Ideally, the best way to address this would be to implement NDC (New Distribution Capability) for Singapore Airlines. But what if NDC isn't available?

To answer this, let’s take a moment to understand how the flight search API works within a GDS (Global Distribution System). GDS uses a powerful Lowest Available Fare (LAF) mechanism to retrieve results that aim to strike a balance across the various fare brands or families offered by airlines. However, each API call returns a maximum of 200 results. Since Singapore Airlines typically offers higher fares, its flights may fall outside this range and therefore get excluded from the final results.

To tackle this, we can implement rules based on "human intelligence" for common routes and their expected airlines—particularly when it involves a national carrier.

These rules guide the OBT to perform an additional search specifically using the chosen airline, effectively “forcing” its results to appear.

Implementing an online booking engine or corporate booking tool goes beyond simply subscribing to or developing a product—it also requires expert consultation from professionals with deep technical and industry knowledge.