Schedule Change Impact for Lost & Added Connections
This guide walks you through executing and interpreting a Schedule Connectivity Comparison between two schedule baselines (or SSIM versions) for a target carrier and hub.
PROMPT1. Parameter Reference
| Parameter | Required | Example Values | Description |
|---|---|---|---|
| Carrier Code | Yes | KM, BA, LH | The 2-letter IATA (or 3-letter ICAO) code of the validating/marketing carrier. |
| Latest Schedule | Yes | 2025-06-01, SSIM_W24_v3 | The target/new schedule release or SSIM version to evaluate. |
| Previous Schedule | Yes | 2025-05-01, SSIM_W24_v2 | The baseline schedule used for variance comparison. |
| Hub / Gateway | Yes | MLA, FRA, LHR | Hub station code where inbound and outbound legs connect. |
| Scope / O&D Pairs | Optional | ALL, MLA-LHR, FCO-MLA-LGW | Specific city pairs or all network pairs routed via the hub. |
| MCT (Minimum) | Optional | Default or 45 min | Minimum connection time enforced at the hub (station default or custom). |
| Max Connect Time | Optional | 300 min (5 hours), 360 min | Upper bound for acceptable connection elapsed time. |
| Connection Types | Optional | Online only, Online + Interline | Include only own-metal flights or partner/codeshare combinations. |
2. Analysis Methodology & Workflow
flowchart LR
A[Baseline Schedule] --> C[Connection Builder Engine]
B[Latest Schedule] --> C
C --> D{MCT & Max Window Filter}
D --> E[Identify Gained Pairs]
D --> F[Identify Lost / Missed Pairs]
D --> G[Calculate Frequency & Elapsed Time Variance]
E --> H[Consolidated O&D Summary Report]
F --> H
G --> H
Key Metrics Defined
- Gained Connections: City-pair combinations that are valid under the latest schedule but did not exist or meet connection criteria in the baseline.
- Missed / Lost Connections: Pairs that were valid in the baseline schedule but are broken in the latest schedule due to:
- Flight cancellation / de-scheduling.
- Retimed arrival/departure violating Hub MCT.
- Retimed flight exceeding the Maximum Connect Time window.
- Net Frequency Variance (Δ Freq): Difference in weekly connecting frequencies per directional O&D.
- Average Elapsed Time (Δ Elapsed): Change in total journey time (Inbound Block Time + Layover + Outbound Block Time).
3. Expected Output Schema
When the comparison is complete, results are provided in the following structured layout:
A. Network Executive Summary
- Hub: MLA
- Analyzed Period: SSIM v2 (Baseline) vs SSIM v3 (Current)
- Total O&D Markets Evaluated: 142
- Net Weekly Connecting Frequencies: +18 (+4.2%)
- Total Gained Connection Pairs: 34
- Total Lost Connection Pairs: 16
- Average System Elapsed Time Change: -12 mins (improved)
B. Market Breakdown (O&D Level)
| Market (O&D) | Baseline Wkly Freq | Current Wkly Freq | Net Change (Δ) | Gained Pairs | Lost Pairs | Avg Elapsed Time (Δ) | Primary Driver / Notes |
|---|---|---|---|---|---|---|---|
| FCO – MLA – VIE | 7 | 10 | +3 | 3 | 0 | -15 min | Added afternoon FCO bank |
| LHR – MLA – CTA | 14 | 7 | -7 | 0 | 7 | +45 min | KM retimed LHR arrival past MCT |
| MUC – MLA – TIP | 0 | 5 | +5 | 5 | 0 | 210 min | New seasonal connecting service |
4. Troubleshooting & Common Pitfalls
Check Time Zones & Date Overlaps Ensure both baseline and comparison datasets cover identical day-of-week matrices or equivalent effective date ranges to avoid false "lost" connection signals caused by seasonal date boundaries.
Terminal-Specific MCTs If your hub operates multiple terminals, ensure terminal transfer times are accounted for if standard station-level MCT is not uniform across all gates.
5. Next Steps & Follow-Up Prompts
Once you receive the connectivity results, you can branch into detailed operational reviews:
Export Data: "Export the full connection variance table to a CSV file for Excel analysis." Visualise Impact: "Generate a bar chart comparing the top 10 gained vs top 10 lost markets by weekly frequency." Schedule Diagnostics: "Show the exact flight arrival and departure times for the lost connections on the LHR–MLA–CTA route."