I think the two biggest problems for regionals here in Europe are the higher population density and the well-developed alternative links.
Higher population density:
Population centers are located relatively close together, and there are comparatively few "gaps" that need to be bridged. Therefore, you're always vaguely "near" a larger population center, and an airport the big carriers serve. There are very few airports/areas in Europe that really are far enough away from everything else to support a regional carrier.
InterSky is a good example of this: Friedrichshafen is at least 2 hours from any of the nearest major airports (ZRH
), rail links are slow by European standards, and road links are also somewhat limited. This is mostly due to geography, the presence of Lake Constance and the mountainous terrain isolate the area a bit. Despite this, the region is affluent and also generates inbound traffic. This allowed InterSky to build a nice little niche operation there.
Well-developed alternative links:
I'm mostly thinking rail here, more specifically high-speed rail, but also motorway networks. It is often said that the critical threshold beyond which people will choose to fly is a 4-hour trip by train. With high-speed rail, that four hour window covers a lot of distance. From Frankfurt, for example, you can be in Paris, Zurich, Munich, Amsterdam, Hamburg or Berlin in four hours (or slightly more) if you take the train. Lateral links between smaller population centers are also good. This makes it tough to build a business case for regional air services on a lot of routes (unless they're feeders to hubs).
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