The British R.38 class, embodying the latest improvements in airship design outside Germany, gives a gross lift per airship of 85 tons and a net lift of about 45 tons. The capacity of the gas bags is about two and three-quarter million cubic feet, and, travelling at the rate of 45 miles per hour, the cruising range of the vessel is estimated at 8.8 days. Six engines, each of 350 horse-power, admit of an extreme speed of 70 miles per hour if necessary.

The last word in German design is exemplified in the rigids L.70 and L.71, together with the commercial airship 'Bodensee.' Previous to the construction of these, the L.65 type is noteworthy as being the first Zeppelin in which direct drive of the propeller was introduced, together with an improved and lighter type of car. L.70 built in 1918 and destroyed by the British naval forces, had a speed of about 75 miles per hour; L.71 had a maximum speed of 72 miles per hour, a gas bag capacity of 2,420,000 cubic feet, and a length of 743 feet, while the total lift was 73 tons. Progress in design is best shown by the progress in useful load; in the L.70 and L.71 class, this has been increased to 58.3 per cent, while in the Bodensee it was ever higher.