Browse Topic: Airships

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The Dirigible Helicopter: Korean-American Inventor Young Ho Koun's Ambitious Attempt to Make Aircraft Survivable in the Event of Loss of ControlF-0080-2024-11235/7/2024
Revealed in 1941, the Dirigible Helicopter or 'Koun's Craft,' was an ambitious but ill-fated fusion of convertiplane and lighter-than-air technology. This S/VTOL (Short/Vertical Take Off and Landing) concept (a veritable puzzle of diverse airplane parts) was powered by a single, tilting propeller engine and was affixed with wing mounted, helium filled enclosures for additional buoyancy. Dismissed historically as being an eccentric folly of its layman inventor, Korean-American Young Ha Koun, the development of the Dirigible Helicopter has never been thoroughly studied. This paper will examine the origins of this unique design, its creator's possible motivations for building such an aircraft, and successor convertiplane concepts that attempt to achieve the same purpose to this day.
Cowels, C. Sundiata
Tools for the Conceptual Design of a Stratospheric Hybrid Platform2020-01-00253/10/2020
CIRA is currently designing a HAPS for Earth Observation and Telecommunications named High Altitude Hybrid Airship. The configurations considered, can generate both aerodynamic and aerostatic forces to balance the weight during the different phases of a mission. The design of a hybrid configuration for stratospheric platforms represents a novelty in itself in the aerospace sector while some hybrid platforms have been proposed only for tropospheric applications. In order to carry out the conceptual design, some design tools have been implemented to rapidly obtain a conceptual layout, which can be used to perform CFD, FEM and stability analysis and, at the same time, to compute the relative platform mass breakdown. The proposed conceptual design process is based on two steps. A first coarse exploration algorithm which, starting from some input parameters, determines the best buoyancy ratio and some overall platform parameters (among others: weight, volume and dimensions) using some semi-empirical formulas to define sub-systems masses, aerodynamic coefficients and structures sizing. The second step consists in a finer optimization around the geometry obtained at the previous step, based on a better definition of the layout, which provides, as final output, a 3-D CAD layout of the stratospheric platform and its main structural elements. Layout modification during the design conceptual process represents an innovative aspect, which allows improvements, since the beginning of the design, the results. This layout, finally, represents the input for CFD, flight stability and FEM analysis. In this paper, this innovative conceptual design process defined to obtain some conceptual configurations of a hybrid HAPS, and the implemented design tools will be described. Furthermore, some HAPS layouts and preliminary CFD analysis will be presented.
Baraniello, Vincenzo Rosario, Persechino, Giuseppe, Borsa, Roberto
High Altitude Platform System Airship for Telecommunication and Border Monitoring Design and Physical Model2020-01-00443/10/2020
This paper presents an accurate analysis of an innovative high altitude platform with an unconventional ellipsoidal shape during the most critical operation. The airship is designed accordingly to the specifications, which have been analyzed in terms of the required CONOPS (Concepts of Operations) which are associated with the proposed High Altitude Pseudo-Satellite (HAPS) technology and special operations and to analyze the operational scenarios. An innovative cruiser feeder system is defined and studied. The CONOPS includes communications relays, support of intelligence, surveillance, target acquisition monitor “mobile targets”, and reconnaissance, including long-range ISTAR missions performed by the feeder, combining satellite vision and HAPS vision for a forest fire, disasters, naval accidents, maritime and ground borders. The paper realizes a multidisciplinary analysis that allows creating the design of the HAPS, referring to both cruiser and feeder in different operative scenarios. It is expected to produce the preliminary basis for a future digital twin based design to generate the best possible configuration by mean of implementing multiphysics simulations. Structured object-oriented design processes involve developing several different system models and configurations. The modular design of the core modules is necessary for both ensuring the adequate performances, the capability of satisfying the operative necessities which have been defined by the CONOPS and fulfilling the requirements.
Trancossi, Michele
Ludwig, Rudolf and Emil Rüb: Forgotten German Aeronautical and Rotating-Wing PioneersF-0075-2019-146175/13/2019
Ludwig Rudolf Rüb, a passionate inventor, lived in poverty most of his life and is virtually unknown in the rotorcraft community. His inventions covered combustion engines and motorcycles first. Around 1900 he built a paddle-wheel plane under contract by Count Zeppelin, next he designed and built a first version of a coaxial rotor helicopter in Munich, and then he moved to Augsburg for building a large fixed-wing aircraft. None of these were ever finished. At the begin of WW I, with support of the German army, he took up a refined version of his coaxial rotor helicopter concept as a highly agile and maneuverable replacement of the observation balloons used in those times, which also was intended to take an active part in warfare by installing a machine gun or dropping bombs. It included some astonishing advanced features and with the help of his sons the construction was finished; ground testing started in June 1918. The end of the war immediately stopped all works; the contract of Versailles demanded the destruction of that vehicle and thus formed the end of the Rüb aeronautical work. Ludwig Rüb died 1918, after months of illness, without having seen the rotors turning.
