bulldog10 wrote:
The weight of fuel on board a plane for a long flight can be a significant factor. The weight of the extra fuel causes you to burn more fuel per mile. Most commercial jets can certainly fly Toronto to San Jose non-stop. But if you stop for a refuel you are flying with less full tanks. Overall saving some fuel. At current fuel prices might be worthwhile.
In this case it is not that I think, because an extra landing and takeoff an hour from the destination would use far more fuel. San Salvador is a hub for Avianca, and this flight has always stopped in San Salvador. You can then connect through San Salvador to many points in South and Central America.
For some reason they also have always called this a "direct flight" to San Jose, but not a "non-stop" flight. Maybe because it is operated by the Costa Rican subsidiary of Avianca, or just for marketing purposes.