Rest in peace, sweet pup.

After a brave battle with prostate cancer, 9-year-old border collie Piper has been euthanized.

Piper gained notoriety in 2016, when his story went viral - he was the official runway dog for the Cherry Capital Airport. His job was to herded away geese, ducks, birds...and even snowy owls off the runway.

He spent his final hours with his loving family and was presented with an American flag from the Coast Guard station in Traverse City.