To answer the original question:
It would depend on route structure, as stated above. If we're talking about n/s flights JFK
, then the A318 would definetely be your choice (if you wanted to go that small). More likely, the A318 would be suited for JFK
If you're talking about short hops like PHF-ATL
, then you're more inclined to go with the 717. If you have several of them, you could even fly LGA
(You'll notice I'm using examples of real airlines, though some of the routes are made-up)
The operational characteristics of the A318 are a long-range, low-density route system similar to JetBlue's cross-country routes, with a modicum of frequency.
The characterisitcs of the 717 are for short-medium hops directly varying density and frequency (more density=more flights, less density=fewer flights).
The idea is, the 717 is a single-type scalable frequency aircraft, while the A318 is a scalable type (A318/19/20) limited frequency aircraft. Each has its own merits.
The real question is not what kind of aircraft you're going to fly as a low-cost/low fare carrier, but rather what kind of LCC are you going to be?
Of course, if you based your system at MCI
, or other mid-US airport, it'd be pretty tough to choose. That's when Boeing/Airbus really go head-to-head in the 100-seat market.
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