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Technology Spotlight: Follow along each day as NAA technology expert Al Robbins posts and comments on one of the >4000 United States patents related to lighter-than-air (LTA).
  • 19 Oct 2013 7:06 AM | Deleted user

    Todays patent is Watt’s only U.S. patent.

    The patent’s single page of text includes three claims.

    (I’ve attached a copy of the full text for the reader’s convenience.)

    NOTE: The patent discloses a means of preventing an airship from 

    “bobbing” at the mast.There is no indication that these movable 

    mooring connections are used while mooring (or unmastingthe airship, 

    or assist in starting or stopping the airship as it rotates around the mast 

    in response to shifting winds. N.B. The third claim includes indicating/

    recording devices which measure the force exerted by each of the 

    hold-down lines.

    The parts shown in red are missing from the google/patents

    OCR version; I've corrected all the other conversion errors.

  • 18 Oct 2013 9:48 AM | Deleted user

    Todays patent is one of Arnstein’s31 U.S. patents,

    one of four with co-inventor Helma.

          “In constructing large bulkheads which are built up from 

    a plurality of individual wires, considerable difficulty has been

    experienced, not only in properly positioning the wires during

    the manufacture of the bulkhead, but also in securing the wires

    together and applying the proper tension thereto so that the 

    strains imposed upon the bulkhead will be fairly distributed through

    the several wires. Even after the bulkheads have been constructed

    by former known methods, there still remains the laborious task of 

    properly securing the bulkheads in the main transverse rings of

    the rigid airship. By former practices this operation entailed

    considerable time and labor, as well as presenting numerous

    difficulties in the way of handling, tensioning etc.

          It is an object of the present invention to provide an improved

    method for constructing flexible bulkheads for rigid airships, 

    which method avoids and overcomes the foregoing difficulties of 

    prior known methods.”

    NOTE: The inventors describe a device to weave, transport, position,

    and install huge (wire) bulkheads  in Zeppelin-type rigid airships. 

    (One such “Jig” might possibly be used to assemble more than one 

    bulkhead; they don’t indicate how many different sized jigs would

    be required, or claim that their jig might be adjustable in size.)

    Goodyear-Zeppelin only built two rigids ( the AKRON and MACON) 

    after this invention was disclosed. (Perhaps someone knows if the 

    Germans used such a device in constructing the HINDENBERG and 


    The USPTO has assigned four classifications:

     METAL WORKING    29/467 (Sequentially associating parts on 

                                            stationary aligning means),


     AEROSPACE             244/125 (Airship hull construction), and


    No modern patents cite this patent. 

  • 17 Oct 2013 11:22 PM | Deleted user

    Todays patent is the second of Pennock’s three inventions related 

    to collecting atmospheric electricity.

         “The objects of my invention are, 

       the providing of the balloon with an envelop or gas container,

    which is elongated in shape and which will freely turn in the air 

    as it may be acted upon by the wind or air currents;

       to keep the end of the balloon or envelop which is of least 

    transverse cross sectional area toward the direction from which 

    the wind is blowing;

       to provide the balloon or gas container with a stationary vane 

    or rudder, by means of which the forward and smaller end of the 

    balloon is kept against the wind;

       to provide the envelop with side wings or planes, so arranged as 

    to assist in elevating the balloon to high altitudes, and to utilize the 

    force of the wind or air currents in lifting the balloon;

       to provide a means whereby the elongated envelop or gas container 

    is maintained in a substantially fixed plane, with the forward end 

    elevated a little above the level of the rear end, so that the side wings

    or planes may have a kite effect and lift the rear end of the gas container

    or envelop, should it tend to drop;

       to attach the anchor line or stay to the bottom of the balloon or gas 

    container in such a manner that the forward end of the balloon will 

    always be kept at a little higher level than the rear end, and to further 

    provide means whereby the point of the virtual attachment of the stay

    or anchor line to the bottom of the balloon may be shifted forwardly 

    or rearwardly whenever the balloon substantially deviates from its 

    normal position;

       to swivel the balloon to the anchor line or stay so that the balloon 

    will turn as the wind may change without being required to twist the

    whole largest dimensions substantially midway length of the anchor

    line; and

       to make the envelop or gas container of a suitable, thin, metallic 

    material, so that it may act as a collector of atmospheric electricity and 

    to conduct the electricity which may collect upon the envelop or gas 

    container to the earth, to be used for any useful purpose.

