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Tagged · SSIM

7 articles on SSIM.

Aircraft type codes shown in both IATA three-character and ICAO four-character forms mapping to the same aircraft, in Active Flights brand amber on near-black.
·SSIM

Reading aircraft type codes: IATA vs ICAO in the schedule

The 'equipment' field in a schedule is a short code for an aircraft type — and there are two competing code systems for it. Knowing which is which, and mapping between them, is a small skill that prevents big mistakes.

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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

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.

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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

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.

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A validation panel listing schedule issues, some flagged as real errors and some acknowledged as known conventions, in Active Flights brand amber on near-black.
·SSIM

The data-quality edge cases that break schedule parsers

A field guide to the real-world quirks in SSIM feeds — time modes, overnight arrivals, DST, operational suffixes, season edges — that turn a 'simple' fixed-width parser into a maintenance treadmill.

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Schedule-change action-code chips — NEW, CNL, TIM, EQT — flowing from a schedule to downstream systems, in Active Flights brand blue on near-black.
·SSIM

SSM and ASM: how schedule changes actually travel

A schedule is published once, then changed constantly. SSM and ASM are the IATA messages that carry those changes — bulk and ad-hoc — with action codes like NEW, CNL, TIM and EQT. Here's how they work.

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A stack of five labelled SSIM record-type rows — a header, a carrier record, a flight leg, a segment record, and a trailer — in Active Flights brand blue on near-black.
·SSIM

SSIM Chapter 7 record types, explained: reading a schedule file end to end

A field-level walk through the SSIM record types — header, carrier, flight leg, segment data, and trailer — with a sample file, the fields that matter, and the gotchas that bite parsers.

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A raw fixed-width SSIM record line decoding into labelled structured fields, in Active Flights brand cyan on near-black.
·SSIM

What is IATA SSIM? A plain-English guide to the format that runs airline schedules

SSIM is how the airline industry exchanges its schedules — a fixed-width, 200-byte text format that's deceptively simple and genuinely hard to get right. Here's what it is and why it matters.

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