 17.5 |
| ISP Islip | 84 | 64.3% | 19.0% | 17.0 |
| AUG Augusta | 103 | 64.1% | 20.4% | 20.0 |
| SLK Saranac Lake | 78 | 64.1% | 25.6% | 22.4 |
| PVC Provincetown | 160 | 63.8% | 19.4% | 21.6 |
| RUT Rutland | 82 | 59.8% | 20.7% | 30.4 |
| BOS Boston | 1,081 | 58.2% | 26.0% | 51.4 |
Least punctual routes
Routes with at least 20 Cape Air departures, lowest on-time share first.
| Route | Flights | On time | Avg delay |
|---|---|---|---|
| SLK to BOS Saranac Lake to Boston | 49 | 44.9% | 41.0 |
| BOS to ACK Boston to Nantucket | 281 | 49.1% | 67.5 |
| BOS to PVC Boston to Provincetown | 76 | 53.9% | 81.8 |
| HYA to BOS Hyannis to Boston | 136 | 55.1% | 38.1 |
| ACK to BOS Nantucket to Boston | 346 | 56.1% | 28.8 |
| BOS to HYA Boston to Hyannis | 103 | 56.3% | 39.0 |
| LEB to BOS Lebanon to Boston | 97 | 56.7% | 22.0 |
| BOS to LEB Boston to Lebanon | 58 | 58.6% | 35.0 |
| RUT to BOS Rutland to Boston | 78 | 60.3% | 27.4 |
| BOS to ISP Boston to Islip | 56 | 60.7% | 55.1 |
Busiest routes
The ten routes Cape Air flew most this month.
| Route | Flights | On time | Avg delay |
|---|---|---|---|
| ACK to BOS Nantucket to Boston | 346 | 56.1% | 28.8 |
| BOS to ACK Boston to Nantucket | 281 | 49.1% | 67.5 |
| MVY to BOS Martha'S Vineyard to Boston | 228 | 65.4% | 26.8 |
| BHB to BOS Bar Harbor to Boston | 190 | 64.2% | 17.9 |
| BOS to MVY Boston to Martha'S Vineyard | 166 | 62.0% | 51.8 |
| PVC to BOS Provincetown to Boston | 157 | 63.1% | 22.3 |
| HYA to BOS Hyannis to Boston | 136 | 55.1% | 38.1 |
| HYA to ACK Hyannis to Nantucket | 119 | 85.7% | 0.1 |
| BIL to KSDY Billings to | 119 | 85.7% | 14.3 |
| KSDY to BIL to Billings | 116 | 88.8% | 3.1 |
Other months for Cape Air
Airport pages for September 2026
How we measure
On time means the aircraft took off within 15 minutes of its scheduled departure, after subtracting the departure airport's normal taxi time (FAA SWIM reports wheels-off, not push-back, so the median taxi time of the last 30 days is taken off every flight first). Average delay is the mean of that taxi-adjusted delay over all departures; early departures count as negative minutes, so an operator that routinely leaves early can show a negative average. 45+ min late is the share of departures that left 45 minutes or more behind schedule, the point at which most connections are at risk.
Scope: scheduled airlines only, the same set as the monthly State of the Sky report (operators with published routes; private, fractional and charter operators are left out), so the two publications give the same numbers for the same month. Departures are counted by scheduled day (UTC). Each day's flights are rolled up overnight and published the next morning; the newest day keeps filling in for a day or two and is only shown once it is substantially complete. Figures can differ by a few tenths of a point from the State of the Sky report for the same month: that report is frozen on the 2nd of the following month, while these pages are rebuilt from the live rollup, which recomputes each airport's taxi baseline nightly and re-rolls the last week of the month as late departure times arrive (September 2026 at SFO: 16,398 departures in both, 69.2% on time here against 69.5% in the report).
Source: FAA System Wide Information Management (SWIM) flight plans and departure times, processed by PlaneTrack. Free to quote with credit to PlaneTrack (CC BY 4.0).