    NOTE: Interesting concept. The patent doesn’t discuss the construction 

    of the conductive umbilical (single, primary tether line),  how the rotary

    joint might survive intense currents, or when, why or how the

    balloon would be hauled down. 

    Pennock describes, but doesn't claim a procedure for initially filling

    the balloon and an overpressure relief valve, but no other provisions

    for maintaining pressure or buoyancy, or controlling aerodynamic lift.

    N.B. Pennock’s preferred design is for a rigid metal envelope, 

    presumably strong enough to be filled with, and drained of, water 

    without damage or distortion.

    This patent is cited by four modern patents:

      2,431,938  Kite balloon,

      2,960,298  Kite,

      4,117,486  Buoyant chaff, and

      WO2012154873  Atmospheric electricity collector.

  • 16 Oct 2013 2:22 PM | Deleted user

    Todays patent was Admiral Rosendahl’s last patent issued before 

    he retired from the Navy. 

    All three of his patents involve mooring airships.

         “It has long been realized by experienced airship operating 

    personnel that the so called flying moor method of landing to 

    either a high or low mast falls short of furnishing either a 

    sufficiently universal mooring method or a sufficiently safe one, 

    the major weakness in the flying moor being its lack of

    adequate vertical control during the mooring operation.

          Purely manual ground landing of rigid airships in the United 

    States was discontinued a number of years ago although the landing

    and horizontal transfer of a rigid airship to the mooring mast has 

    been accomplished in a gusty wind of from 22 to 30 knots velocity, 

    by manual methods. In this ground landing and horizontal transfer

    method the weak element now seen is the lack of sufficient control,

    principally vertical, after the ship reaches the ground. There is a 

    definite limitation to the number of men that can be used on the 

    control car hand rails and the amount of force which men can 

    exert on the control car is altogether out of proportion to the size 

    and mass of the ship.

          It is, therefore, an important object of the present invention to 

    provide a properly designed landing car to take the place of the 

    forward car party and to increase materially the control that can 

    be exerted at that point.

          Another object of the invention resides in the provision of a 

    method of mooring an airship to a conventional mooring mast 

    including the step of temporarily attaching the forward control 

    car of the airship to a mobile landing car that takes the place of 

    the forward car party.

    NOTE: This is a method patent, exclusively for mooring large airships 

    to a fixed mast. None of the claims involve procedures for unmasting or 

    docking the airship. (Rosendahl never gave up on rigid airships;

    although none of the four approved claims specify applicability to 

    semi-rigid or rigid airships.)

    Only the first claim involves a “mobile ground car” to holds the ship 

    near the ground as it is pulled up to the mooring mast; it also specifies 

    the ground car is to be removed once the airship is moored.

    Claims 2 through 4, refer to a “mobile stub mast” which is first attached

    to the forward control car (or the bottom of the ship), and then the ship 

    with the mobile mast attached is pulled to the mooring mast. (No mention 

    of subsequently removing the stub mast.)

    The patent is cited by nine modern patents:

      2,704,193  Method and apparatus for mooring airships

      4,238,095  Method of and apparatus for anchoring airships and

                        propulsion means for airships

      4,272,042  Airship and associated apparatus and method for

                        anchoring same

      4,529,152  Devices for maneuvering helicopters on a ship's deck

      5,398,635  Floating airport

      5,516,065  Landing and anchoring mechanism for an airship

      6,019,312  Airship tail fin construction for improved control

      7,275,714  Airship docking mechanism

      WO2007053216 Airship docking mechanism

  • 15 Oct 2013 11:50 PM | Deleted user

    Todays patent was Schiavone’s only U.S. patent.

