It's been seven years since Alison Krauss & Union Station last recorded together, an interim marked by myriad outside projects, none more noteworthy than Krauss' Grammy Award-gobbling "Raising Sand" collaboration with Robert Plant. If that success kindled additional interest for Union Station, the new arrivals won't be disappointed, and longtime fans of the rootsy quintet will feel rewarded for their patience. Austere and melancholy, dealing mostly with heartbreaks and farewells with a modicum of hope, new album "Paper Airplane" still conveys the rich and understated beauty that's always been the group's trademark. Krauss, whose fiddle is a minor presence this time out, sings with a greater authority on versions of Jackson Browne's "My Opening Farewell" and Richard Thompson's "Dimming of the Day," while Robert Lee Castleman's title track and first single is a three-hanky special. Fortunately there's still guitarist Dan Tyminski, who's there for the upswing of tracks like "Dust Bowl Children," "On the Outside Looking In" and "Bonita and Bill Butler."