Anti-Aircraft Defenses Compel Zeppelins to Fly Higher
The Allies meanwhile had developed anti-aircraft defenses and their airplanes possessed greater climbing ability. To meet these new conditions the airships were continuously compelled to fly higher. They also required speed greater than the average of 54 miles per hour (25 meters per second) because while navigating over the North Sea they frequently encountered winds of from 33.5 to 40 miles per hour (15 to 18 meters per second).
To meet these conditions the L-30 was built ([Plate 9]). It had a gas capacity of 1,942,000 cubic feet (55,000 cubic meters) and was nearly twice as large as the original 1,129,920 cubic feet (32,000 cubic meters) four motored ships. The L-30 was ready in May, 1916. It was almost perfectly streamlined. The long cylindrical hull, so convenient from a production standpoint, had been abandoned. The L-30’s stern tapered gracefully to a fine point. It was driven by six 240 horsepower Maybach motors, arranged practically as before. One was located in the forward gondola with a direct drive propeller, another three motors in the rear gondola, one with a direct drive and two others each in a separate gondola located opposite each other on the sides of the hull amidships, so as not to interfere with the efficiency of the propeller in the rear gondola. The L-30 carried 63,933 pounds (29,000 kilograms), about 45% of its total lift. Other Zeppelins of her class had a useful lift of 50% due to better design and superior materials. This represented a marked advance, as the preceding types lifted only 37% of their weight. The ceiling had been increased, too, by more than 3,280 feet (1,000 meters). They could now ascend from 11,800 to 14,750 feet (3,600 to 4,500 meters), depending on the load and weather conditions. They made a speed of 63 miles per hour (28 meters per second).
Maybach Airship Motor Type HSLu of 240 Horsepower, 1915.
Maybach Airship and Aeroplane Motor Type Mb4a of 260 Horsepower at an Altitude of 10,000 Feet, 1918.