Show lighter V than air ships there are three general types of lighter than air ships the rigid the semi rigid and non rigid some airship authorities divide them into only two types the pressure airship and the rigid airship the pressure ship which includes both the non rigid and the semi rigid maintains its shape and withstands the stresses stress ds and strains of flight because of the internal pressure of the lifting gas the rigid is shaped by its internal structure over which the fabric is stretched like a skin the huge german airship hindenburg which burned at lakehurst in 1937 was rigid |