From the blog

#schedules

3 articles tagged #schedules.

A single departure time interpreted three ways — local, UTC, and across a DST boundary — diverging into different answers, in Active Flights brand cyan on near-black.
SSIM & Schedules·

Time zones, UTC and DST: the schedule's quiet minefield

Almost every serious schedule-data bug is, at bottom, a time bug. Local vs UTC, per-station offsets, and daylight-saving transitions turn a simple 'departure time' into one of the trickiest fields in the file.

#ssim#time-zones#utc#dst
A single schedule rule expanding into a calendar of concrete operating dates, with day-of-week markers, in Active Flights brand blue on near-black.
SSIM & Schedules·

Days of operation and period expansion: the date math that breaks parsers

A single SSIM flight-leg line isn't one flight — it's a rule that expands into many. Getting that expansion exactly right, across days-of-operation, frequency, and season edges, is where a lot of quiet bugs live.

#ssim#schedules#dates#day-of-operation
One flight represented by a marketing carrier code and a separate operating carrier code, showing the split between who sells and who flies, in Active Flights brand cyan on near-black.
SSIM & Schedules·

Codeshares, wet leases, and operating carriers: reading who really flies

The flight number you book isn't always the airline that flies you. Here's the difference between marketing and operating carriers, codeshares, and wet/dry leases — and how it all shows up in the schedule.

#codeshare#wet-lease#operating-carrier#schedules