      One of the main objects of my invention is to produce a type of 

    self-buoyant air vehicle which shall be practically, to all intents 

    and purposes, permanent in character in the sense that after it is 

    duly prepared and charged with the buoyant medium, it will 

    remain operative indefinitely, since the original supply of buoyant

    gas is retained intact. This I accomplish by inclosing the lifting 

    medium, (a gas lighter than the atmosphere, and hydrogen by

    preference,) in sealed receptacles or floats, upon and between

    which the framework of the structure is supported. I am enabled

    to accomplish this desideratum, and at the same time dispense with

    both steering apparatus and ballast as heretofore used and 

    understood in the art, by an important and distinguishing feature 

    of my invention, which consists essentially in varying the specific 

    density of the floats by means of compressed air introduced into 

    compartments therein, said compartments being separated from the

    lifting medium by flexible diaphragms whereby, the weight of the 

    apparatus may be increased or diminished to cause it to ascend or 

    descend vertically, or its center of gravity may be varied so as to 

    utilize centripetal force in guiding it laterally and horizontally in 

    the atmosphere as hereinafter more fully set forth.”

    NOTE: Once again, the Google OCR generates gobbledegook and 

    omits complete paragraphs. (It quits half-way through the 44th claim, 

    doesn’t even try to read the 10th and final page).

    Curiously this seminal patent is cited by only one modern patent
    8,091,826 "
    Aerostatic buoyancy control system". 
    Individual claims 

    cover single, twin and multi-hulled airships. Nearly all of the fifty-eight 

    claims start, “In aerostatic apparatus substantially such as 

    designated,” and end ,“for the purpose described”. (CYA phrases, 

    which mean you better read the entire patent before you waste 

    your money with the USPTO.)

    The USPTO neglected to assign classifications covered by many of 

    the patent's claims:

     244/94 {Ballast storage and release),

     244/95 (Ballast making),

     244/96 (Airship control),

     244/125 (Airship hull construction),

    244/128 (Airship gas cell construction and arrangement),

  • 14 Oct 2013 9:18 AM | Deleted user

    Todays patent is one of Krell’s twelve U.S. patents,

    one of six related to docking or mooring airships.

        “According to my invention the ballast member is supported upon

    a suitable truck adapted to follow the movements of the dirigible 

    in a horizontal direction. In order not to impair the mobility of the 

    truck by unnecessary weights, it is necessary to keep the travelling

    weight of the loading member as low as possible. According to

    another feature of my invention this is attained by the cable carrying

    the loading weight not being directly attached to the rear portion

    of the dirigible, but by being passed over a pulley attached to the 

    underside of the dirigible. In this way only half the ballast is 

    necessary for damping or steadying the vertical movements of the

    dirigible than would be necessary in case of direct suspension. 

    In this arrangement double the path of the ballast weight corresponds 

    to single the path of the tail of the dirigible in the vertical, so that the 

    damping action becomes very sensitive. The loading member is

    preferably composed of a number of chains combined into a tassel. 

    In this way it is possible to compose the loading weight in such a 

    manner, that the ballast increases or decreases during the ascent 

    and descent of the dirigible in accurately predetermined steps or 

    stages, for instance in an arithmetical series.”

    NOTE: Krell’s first claim suspends his “tassel of chains” directly from 

    the tail of the dirigible. The remaining seven claims all suspend the tassel 

    from a cable passing over a pulley mounted on the tail of the dirigible. 

    N.B. The patent doesn’t discuss how the tassel, or the cable can be 

    attached (or released) from the ship’s tail while mooring or demasting. 

    Perhaps more importantly, the inventor doesn’t discuss the ship 

    modifications required to permit all mooring ballast being suspended 

    from a single point near the tail, without permanently distorting the hull.

    By the mid-20s, the rigid airships were several hundred feet in length. 

    Assuming a typical Zeppelin-shaped hull, such a suspension from the 

    tail or the bottom fin, would help counteract the rolling force as the

    ship swung into the wind.

  • 13 Oct 2013 9:13 AM | Deleted user

    Todays patent is Basenach’s only U.S. patent.

    Basenach and his co-founder (then Major) Hans Georg 

    Friedrich Gross, designed and produced five semi-rigid 

    airships between 1908 and 1918. The M1, M2, M3, and

    M4 were modified and improved repeatedly during the war.

