AUGUSTA – Sens. Angus King and Susan Collins of Maine are urging federal officials to make it possible for National Park passes to be purchased online or through a phone app.

In a letter to the U.S. Department of the Interior and the National Park Service on Tuesday, King and Collins suggest that a pilot program could be set up at Maine’s Acadia National Park on Mount Desert Island to test the electronic sale of passes.

The senators say visitors could be emailed passes that would then be scanned at the park, like airline tickets. They say doing so would make it easier for people to buy tickets and greatly increase revenue for national parks.

They say it’s time to move the park system “into this new century.”