G., Berend
Safety Analysis of an Airship Which Loses Lifting Gas from the Hull2018-01-195410/30/2018
This study investigates the physical phenomena that affect a high-altitude airship in the presence of lifting gas losses from the hull. General atmospheric thermodynamics and basic physical principles are adopted to describe the behavior of an airship with envelope failures that generate buoyant gas dispersion or depressurisation phenomena. Overpressure that could grant to maintain some controllability during a large part of the descent is assessed by mean of the thermodynamic model of the envelope in the presence of gas losses. Optimisation of the inflation parameters is provided and the conditions for avoiding dangerous crashes on the ground and the potential recovery of a damaged vehicle, people and its payload. In particular, the requirements for a slow depressurisation is computed by the equilibrium with the atmosphere and then how can it be possible to sustain controlled navigation are determined. A key factor for security relates directly to the capability of preserving some airship balloon overpressure for the longest time possible. This condition can extend much the range of control. Complete forfeit conditions will be determined to demonstrate that airship cannot be anymore controllable below 20% of the initial altitude at which the failure has started. In some cases, specific manoeuvres could allow configuring the deflated balloon as a parachute, if coupled with adequate safety systems. This research about safety conditions will also be useful for designing safety systems. A general guideline for safety systems has been defined showing that airship if well created and well governed in emergency conditions will be much safer than any other aerial vehicle.
Trancossi, Michele, Pascoa, Jose, Cannistraro, Giuseppe
Aerodynamically Stabilized Instrument PlatformTBMG-2600512/1/2016
The AeroPod, developed at NASA Goddard Space Flight Center’s Wallops Flight Facility, is a passive device that uses aerodynamic forces to stabilize an instrument package suspended from a kite or tethered blimp. The AeroPod’s design for steadying and damping payloads includes the use of a tail boom and fin combination. It is a novel design and provides a relatively simple alternative to the traditional methods for suspending equipment from kites or blimps. It is a low-altitude custom remote sensing platform craft designed for, but not limited to, agricultural and environmental research purposes. AeroPods can be used for a variety of remote sensing and in-situ observations.
Image Processing Based Air Vehicles Classification for UAV Sense and Avoid Systems2015-01-24719/15/2015
The maturity reached in the development of Unmanned Air Vehicles (UAVs) systems is making them more and more attractive for a vast number of civil missions. Clearly, the introduction of UAVs in the civil airspace requiring practical and effective regulation is one of the most critical issues being currently discussed. As several civil air authorities report in their regulations “Sense and Avoid” or “Detect and Avoid” capabilities are critical to the successful integration of UAV into the civil airspace. One possible approach to achieve this capability, specifically for operations beyond the Line-of-Sight, would be to equip air vehicles with a vision-based system using cameras to monitor the surrounding air space and to classify other air vehicles flying in close proximity. This paper presents an image-based application for the supervised classification of air vehicles. First, several vehicle images, taken from different points of view, are transformed using a descriptor of salient features as to build the five-class database used to train the classification algorithm. Then, the latter compares the descriptor of a vehicle image taken from a random point of view to records in the database. With a positive match, the vehicle will be assigned to one of the following classes: a) civil transport aircrafts, b) military aircrafts, c) general aviation aircrafts, d) helicopters, and e) airships/hot air balloons. The paper provides a possible layout for the algorithm implementation and presents the outcome of several tests performed to evaluate its efficiency and possible exploitation. Indications useful to further studies are presented to help future researches.