         My present invention relates to an anchoring arrangement 

    for air-ships, and has for its object to provide improvements whlch

    ensure that thereby the air-ship is effectively protected against 

    accidents caused by violent winds.  In consequence of my novel 

    arrangement the anchoring action may be easily and readily 

    carried out. My invention consists in providing an anchoring point

    beneath the forepart of the ship as, for instance, on the prow of the

    keel frame or beneath the front car, and pivotally joining this

    anchoring point directly to a suitable earth-anchor, whereby the ship

    is enabled to vertically oscillate and horizontally revolve about this

    pivotal anchoring joint. As a suitable means for effecting this 

    pivotal anchoring joint I may use a universal joint, a ball joint, 

    Cardan Joint, of which one part is directly, or by means of an 

    intermediate member, secured to the anchoring point of the air-ship,

    while the second part of said joint is directly, or by means of an

    intermediate member, secured to said earth anchor. Instead of 

    providing said anchoring point at a downward projecting part of 

    the ship prow, in order to allow the ship the necessary revolving 

    and swinging play, I may dispose the said anchoring point directly

    beneath the forepart of the carrying body of the ship and raise the 

    earth anchor to such a height that the necessary revolving and 

    swinging play is secured. Or I may provide the carrying body of the

    air ship with a downward directed rigid structure the end of which

    is then pivotally connected to the earth anchor which need not

    project above the ground.”

    NOTE: This is the only U.S. patent issued to either Nikolaus Basenach

    or Hans Georg Friedrich Gross. (Gross, retired as a Major General in 

    1918; Basenach is usually identified as a Balloonist, no mention of

    military service). Unfortunately the Gross-Basenach Company’s 

    semi-rigid designs had no more luck after the war than Schutte-Lanz’s 

    rigids or Parseval’s non-rigids.

    N.B. The primary difference between Basenach’s approach and the

    frequently used “belly moor” was that the pivot point was directly

    connected to a low point of the hard structure. His claims do not indicate 

    that the ground-anchor, the mating point on the landing field, could be

    part of a movable structure.

  • 12 Oct 2013 9:03 AM | Deleted user

    Todays patent was Liebert’s seventh LTA patent.

    It was assigned to the Wingfoot Corporation of Akron.

    The Wingfoot Corporation was a subsidiary of Goodyear, 

    apparently formed in the late ‘30s and active throughout 

    World War II. Perhaps one of our members might be able 

    to shed a little light on the company and its purpose.

          “This invention relates to the construction of airships and 

    especially non-rigid airships, which are operated at internal 

    pressure by means of air bags, and has particular reference 

    to the improvement of the air system for controlling the internal 

    pressure of such airships.

          One object of this invention is to reduce the air resistance 

    due to projecting air scoops in previous constructions.

          Another object of this invention is to control the pressure on 

    the discharge side of the air safety valves which discharge air 

    from the ballonets, also applicable for gas safety valves.”

    NOTE: Figures 1 & 2 show two ballonets connected to Liebert’s

    non-collapsible air duct. Sixteen of the seventeen claims refer to a 

    pressure airship with at least one air ballonetClaim 3 doesn’t 

    mention ballonets, but explains that one of the airship’s streamlined

    struts has a frontal opening that serves as the air source for maintaining 

    envelope pressure. N.B. Nothing in the claims indicate multiple 

    ballonets either to trim the ship, or cool the lifting gas).

    The patent is cited by ten patents:

     2,929,581  Airship-enclosed radar unit

     4,076,188  Blower and burner to produce superpressure in a 

                       thermal airship

     5,333,817  Ballonet system for a lighter-than-air vehicle

     5,538,203  Ballonet system for a lighter-than-air vehicle

     6,607,163  Autonomous stratospheric airship

     8,459,589  External pressurization system for lighter than air vehicles

     CN101157383B A novel V-shaped solerairship

     DE102010020472 Externes Druckbeaufschlagungssystem für 


     EP1156960 Autonomous stratospheric airship

     WO1995014607 A ballonet system for a lighter-than-air vehicle

  • 11 Oct 2013 9:30 AM | Deleted user

    Todays patent is the second of Liebert’s eight U.S. Patents.

