This action proposes to establish Area Navigation RNAV routes Q-162 and Q-166 in the Southwest United States. The proposed new RNAV routes would provide alternative routing for air traffic travelling between southwest Arizona and western Texas in response to severe weather events during the spring and summer months. Additionally the new RNAV routes would expand the availability of RNAV routing in support of transitioning the National Airspace System NAS from a ground-based to satellite-based system for navigation.