ANCHORAGE, Alaska (AP) — An air carrier based in Alaska says it's filing a Chapter 11 reorganization plan.

PenAir announced Monday it's closing its Denver hub pending approval from the U.S. Department of Transportation.

The move would end essential air service routes between Denver and Liberal and Dodge City in Kansas, and the Nebraska cities of North Platte, Kearney (CARN'-ee) and Scottsbluff.

The company says a transition to a new carrier usually takes 30 to 90 days.

PenAir had previously announced it was ending Portland, Oregon, regional routes. All but an essential air service route between Portland and Crescent City, California, are to be shut down after Monday.

Operations in Alaska and Boston will not be affected.

PenAir CEO Danny Seybert in the announcement says the reorganization will allow the company to emerge as a stronger airline.