The reason the ARJ/146 are the only "real" jets that can make it in and out of Aspen is they are the only planes that can turn fast enough without hitting AJAX or any other mountain if they have to do a go around.

When flying into the valley, take notice of a "HUGE" dip about 1,000 feet above the ground on short final into Pitkin Field... that's because of the winds... the 146 can handle it gracefully whereas an airframe like the CRJ or ERJ would have one heck of a time getting in... plus they would have to come in at normal landing speed + 30 kts to maintain the change in winds over the ridge.

The footprint (landing gear size) has a lot to do w/ the aircraft as well.. take notice that you NEVER have a rough landing on an Avro ARJ85 or BAe 146....

-n