Heating the air in this blimp is accomplished by three sources of energy:

1. A Kernmantle rope with an electric wire in or attached to it, tethering the blimp and powering its heating (and propulsion) system.

2. Solar heat - designed with a clear top and lightweight dark leaf inside, during sunny days the blimp is heated directly.

3. Wind power - once up in the air, an AWES (airborn wind turbine) will supply power, either back through the tether to be consumed back down on earth, or to be stored in airborne batteries and used when needed.

An extended version of the blimp would have an ionizer or a Van-De-Graaff generator (grounded through the tether), so that the air is thinned even further.
-- pashute, May 14 2015

With batteries made from this http://www.thestar...._for_batteries.html
Only meanwhile, until the "lighter than light" version promised at the end of the article is out [pashute, May 14 2015]

Clement Ader (Thanks [MB] !) https://en.wikipedi...i/Cl%C3%A9ment_Ader
includes links to webpages of his flying machines [pashute, May 20 2015]

Disc loading http://en.m.wikiped...g/wiki/Disk_loading
[EnochLives, May 20 2015]

Put water inside the blimp envelope, coat the inside of the blimp with an appropriate reflector, and then use the tethered electric power to make microwaves to efficiently convert the water to steam, and keep it hot. The steam then inflates the blimp (and is significantly lighter than ordinary hot air, too).
-- Vernon, May 14 2015


Because of the tether, the propulsion system will propel it around in a circular, or perhaps dome shaped path. That would be perfect for football games, less good for transatlantic crossings.
-- bungston, May 14 2015


In 1903-04, the French aviation pioneer Clément Ader conducted trials of several electrically-powered aeroplanes which flew at the end of a long power- carrying tether up to 2km in length. Electric motors in those days were heavy, but were still lighter than the available liquid-fuelled engines and had the advantages of reliability and easily-controllable speed.

Ader successfully flew his aircraft (the Electron, the Magnéte and the Voltaire Bis - the last of which had two motors) on a number of occasions, in circuits around a central tower which provided the power and payed out the cable using a sprung reel. His longest flight was just over three hours, during which he covered some 120 miles - easily beating the current distance and time records.

Ader's aim was not to develop electric aircraft, but to use his system as a dependable test-bed for studying the performance of various aircraft designs, in preparation for what he predicted would be the development of lightweight, reliable liquid-fuelled engines.

To minimize the weight and drag of the tether, he used only one conductor; the return path was made with a much shorter cable which ended in a series of copper chains. This shorter cable dragged along the ground directly below the aircraft to provide an earth connection.

His diaries record over 700 flights in these three aircraft, making him the most experienced aviator of the day.
-- MaxwellBuchanan, May 14 2015


[Max] I appreciate how you always find the most obscure and interesting historical facts. I usually feel that I have to look them up to verify and to learn more, which often ends up being very difficult.

Regarding the electric airplane, what really interests me (but I wasn't able to find more details on) was how he got a solid ground connection with dragging copper chains. If there is enough chain dragging to allow for altitude changes and to provide enough contact for a low resistance electrical connection, it seems like it would provide way to much drag and have an unacceptable risk of snagging something.
-- scad mientist, May 15 2015


Clever.

Interesting about the electrical plane Max. I think this Ader guy had a bad press agent as it's definitely a part of aviation history that doesn't get much mention. I'd never heard of him.
-- doctorremulac3, May 16 2015


//how he got a solid ground connection// I believe he used high voltage (and low current), both for this reason and to keep the tether cable as light as possible. I don't know if his motors ran off the high voltage, or if there was a transformer (which, given the transformer technology of the time, would have been quite heavy).
-- MaxwellBuchanan, May 16 2015


Incidentally, although the idea of an electric plane running off an extension lead is generally considered risible nowadays, there may be a recreational market.

Consider those water-jet packs, that run off a hose from the floating base unit. They're considered great fun despite being tethered.

So, I wonder how feasible it would be to build a man- carrying twin-motor, twin-rotor backpack machine that took its power from a ground tether of, say, 100ft. It'd be great fun, and potentially useful for (for instance) inspecting high structures.

Reliability would be pretty high. Stability could be fly-by-wire (based on existing drone technology). A backup battery, either onboard or at the base station, would provide a few seconds of power for a safe descent in the event of a power loss.
-- MaxwellBuchanan, May 16 2015


Any ideas on the power needed to keep a man hovering?
-- MaxwellBuchanan, May 16 2015


//Any ideas on the power needed to keep a man hovering?//

See link for a simple description of actuator disc theory. The penultimate equation suggests about 5kW is required to lift a vehicle of 150kg using a lightly loaded rotor. You should probably double this to account for aerodynamic inefficiencies.

Hovering is difficult, but I was actually expecting the power to be somewhat more than this.
-- EnochLives, May 20 2015


5kW is OK, in fact even 10kW would be doable from a domestic supply, via a reasonably-sized cable. I too would have expected it to be higher.

So, based on 10kW, it's feasible to build an electric hovering thing that's tethered to a domestic supply. I'd buy one.
-- MaxwellBuchanan, May 20 2015



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