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Aerostat, August 1994
Is it a UFO?
Story and pictures by E A Taylor
The UFO-looking, spherical airship, commonly known as a blimp, is currently the only one of its kind but if the designer, Hokan Colting, gets his way there will soon be many more floating around in the sky.
The 43' diameter, semi-rigid airship has the pilot and one passenger sitting inside the envelope. Only a helicopter-like landing skid and two stubwings, carrying the engines, are protruding from the otherwise completely globular airship. Two 50 hp Rotax engines give this airship a top speed of nearly 30 knots.
Spherical blimps cannot be used when speed is a necessary requirement, having a top speed of only 30 knots. But for a leisurely sightseeing ride over attractions such as Niagara Falls, the Grand Canyon or over the wildlife in Africa, when passenger comfort is much more important than speed, a spherical airship is the perfect vehicle.
This unique shape is a great attraction and rewarding promotional vehicle. When extra time is allocated for cross-country flights between cities and events, they perform as excellent flying billboards and camera platforms that no other aircraft today can match.
A purpose built sightseeing-ride/advertising airship was what Colting had in mind when he first started his research and development. Being an experienced commercial balloon/airship pilot for many years, flying both paying passengers and advertising, he wanted the advantages of a steerable lighter-than-air aircraft. However, he did not want the disadvantages of the 70 to 80 year old technology presently used to build traditional airships.
The technology for today's traditional blimps dates back to the 1920's; seeing only improvements with the use of newer fabrics and modernized engines. With the fins, rudders and elevators located at the back of their large cigar shaped envelopes, traditional blimps consequently have faced immense operational costs partially due to the required large ground crew necessary to assist the pilot with every take-off and landing.
Common leasing fees, ranging from $200,000 to $350,000 per month, have excluded all but the largest corporations from using traditional blimps as flying billboards. Along with this, their high operational costs have excluded them from capitalizing on the huge aerial sightseeing ride market.
The absence of fins and regular balloonets on spherical blimps make them considerably less costly to manufacture. With no preferred direction in the wind, they are simply tied down to anchors in the ground when "parked". This has eliminated expensive and complex ground handling and mooring equipment necessary for traditional blimps.
Another bonus for Colting's spherical airships is that only two ground crew personnel are necessary to assist the pilot. This factor has drastically reduced operational costs.
The current two-seater is the fourth spherical airship built since 1991, by Colting's company 21st Century Airships Inc., in Newmarket, Ontario, Canada. The previous three were rudimentary prototypes used as flying test platforms for the now patented technology that allows steering and altitude controls to be achieved without fins, rudders and elevators. All prototypes had the gondola suspended underneath the envelope.
By positioning the gondola to the inside of the envelope for his fourth airship, three remarkable feats have been achieved.
Firstly, the drag coefficient has been reduced from 0.25 to 0.18, resulting in a considerable reduction in the horsepower that is essential for reaching the modest speed of 30 knots.
Secondly, the cabin is more spacious when placed inside the envelope, making it comfortable and quiet for the passengers and pilot; an important feature when applied to future sightseeing blimps.
Thirdly, the appealing UFO-look obtained presents passenger, as well as advertisers, with an unequaled allurement that fascinates and entertains as it circles and hovers overhead.
The prototypes, along with the current airship, have all employed two envelopes. The outer one is load bearing and the inner one contains the helium lifting gas. The inner envelope is manufactured using a patent pending process and is so well sealed that, even after 7 weeks of test flying, no "topping up" was necessary; a very cost saving feature since helium runs approximately $200 per 1,000 ft3 (equals 60 lbs. of lift).
Colting's current two-seater is used as a proof-of-concept demonstrator and model for a 10-passenger sightseeing airship presently being developed. This new blimp may see its first flight as early as the summer of 1995, providing financing arrangements currently being negotiated are completed in the near future.
Finless spherical blimps, utilizing state-of-the-art technology, are truly airships of the 21st century.
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