Ceruti, Alessandro, Curatolo, Simone, Bevilacqua, Alessandro, Marzocca, Piergiovanni
Synthesis of Time Quasi-Optimal Asymptotically Stable Control Laws2015-01-24819/15/2015
The solution of the both synthesis and implementation problems of high-rapid rates control laws is extremely important for the development of automatic control systems of the aircraft. This is due to the high speed of such vehicles. Along with this, it is imperative that control laws provide that system is asymptotically stable, as the basis for the reliability of their controlled motion. Another important objective of the method of synthesis of control laws for aircraft is compulsory compliance with strict limitations on the values of control inputs at the actuation devices. It is equally important that the control laws provides limitations on the state variables of aircraft, such as velocity, acceleration, etc. Pontryagin's maximum principle is aimed at solving such a time-optimal problem with the limited command variable. However, both the mathematical formalism of this principle, and the mathematical formalism of the methods based on this principle don't provide a solution of the class described tasks. The problem is that, despite the fundamental theoretical validity of these methods, they don't provide robustness synthesized control laws. Robustness is understood here as the insensitivity of the properties of the control system to small variations in the properties of the control object. The reasons for this phenomenon are known. They are as follows: the asymptotic properties absent in positional control, maximum speed law is defined only within a given time interval, the stabilizing feedback is absent. As a result the inadequacy of the dynamic properties of a managed object and calculated data can lead to a complete loss of the control system quality. The essence of the proposed approach consists in influencing the change of the derivatives of the state variables, which form a system of phase coordinates. Each derivative of the state variable is formed by a special non-linear law. These laws impose a number of requirements: the derivative of the phase coordinates is limited, its rate of change is close to optimal for the designated limit, the law of its change is asymptotically stable. In other words, the state-space of the control object form specific invariant manifolds. These manifolds are formed by specially synthesized control law so that their properties are determined by the above requirements. Mathematically varieties are generated by nonlinear functions of the right sides of the system of differential equations of state of the control object. Structures and function parameters form the mathematical model of the control law. The resulting control action (signal input) sequentially generates the processes of change of phase coordinates in such a way that directs the state variables of the system on the given invariant manifolds. Formed diversity determine the dynamics of the controlled system. They in aggregate form its attractor, which meets the following properties: near-optimal performance, bounded of phase coordinates and asymptotic movement. The procedure of successive synthesis of invariant manifolds is given can be implemented for objects that have a mathematical model in the form of the Cauchy problem with the so-called “triangular” structure. For such a model is a characteristic that every i-th state variable of the system, which has the order of “n” and “r” of the control inputs, depends only on the state variables with index not greater than i + 1. In this case, any derivative of the state variable may depend on only one control input, and the n-th derivative is necessarily dependent on one of these inputs. This result is very important for the practical problems of management of working bodies of aircraft. For them, the control speed is a critical factor in the quality of flight and stability and robustness is a critical factor in the reliability of automatic control. Application of the proposed method is illustrated by the example of the construction and study of the automatic control system of the device controlling airship.
Neydorf, Rudolf
New Unconventional Airship Concept by Morphing the Lenticular Shape2015-01-25779/15/2015
The aim of this paper is to develop a new concept of unconventional airship based on morphing a lenticular shape while preserving the volumetric dimension. Lenticular shape is known to have relatively poor aerodynamic characteristics. It is also well known to have poor static and dynamic stability after the certain critical speed. The new shape presented in this paper is obtained by extending one and reducing the other direction of the original lenticular shape. The volume is kept constant through the morphing process. To improve the airship performance, four steps of morphing, starting from the lenticular shape, were obtained and compared in terms of aerodynamic characteristics, including drag, lift and pitching moment, and stability characteristics for two different operational scenarios. The comparison of the stability was carried out based on necessary deflection angle of the part of tail surface. The comparison results indicated that new shape concept possesses much better aerodynamic and stability characteristics and could be used for detailed optimisation studies.
Ceruti, Alessandro, Marzocca, Piergiovanni, Voloshin, Vitaly
Airship and Hot Air Balloon Real Time Envelope Shape Prediction through a Cloth Simulation Technique2015-01-25789/15/2015
The flight simulation of airships and hot air balloons usually considers the envelope geometry as a fixed shape, whose volume is eventually reduced by ballonets. However, the dynamic pressure or helium leaks in airships, and the release of air to allow descent in hot air balloons can significantly change the shape of the envelope leading to potential dangerous situations. In fact, in case of semi-rigid and non-rigid airships a reduction in envelope internal pressure can reduce the envelope bending stiffness leading to the loss of the typical axial-symmetric shape. For hot air balloons thing goes even worse since the lost of internal pressure can lead to the collapsing of the balloon shape to a sort of vertically stretched geometry (similar to a torch) which is not able to sustain the attached basket and its payload. These effect should be considered in simulations, however to compute in real time the envelope shape with Finite Element Methods is a complex and demanding task due to the high deformations, complex fabric model, and wrinkling effects. A possible solution to overcome this problem is to apply a Cloth Simulation Technique (CST) to the prediction of the envelope behaviour. This paper describes how such a model can be implemented for airship envelops and hot air balloons shape predictions. Appropriate algorithms have been developed in Matlab® and validation test have been conducted. Results show that this model can provide qualitatively good results, in agreement with the experience and the physics of the problem.
