The history of the airship is one of both awe-inspiring success and spectacular failure. The awe was generated from the sheer size of these floating ships, and for the time, the impressive performance in payload and speed they produced. Likewise, the failures were equally, if not more captivating, since the spectacle produced by the crash of a giant behemoth filled with combustible gas would surely be hard to ignore. The infamous Hindenburg disaster in 1937 and its images have been used metaphorically for depicting ill-fated and ill-advised aerospace ventures for decades. Following that calamity, the development and use of lighter than air (LTA) ships was significantly curtailed, but not abandoned entirely. Looking forward, it appears that perhaps some of the technology that advanced airplane development rapidly ahead of LTA aircraft may now be utilized to exploit the unique characteristics and capabilities of these ships.
Applications – Past and Present
The fundamental utility of the airship has not significantly changed over the past century: it can be used for observation of all manner of the electromagnetic spectrum and to convey a payload. This would include advertising and public promotions and demonstrations. Consider that the Goodyear Tire and Rubber Company of Akron, Ohio has been advertising from their blimps for over 90 years. In the early 20th Century, the development of the airship was advancing due to its significantly superior performance compared to aircraft of the time. It is clear from history, however, that due to a confluence of rapid technological innovations with the airplane and other related technologies, such as rockets and satellites, the airship became displaced by other machines that were better in getting the job done. It has found niches that have allowed it to perform various tasks throughout the past century, nonetheless, and the airship still captures the interest of aerospace engineers and enthusiasts. Accordingly, there has been an “unexpected and dramatic renaissance” in LTA ships based upon unique and unconventional shapes and hybrid propulsion systems. The application of modern LTA designs fall into these following broad categories:
- Tourism (both premium luxury and eco-tourism)
- Surveillance (civil, military, agriculture, environmental, etc.)
- Counter Insurgency/Terrorism, Piracy, and Border Control
- Special Military Operations (ultra-high altitude and duration, electronic relay)
- Freight and Lifting Operations (flying crane)
The experts are mixed on the economic practicality of some of these, particularly with respect to passenger and freight operations; however, there exists some viability with the right mix of technology and innovation. Examples include using aerodynamic shapes that produce lift, autonomous operation, and hybrid electrical power systems that both consume hydrogen in fuel cells and produce hydrogen by way of solar cells. These technologies can be expensive to develop, however, and except for government sponsored research and operational requirements, finding the capital to move forward means finding a market. Nevertheless, some key civilian applications of airship undergoing study include freight transport, mobile phone antennas, tourism, and surveillance. All have their roots in past applications of the airship.
Transport
In recent years, interest in airships have seen a comeback to transport cargo to remote and distant areas that are not easily accessible by roads such as Canada and the Artic. Typically, these remote areas are serviced by airfreight, sea shipments, and ice road. Until recently, these remote areas could rely on the winter ice roads, but climate change impacts on the melting ice has led to uncertainty in their continued use. To improve access to these remote areas, Lockheed Martin has a contract to build 12 heavier than air airships that can carry up to 20 tons of cargo. There is also a growing interest to using airships in a cruiser and feeder system to connect major populated areas.
Mobile phone networking
The use of mobile phones has grown tremendously and there is ongoing research on the use of High Altitude Platform Systems (HAPS), which would replace earth bound antennas and reduce radiation effects drastically. According to a Swiss inventor, an unmanned aircraft outfitted with a mobile phone antenna would be mounted on a solar powered airship providing the platform with the technical equipment. Note that Union balloons in the Civil War telegraphed Confederate positions to their artillery gunners for accurate fire.
Science Experiments
LTAs have been used for science from the earliest days of ballooning; in 1794 an English scientist named Jeffries ascended to 9000 feet making measurements of temperature and pressure. Today, owing to their slow speeds and stability, airships are also being considered to serve as platforms for airborne gravity measurements. Krasnov, Sokolov and Rzhevskiy used an airship to carry gravimetric equipment. The slow speed and altitude provide a good platform for the surveys, however, such a system provided insufficient accuracy due to the recurrent inertial accelerations which could be improved by maintaining constant altitude. Nevertheless, the concept proved workable.
On-demand Hypercommuting
Another potential modern use of an airship that is being researched is to provide an on-demand commuting vehicle across congested areas such as the San Francisco bay area. They propose a “semi-rigid hulled lighter than air (LTA) airship” with a carriage slung below it with four tethers whereby the airship provides the lift and loitering capability, while the cycloidal rotors provide the lift for the payload and propulsion. The customer vehicle drives into the carriage where it is secured and then transported by the airship to its destination. It is anticipated that such a system would carry up to five passengers and cut travel times in congested traffic areas, however, the cost to operate such a system appear prohibitive at this time.
Military and Defense Applications
As evidenced throughout the development of the LTA aircraft over the decades, militaries have found innovative and viable uses for these devices both in defensive and offensive operations. Configurations include both manned and un-manned, tethered and free floating, and all sorts of structures to include balloons, blimps, and rigid and semi-rigid airships. Some were effective weapons of war, others did not obtain the desired results or were quite dangerous for the crews that manned them. Even today, 117-foot-long unmanned balloons called aerostats are common sites in the skies over Afghanistan, providing 24-hour monitoring and video surveillance. Defense research agencies are continuing advanced study and deployment of LTAs as this application provides a capability desired by both military units on the ground and senior policy makers at the national level.
There are a multitude of new and exciting ideas for airships of the 21st century utilizing cutting edge technology in design, control, automation, and power production. The problems airships face is that of economics and competition: new technology is expensive and alternative air vehicles such as UAVs seem to be attracting much more interest. While science, military, and security applications for LTAs are prevalent today and appear to have a secure future, many experts in commercial aviation do not see a robust market for airship freighters except niches such as remote jungle or arctic locations with limited or no infrastructure. As with the airships of the past, opportunity, innovation, competition, and the market will ultimately determine the future of these majestic ships.
Fly 'n Things 