The age of the airship is back, kind of. On 15 May, startup LTA Research flew its Pathfinder 1 airship outside Silicon Valley’s Moffett Federal Airfield for the first time. The 124-meter-long helium airship took two loops over the waters of San Francisco Bay before safely returning to base. That makes it the largest aircraft to fly in public since the 1930s, when a series of crashes ended the glory years of airship travel. (LTA has flown smaller, traditional blimps in the Bay Area a number of ti...