Mooring mast

[6] The structure known as the ‘mooring mast’ was invented over 100 years ago when a solution was needed for ground handling problems that resulted in many airships crashing, being deflated or being significantly damaged.

In their book, González-Redondo & Camplin[7] discuss the first attempted solution that partially overcame the ground-handling difficulties, a shed that floated on water which could turn freely and automatically align its long axis with the direction of the wind.

In an attempt to avoid the various issues with loading airships into their sheds and to prevent further accidents, engineers would often deflate their blimps, accepting the financial loss and time cost of any damage caused by dismantling it out in the open.

The use of a metal column erected on the ground, the top of which the bow or stem would be directly attached to (by a cable) would allow a dirigible to be moored at any time, in the open, regardless of wind speeds.

Additionally, Torres Quevedo's design called for the improvement and accessibility of temporary landing sites, where airships were to be moored for the purpose of disembarkation of passengers.

[11] Mooring mast technology following Leonardo Torres Quevedo's design became widely utilised in the 20th century as it allowed an unprecedented accessibility to dirigibles, negating the manhandling that was necessary when an airship was placed into its hangar.

Due to his inventions, mooring masts were designed simply to allow airships to be docked on ships, land and even atop buildings, all while withstanding gusts and adverse weather conditions.

High and low masts were experimented with by French, English, American and German engineers in order to determine which technique was the most effective in terms of stability, cost, ground-handling and their ability to allow blimps to weathervane and therefore minimise outdoor-related damage.

Low masts required a number of ground crew members to constantly attend to the changing directions of the wind as they attempted to re-inflate and repair the airships.

At this point, two side wires – or ‘yaw guys’ – were also connected to cables taken from the nose of the airship to pulley blocks some hundreds of feet apart on the ground and thence to winches at the base of the mast.

[15] A gangway, like a drawbridge, which could be drawn up flush with the nose of the airship, was then let down with its free end resting on the parapet of the platform running round the mast.

Similar masts were proposed at sites in Australia, Ceylon (now Sri Lanka), Bombay, Keeling Islands, Kenya, Malta, at Ohakea in New Zealand, and in South Africa.

In some places the stub mast was mounted on rails and could be drawn into the airship hangar, guiding the nose of the ship while the tail was controlled by the carriage attached to the rear gondola.

Airships designed for landing on the ground had pneumatic bumper bags or undercarriage wheels under the main and rear gondolas (or tail fin).

Long experience in handling airships in all sorts of conditions was valued and innovations or significant changes in practice were unlikely to be adopted unless clear advantages were apparent.

In one famous incident captured on movie film in 1932, during the landing of the US airship Akron, three men were carried off their feet in this way, two to fall to their deaths after a short time.

Over time the airships USS Shenandoah, Los Angeles, and Akron all moored to the mast mounted at the stern of the ship, and operated using her as a base for resupply, refuelling, and gassing.

[23][24] Around 1925, the Royal Navy considered the monitor, HMS Roberts, for conversion to a mobile airship base with a mooring mast and fueling capabilities, but nothing came of this proposal.

[25] By 1912, dirigibles were widely acknowledged as the future of air travel and their flexibility as both civilian transporters and military vehicles meant that continual advancements were made to both airships and their mooring masts.

The mooring mast or “open-mooring” allowed airships to accompany armies in their manoeuvres through a safe, quick and relatively inexpensive ‘universal’[7] docking system that worked well for all types and sizes of blimps whether they were non-rigid, semi-rigid or rigid and which could withstand meteorological events.

However, considerable advancements made in the construction and operation of both dirigibles themselves and mooring technologies meant that airships were soon developed by civilian companies and other government departments.

However, an obvious drawback to this mooring site is the lack of adequate terminal facilities, with passengers expected to walk down a plank extended from the blimp to the platform on the 102nd floor.

[2] Developments in aerodynamics and structural designs as well as greater access to more advanced materials has allowed for airship technologies to become much more sophisticated over the past 30 years.

[27] Since the Hindenburg disaster of 1937, whose tragic docking remains an icon of aerospace gone wrong, modern-day airships are now designed as hybrids of lighter-than-air and fixed-wing aircraft.

At a fraction of the cost and fuel of regular aircraft, modern dirigibles can carry enormous payloads without requiring such vast amounts of tarmac necessary for conventional air travel.

As they traditionally occupy great amounts of space, many engineers now design mooring masts as easily foldable and portable stands with long legs for adequate ground-stability.

In terms of indoor dirigibles, lightweight masts are just as stable and portable, accommodating non-rigid blimps up to five metres and successfully limiting yawing, pitching and rolling.