WN→AUS

Spirit Airlines cancels 6.5% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.

The 8pm–5am window is where this operation falls apart: 59.3% on time, against 95.1% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 2pm–5pm window is the busiest, with 8,482 flights scheduled in it.

June is the worst month at 59.8% on time, 25 points below January, the best at 85.1%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. July was the busiest month here, with 3,545 flights.

54% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 530,000 reported delay minutes here, that single category outweighs weather by 39 to one. The split is drawn from 529,600 reported delay minutes.

Cancellations are rare at 0.61%, below the national 1.89% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.

7.1% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about 50 minutes, which a normal layover absorbs.

38,550 flights sit behind these numbers, which is a large enough sample that the headline rate is not moving on noise. Where a sub-group falls below 30 flights the site shows a dash instead of a percentage.

Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 85.1% on time and June 59.8%, a swing of 25 points. If the dates move at all, move them out of June before you think about anything else. 38,238 completed flights over 12 months sit behind that.