The advantage of aerostatic support from the top comes from a consideration that support from the bottom must not only support the payload weight, but must support the added weight of other supporting members.
This principle applies to the engineering of any tower.
Support from the top is not subject to this restraint, and automatically reduces earthquake liability.

What if the balloon pops? That almost primal fear may be to blame for the shameful state of airship engineering.
The failure mode of a stretched elastomeric ballon filled with compressed gas has startled many people in their infancy.
This image may have formed a new archetype, a fearful imagination which shadows the minds of many when they think of airships.
This phantom may have led to the vague impression of impermanence which clouds most minds in consideration of the applications of static lift.
Use of the principle in permanent constructions, such as in buildings, may help to rectify the popular fears.

Aerostatic application to construction does quite properly bring to mind the legitimate engineering concern, that continuous maintenance will be required to assure the constancy of an aerostatic support component.
There must exist a hazard in the background at all times, that some combination of circumstances will cause the lift to fail, bringing the building down in collapse.
Note the calculations of R.
Buckminster Fuller on this subject, in his proof that a dome large enough to enclose a city could also lift that city, by solar thermal effects alone.
This example shows that at least on the largest scale, constant tweaking and worrying with the lift with every breeze that blows, might not be an issue.
The dome over a floating city would no doubt have maintenance problems, but more of them would be related to cleaning the acres of glass than to the remote possibility of a catastrophic failure.

Proper engineering can indeed reduce the probability of catastrophic failure to very low levels.
The simple expedient of making an envelope robust enough so it is not appreciably damaged by small-arms fire removes one of our distressing possibilities.
That also takes care of bird collisions and hailstones, by the same token.
The natural threats of wind and lightning are left as the greatest real dangers, followed by the unpredictable risk of hostile military activity involving high explosives.
The last calls for the quiet comment that no type of structure has ever proved safe from attack; admittedly, the very possibility of spectacular catastrophe will always be a temptation to the infantile imagination of irresponsible soldiery.

Much of the worry of real-time maintenance of aerostatically supported structures is relieved by use of automatic machinery, such as trimming the lift to compensate for ambient temperature, and retensioning guys to adjust for shifts in the wind.
Though the simplification of Fuller's self-floating cities must be left in dreamland, aerostat-supported bottom-fixed structures should be designed to be largely independent of critical ground-level support, which is a function of social continuity in the society.
No such structure, for example, should depend on a continuous input of power from the electric mains to remain aloft.
Ideally, lift should not depend on outside power at all. Breaking off the discussion of aerostat-supported towers, we saw away the ground supports of such structures, and arrive at a consideration of vertically-arranged transportable constructions.
We are thinking heavy industry now.
There are processing stages which could benefit from vertical arrangement.
Feature a mining engine, smelter, foundry and rolling mill in vertical combination, which could produce refined metal at the mining site, while replacing its tailings exactly where they came from.
No roads would be needed to the mining site.
Many combinations of industrial processes are conceivable, generally using only solar power, with heat and steam the largest by-products.
The most urgent reason to use these plants is to prevent new road construction.
Their vertical orientation, however, suggests maritime applications also.

Lighter-than air structures are the one and only sensible design basis for windmills.
It makes little sense to erect a vastly overbuilt tower to support a spinning airfoil, just to derive power from the wind.
A trefoil or other spinning aerostat shape will ascend into the optimal winds without the expense of any tower construction, transmitting the torque through the downwind cable for use of a groundside generator.
Myriad other windmill designs are available for practical use, without building one tower.
Windmill towers are a waste, and should be considered obsolete from this point.
Similarly, aerostat structures must henceforth be considered for the support of large mirrors in the concentration of solar power, likewise for reasons of economy.

Whereaway?

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