Ceruti, Alessandro, Marzocca, Piergiovanni
Spy Blimps Revisited: A Performance Comparison between Two Competing Approaches2015-01-25799/15/2015
While operational airships globally number in the low dozens, interest in buoyant or semi-buoyant platforms continues to arouse imaginations of commercial and military planners and developers alike. The airship-as-advertisement business model is the only model that has proven sustainable on any scale since the crash of the initially successful LZ-128 Hindenburg effectively ended regular passenger and cargo transport by airship, and the 1962 termination of the US Naval airship program terminated regular large-scale surveillance from airships. Efforts in the US and Japan during the 2000's to have a self-sustaining sight-seeing business model using the modern semi-rigid Zeppelin NT both failed. In theory, the buoyant nature of airships provides compelling endurance and cost-per-ton-mile capability which fills a niche arguably not currently occupied by other modes of transportation. The potential endurance capability motivated the US Military to fund two nearly-simultaneous airship surveillance programs in 2010. Having similar missions, the primary differentiator between the two programs had to do with choice of basic hull form. The Army's Long endurance Multi-Intelligence vehicle was to be a lifting-body semi-buoyant “hybrid” vehicle. The Air Force's Blue Devil Block 2 was to be a conventional ellipsoidal airship. The author's pre-contract-award 2010 paper compared the loitering performance of the two platforms using a basic mission simulation, giving the nod to the conventional ship. This study revisits the basic assumptions of the simulation in view of new publicly available aerodynamic information, and revises the results, finding the hybrid to be the superior option.
Buerge, Brandon Todd
Identification of Traction and Power Characteristics of Air-Screw Propulsors in Mathematical Description of Airship2014-01-21349/16/2014
The paper formulated and solved the problem of investigating the traction and power characteristics of air-screw propulsor for airships. The study is performed by constructing a mathematical model relating the steady-state values of the shaft power and traction on the axis of the screw with the velocity of rotation and the actual velocity of the aircraft. Proved design scheme selection of computer simulation of aero-and thermodynamic processes occurring during rotation of the airscrew. Describes plan developed under the experimental task, providing variation in the basic parameters of the airscrew, motion parameters and flight environment The results of computer modeling of the interaction of the airflow with the airscrew at various combinations of these parameters. Results are shown in tabular and graphical form and as a mathematical model of the studied airscrew. Importantly, by developed and tested the method can construct mathematical models of airscrew propulsors any specific structures and geometrical parameters. This result is extremely important and useful for solving problems related to the selection, design and optimization of airscrew propulsors of airships and other aircraft with airscrew propulsors. These results are important for the development of motion control systems aircraft.
Neydorf, Rudolf, Sigida, Youriy
Method of Docking for Stratospheric Airships of Multibody Transportation System2014-01-21629/16/2014
The paper describes methods for control of docking of two moving stratospheric airships. One of them (cruiser) implements cruising flight at the defined altitude with defined velocity. The other one (feeder) fulfills the mission of chasing the cruiser with following docking operations. Mathematical model of exact airships are used in the work. Instances of structural and algorithmic implementation are based on position-trajectory controller. Simulation of docking control was accomplished with proposed methods.
