Complex sentence: The only big jets at Grand Junction now are Allegiant Air McDonnell Douglas MD-80s several days a week nonstop to Las Vegas and Los Angeles; other airlines use regional jets to various hubs.
Split into simpler sentences: The only big jets at Grand Junction now are Allegiant Air McDonnell Douglas MD-80s several days a week nonstop to Las Vegas and Los Angeles. The other airlines use regional jets to various hubs.