Minimum Connecting Time (MCT) Comparison Guide
Overview
Minimum Connecting Time (MCT) rules define the valid connection intervals required between arriving and departing flights at an airport. When carriers or airport authorities adjust these rules between schedule releases, connection validity, booking eligibility, and passenger itineraries are directly impacted.
This guide details how to perform an automated MCT delta comparison across published schedule iterations, broken down into three focused audit reports.
The Three Audit Reports
To prevent critical connection adjustments from being obscured in a monolithic list, MCT changes are separated into three distinct operational categories:
1. Standard & Terminal Level Changes
Captures base airport defaults and terminal-to-terminal transfers.
- Scope: Airport default D-D, D-I, I-D, and I-I connection times, as well as terminal-pair defaults.
- Primary Impact: Global connection feasibility for all non-exempt carriers operating at the station.
2. Online & Carrier-Specific Exceptions
Captures single-carrier specific rule modifications.
- Scope: Tailored carrier rules, specific terminal routings, equipment-type exceptions, and flight number range variations (e.g., specific long-haul banks).
- Primary Impact: Operating efficiency, hub bank connectivity, and minimum transfer thresholds for specific airlines.
3. Interline & Partner Exceptions
Captures carrier-to-carrier transfer adjustments.
- Scope: Bilateral partner agreements, codeshare feed arrangements, alliance transfers, and inter-terminal baggage/passenger transfers between different airlines.
- Primary Impact: Multi-airline itineraries, alliance hub feeds, and codeshare booking availability.
Report Output Schema & Field Definitions
Each comparison report presents changes in a side-by-side format using the following structure:
| Field | Description | Example |
|---|---|---|
| Rule Type | Connection category (D-D, D-I, I-D, I-I, Terminal, Flight Range) | I-D |
| Inbound Details | Inbound Carrier, Arriving Terminal, or Flight Range | BA (T5, Flt 0001-0299) |
| Outbound Details | Outbound Carrier, Departing Terminal, or Flight Range | AA (T3, Flt 0100-0500) |
| Previous MCT | Required time (in minutes) in the prior schedule release | 90 min |
| Current MCT | Required time (in minutes) in the active schedule release | 75 min |
| Variance / Change Type | Net difference and action (Added, Deleted, +15 min, -15 min) | -15 min (Modified) |
Change Classification Reference
- Added: A new exception or rule created in the current release that did not exist previously.
- Deleted: A rule or exception that was active in the previous release and has now been removed (reverting traffic to base airport or alliance defaults).
- Modified (Increased): Connecting time increased (e.g., 60 min → 75 min), potentially invalidating tight itineraries.
- Modified (Decreased): Connecting time reduced (e.g., 90 min → 70 min), opening new sellable connection pairs.