I want that blimp!
It was at West 2nd Street and South La Brea Avenue, in Los Angeles, CA
Okay Charlie, what kind of gas pumps are those?
Robert, it's not a blimp it's a dirigible as can be seen by the ribs and stringers making up the frame. That type of airship has several gas bags or cylinders inside of a metal frame and the helium can be compressed back into storage cells to decrease lift on a hot day. The gondola and engines are connected directly to the frame. They use sand as ballast.
Blimps are actually single celled airships with two internal bladders or ballonettes (little balloons), one front and one rear. air is pumped into the bladders by ducted tubes from the twin propellers much like a fish bladder. When the front bladder is deflated and the rear one pumped up it makes the back end of the blimp heavier than the front and the nose points up. This action keeps the skin tight without wrinkles and can change balance in order to climb and dive or ascend or descend. The elevators and rudders also aid in changing direction as do the more modern blimps with rotatable engines that can vector thrust. The rest of the air bag is filled with helium and if they have too much lift they will get too high and must dump or valve off helium in order to keep from bursting the air bag. The gondola is supported by a twin catenary curtain hung from the upper surface of the rubberized fabric skin of the air bag or envelope because there is no framework So you can say it's sort of like a submarine that flies through the air. The blimps use sand as ballast. Blimps have a smooth skin because there is no framework underneath to cause horizontal lines in the outer skin.
When I was teaching illustration at the college we went on field trips to the blimp field in Carson California and they let us climb all over it. I gave assignments and we made a story board of how a blimp flies and then each student made one drawing of one of the parts detailing the systems. Then I made up a set for each of the students for their portfolio. I gave a talk at the Old Bold Pilots breakfast as a guest of the late Ralph Ricks and they enjoyed it very much. Pilot Jack Nickolery was there and a few weeks later I was invited to go for a blimp ride but I was out of town that day and so Howard Genrich got to go instead of me.
So again the title is correct, it is a dirigible and not a blimp.
I always heard that, despite the similarity, the word "dirigible" has nothing to do with "rigid". Rather, it's a French word meaning "steerable". A dirigible is any powered lighter-than-air aircraft that can be steered, as opposed to a free balloon that merely drifts with the wind. Dirigibles come in two flavors: blimps, which are non-rigid gas bags as Frank describes; and zeppelins, named for Count (Graf) von Zeppelin who first designed them around 1901, which have rigid frameworks with their gas bags inside. An airship like the one in the picture with Frank's speedster is a non-rigid blimp. An airship with structure, as the little model in the old picture would be if it had an engine, is a zeppelin. Both are dirigibles because they can be steered.
Rigid airships used water as ballast.
A photograph of the Graf Zeppelin LZ-127 dropping some of it's water ballast.