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What are the blimp's dimensions?
The GZ-20A size blimps (Spirit of Goodyear; Spirit of Innovation; Spirit of America) are 192 feet long, 55 feet in diameter, and 59.5 feet high, with 202,700 cubic feet of helium and a gross weight of 12,840 lbs.
How much does the blimp weigh?
Without any lifting gas, the empty ship (GZ-20) weighs about 12,840 pounds. Inflated with helium it weighs only 100-200 pounds, depending on the amount of fuel, payload and ballast aboard.
Why are the blimps so safe?
Unlike the great German Zeppelins of fifty years ago, the Goodyear blimps are filled with helium, an inert gas. Although Hydrogen is a better lifting gas, lighter and more plentiful than helium, it is terribly flammable, even explosive. Helium is found in the earth, mixed with other natural gases. The most significant deposits yet discovered are in northern Texas, Kansas and Colorado.
What is the blimp made of?
The Goodyear blimps in the United States are fabricated by Goodyear & Lockheed Martin. They are made of polyester fabric coated with neoprene rubber. They look shiny and metallic from a distance, but they are actually soft and flexible.
How often does helium have to be added?
The ships lose very little helium in normal operations, although the gas does have to be purified about twice a year by a Goodyear designed purifying machine. As the envelopes age and have a tendency to allow gas diffusion. The crew might have to add 10,000 cubic feet of gas per month. They buy the gas along the tour and add it as needed since none is carried along.
If the ship doesn't let off helium, how does it come down?
Inside the envelope are two air chambers called ballonets, one forward and one aft. They can be pumped up with air from the outside or allowed to deflate as the helium expands and contracts. Since air is heavier than helium, inflating or deflating the ballonets will add or subtract weight from the nose or tail, thus trimming the ship. Using the pilot controlled rudder and elevators the ship can fly up or down in the ocean of air and maintain its proper envelope pressure without having to drop ballast or valve off helium. The two hanging scoops behind the propellers are air intakes for the ballonets; the props force air into them when the pilot opens them up. When the ship is on the ground and the engines are off, auxiliary electric blowers automatically maintain the proper pressure in the ballonets.
Could the ship somehow get loose from its mast and float away?
The latching mechanism is designed to anchor the blimp in extremely strong winds, and failure is very unlikely. Should the ship somehow break its mooring, it would auto-deflate to contain the damage to the ship and prevent it from floating away.
How is the ship anchored when it's on the ground?
At the very tip of the blimp's nose is a steel ball much like an automobile trailer hitch. This ball locks onto a cup at the top of the portable mooring mast, which is taken along and set up wherever the ship is operating. The blimp is anchored to the earth only at this one point, so it is always free to rotate 360 degrees around the mast as the wind changes. This arrangement has held the blimp in hurricane-force winds on more than one occasion. The blimp will always point itself into the wind, like a weather vane.
What are those two ropes at the nose?
The nose lines are used to hold the ship's nose into the wind while it is being handled on the ground. The ship has so much sail area that it will become a little unmanageable if it is allowed to get off-wind, so two groups of three crewmen grab each line as the ship lands, run to the sides, and hold the ship into the wind at the direction of the crew chief. The ropes are allowed to hang down when the ship is flying, since there is no particular reason to tie them off.
What are those little round bags for?
They are ballast bags, each filled with twenty-five pounds of lead shot. They are put in or taken out from a little compartment at the rear of the car to give a final trim before take-off. The crew chief and the pilot calculate the weight of fuel and payload (including passengers). then add or subtract shot bags as desired. Pilots usually like to take off about ''four bags down", or 100 pounds heavy.
Why does the crew chief hold up that butterfly net when the blimp lands?
That's a little portable wind sock, and it gives the pilot a final check on the wind direction as he makes his approach. The airship always lands directly into the wind.
How many lights are there on the sides?
There are 7,560 on the three Goodyear Airships. The lights are custom made high brightness LED (light emitting diode) Light modules.
How does the night sign work?
Goodyear calls it the EagleVision, and basically it's a computer driven, electronic system which reads data and then sends out millions of commands to turn the lights on and off with different colors at the proper instant creating text and animations brilliant enough to be seen up to one mile away.
What type of engines do the blimps have?
The GZ-20's carry two fuel injected Continental I0-360's, producing 210 horsepower each. An altered version of this engine is used on the Pitts Special acrobatic airplane. The propellers are pusher Hartzells, constant-speed and reversible. They are custom-made for the Goodyear blimps.
How fast and how far can the blimp go?
The usual cruising speed is thirty-five miles per hour in a zero wind condition; all-out top speed is fifty-three miles per hour on the GZ20. As to cruising range: the ship can carry enough fuel to fly for twenty- four hours, although it rarely does so. When traveling cross-country the blimps fly wherever they go, and the crews try for an eight-hour day, or about 300 air miles.
What avionics do the ships carry?
All Goodyear blimps are FAA-certified for IFR (Instrument Flight Rules) flying, day or night. They carry two King 360-channel navcom radios, the usual light plane instruments, digital radar for keeping an eye on thunderstorms, transponder for radar identification, and a couple of instruments peculiar to blimps: manometers for watching envelope pressure and a helium temperature gauge. All Goodyear Airships carry GPS navigation receivers for precise navigation.
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