The hulls were strengthened and made more rigid, yet lighter, machine guns were mounted at proper points of vantage and bomb dropping apparatus so perfected that heavy loads of explosives could be carried in absolute safety, yet instantly released and with remarkable accuracy. An observation car was added to each new ship.
The Zeppelin Observation Car
This car was one of the most unique inventions developed during the war. It could be lowered with an observer aboard, fully one kilometer (3,280 feet) below the Zeppelin. Here the observer could get his bearings while his ship lay far above hidden in the clouds. The ship could fly or drift above the clouds to a point directly over the spot to be bombed, then by lowering the car with the observer through and just below the clouds, he was able to direct both the operations of the ship and the bombing. A telephone connection ran up through the supporting cable. He was able to signal for bomb releases and navigate so efficiently that any objective could be attacked without danger of the enemy seeing the Zeppelin lurking behind the clouds.
Another Zeppelin, the L-20 was delivered to the navy early in 1916. It had hydrogen capacity of 1,271,160 cubic feet (36,000 cubic meters) though the diameter was the same as the others. The L-20 carried a useful load of 37,478 pounds (17,000 kilograms), and an increase of 1,312 feet (400 meters) over their ceiling and made the same speed with the same horsepower.
During the year Zeppelin delivered seven more ships of this type, but possessing greater efficiency. The navy received five of them and the army two.
Maybach Airship Motor of 145 Horsepower, 1911.
Maybach Airship Motor of 180 Horsepower, 1913.