    It was Fischer's only patent.

    All eight were assigned to Goodyear-Zeppelin or the Wingfoot Corp.

    Beware of the OCR rendition supplied by google/com:   

      Another object of our invention is to provide a novel arrangement 

    and structure of the ballast water recovering apparatus which provides 

    a number of improved features over the apparatus heretofore known. 

    The structure embodying our invention is composed of two 

    principal operating parts, a pre-cooler and a condenser.”

    The correct text, starting with line 24:

          "Another object of our invention is to provide a novel 

    arrangement and structure of the ballast water recovering apparatus

    which is supported entirely by a main ring of the airship and which is 

    provided with a mechanism whereby the exhaust gases are partially

    cleansed before they are condensed.

          Heretofore, ballast water recoverers have been employed in 

    conjunction with internal combustion engines of airships in which air 

    has been utilized to cool the exhaust gases from the engines. Our invention 

    is directed to a ballast water recoverer of this type, which is peculiarly

    adapted to be installed in airships of the rigid type. Our invention provides 

    a number of improved features over the apparatus heretofore known. 

    The structure embodying our invention is composed of two

    principal operating parts, a pre-cooler and a condenser.”

    NOTE: Unfortunately, their patent is directed exclusively at a recovery 

    system which is incorporated in the outer skin of a rigid airship. This 

    may partially explain why the patent is cited by only one modern 


    4,813,632 "Ballast management system for lighter than air craft".

         The inventors emphasize the adaptability of their pre-cooler,

    separator, and condenser sections which permit operation under 

    various climatic conditions. They also emphasize that the condensate

    tank serves only as a temporary storage device. 

    The zeppelins crew will be responsible for transferring the water to the

    various ballast tanks (or dumping it overboard) to maintain the ship's trim. 

    N.B. They do not indicate any attempt to control or limit the temperature

    of the ballast water which their device collects.

  • 10 Oct 2013 10:14 AM | Deleted user

    Todays patent is Desmarteau’s only U.S. patent related to airships.

          “Airships of known type generally use a lighter than air 

    gas for sustentating the same.These gases are generally expensive 

    and often dangerous. Moreover, most airships built to date had 

    rigid structures which necessitated accurate adjustment of the

    different constituting elements, which were expensive to 

    manufacture compared to their dimensions and their bearing 

    capacity, and were vulnerable to collisions and were affected 

    by hurricanes and other atmospheric turbulences.

          The general object of the present invention resides in the 

    provision of a dirigible, or airship, which obviates the

    disadvantages mentioned hereinabove and which constitutes 

    an important improvement in the building technique of dirigibles.

          A more specific object of the present invention resides in the 

    provision of a dirigible, or airship, which is inflated and air-borne 

    by hot gases produced by the propulsion means.”

    NOTE: Desmarteau’s patent depends upon the discovery and production 

    of dramatically advanced materials. Starting on column 4, line 69:

    “For example, the airship in accordance with the invention can 

    have a length of 2400 feet with, a maximum diameter of 700 feet 

    and (be) capable of travelling at 300 miles per hour with a turbojet 

    engine developing 5000 HP. The gas temperature in the annular 

    zone can be maintained at about 700 degrees Fahrenheit. A large 

    number of passengers or a great amount of merchandise can be 

    carried in (the) nacelle. The airship can be provided with winch

    means to serve as a load-lifting device.  During an extended stop,

    the turbojet engine can be used as a fan by driving the same by

    means of its starting electric motor in order to maintain the desired

    pressure inside zone.

    Don’t know how many hours would be required to safely bring the 

    machine from ambient to desired operating temperature, or many 

    thermal cycles such a machine might survive(even if it never sucked

    in rain or snow)

    Elsewhere the patent mentions that some confined gases will be at 

    temperatures up to 2000 degrees F.

    N.B. Heated air is the only lifting gas mentioned. Neither claims nor 

    text identify any directional controls other than the steering exhaust. 

    You can link to all eighteen patents which reference this patent on www.google.com/patents.

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