It seems the only options available for passengers these days are large airports such as Portland, Seattle, San Francisco or Los Angeles. Can you tell me why the airlines no longer offer short-hop trips to places like Eugene, North Bend, Klamath Falls, Redding or Chico — all places I seem to remember flying to while en route to Portland, Sacramento or San Francisco?

It seems the only options available for passengers these days are large airports such as Portland, Seattle, San Francisco or Los Angeles. Can you tell me why the airlines no longer offer short-hop trips to places like Eugene, North Bend, Klamath Falls, Redding or Chico — all places I seem to remember flying to while en route to Portland, Sacramento or San Francisco?

— Dorris B., Medford

Those destinations reflect a time when airlines viewed their routes much differently than today.

The milk-run routes were common in an era when airline schedules looked something like those of Greyhound and Trailways bus lines.

There are two distinct reasons why the milk runs that were still around into the 1980s in some parts of the country went away.

One is readily understandable in this era of high fuel prices. Getting airborne and climbing to altitude requires a substantial amount of an aircraft's fuel capacity, depending on the type of plane.

"Every landing and takeoff adds up," said Bern Case, the Medford airport director. "You can cover a lot of miles for the same amount of fuel that it took to get into the air."

A second aspect of the present hub and spoke model is that a passenger has geometrically more options.

"If you fed nine cities into the hub airport, connecting with three round-trips a day, that's 81 opportunities per hub city," Case said. "You can get a tremendous amount of activity with nine aircraft, and that's how hubbing began."

Southwest, one airline that doesn't subscribe to the hub-and-spoke routine, doesn't fly as many short routes as you remember.

"Southwest goes to large airports with a tremendous amount of flights," Case said. "You can go across the U.S. and stop in six cities. But it's the exception these days."

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