Pshikhopov, Viacheslav, Medvedev, Mikhail, Krukhmalev, Victor, Fedorenko, Roman, Gurenko, Boris
Airship Positioning Fuzzy Multi-Ballonet Control Study2014-01-21469/16/2014
Airship designers research application versions of systems with several ballonets for adjustment of airship roll and/or pitch as a whole. This requires effective automatic status management of each separate ballonet. But multi-ballonet system control issue encounters the absence of industrially measurable variables of each separate ballonet status. Thus status control issue of the system becomes uncertain. The fact requires the issue studying and shaping new scientific and technical solutions. This publication represents research results implying that fairly simple implementation and effective result can be achieved by application of fuzzy control concept. Its application is built on generating the representative quantity of fuzzy production rules. They are based on present set evaluation of known parameters and measured variables. This results in fuzzy but meaningful image of ballonet system status and airship as a whole. Thus achieving fairly good control over multi-ballonet system. This article represents development results of fuzzy automatic control system version of two-ballonet system containing determined positional control systems of pressure difference between body gas environment and atmosphere. The resulted hybrid control system maintains necessary pressure in airship body and provides airship trim control efficiency at low traveling speed. Modes like that appear during take-off and landing. The development is based upon airship model with ballonet control system which adequacy has been checked by previous researches. This model was used to research and experimentally correct conditions and influence results of developed production rules on ballonet system status and airship as a whole. Control law fuzzy derivation procedure is demonstrated and explained. Described is simulation modeling diagram of fuzzy control hybrid system of two-ballonet system in Simulink environment and its computer testing results. Illustrated is airship positioning fuzzy control maintaining boost pressure in body to provide its specified rigidity.
Neydorf, Rudolf, Novikov, Sergey, Kudinov, Nikita
Aerostatic Aircraft Flight Environment Modeling and Investigation2014-01-21479/16/2014
Airship dimensions define the application of the computer modeling methods under their development and investigation. Herein, the need to simulate the flight environment state - the atmospheric conditions of their traffic route - arises. The atmospheric parameters have both regular and random components, which is due to the nonstationarity of the atmospheric phenomena. Hence, it is essential to define the actual ranges, and the representative values of the atmospheric effects. Weather data are used for the analysis and the airflow performance computation in the operational area. Through their statistical processing, we need to obtain the most informative characteristics of the weather conditions in whole, and of their trends. The investigation has shown that the weather data gathering system is nonperfect. The sampling frequency is irregular and not high, test values in the specific parameters are obtained asynchronously. At this, altitude is the most critical parameter under measuring, and all the observable parameters are to be referenced to the altitude in the problem on the flight environment parameter simulation. Consequently, the problem on the statistical processing of the weather data array acquires importance and specificity. Efficient algorithms of the Integrated Global Radiosonde Archive application are considered in the paper. It is shown how the most informative estimates of the route time and calendar conditions affecting the flight aerodynamics can be obtained on the base of the data statistical processing. The research and calculation algorithm is based on the fact that all the controlled parameters are to be referenced to the altitude. Thus, the problem on the data statistical processing acquires clear directionality from the preprocessing and efficient data structuring up to the objective estimation of their processing results.
Neydorf, Rudolf, Sigida, Youriy, Kudinov, Nikita, Portnova, Elena
Roto-Cycloid Propelled Airship Dimensioning and Energetic Equilibrium2014-01-21079/16/2014
Rotocycloid propulsion presents interesting performance as a possible long-term alternative to helicopters in a far future. It will lead to increase the energy efficiency of VTOL vehicles. This paper focuses on optimization of an airship with the possibility up to 2000 h/year of photovoltaic propelled flight at a cruise speed about 20 m/s. This paper demonstrates the feasibility of this airship concept and presents a full dimensioning according to the CDE (Constructal Design for Efficiency) developed at University of Modena and Reggio Emilia. The proposed solution has been deeply analyzed and the analysis of performances has been presented. The results allow thinking to a novel class of vehicles designed specifically to take the maximum advantage by this propulsion method.
Trancossi, Michele, Dumas, Antonio, Xisto, Carlos, Pascoa, Jose, Andrisani, Andrea
MAAT Cruiser/Feeder Airship: Connection and Passenger Exchange Modes2013-01-21139/17/2013
In the general framework of the EU FP7 MAAT project, a novel green air transport architecture is under development. The paper presents the possible architectures for the cabin connections and the transfer modalities for people, crew and freight, for to the European project MAAT. Different architectures have been evaluated setting out to cover the structural and propulsive needs and to enable the transport modes between the Cruiser and the Feeders. The different possibilities are discussed conceptually, by considering the advantages and disadvantages of the presented configurations. The bases for future detailed design and research are established, as through such conceptual study the main parameters are identified and found to affect the general design of both airships and their operability. The aim of this paper is to specify the necessary elements, which are necessary to perform the docking operation by taking into account the prescribed Feeder-Cruiser geometries. Consequently, it provides the guidelines for the initial validation of the feasibility to apply the proposed Cruiser- Feeder shapes. It is expected that the results will be applied to the new generation of airships design by allowing the definition of the future Cruiser/Feeder based aerial transport.
Vucinic, Dean, Sunol, Anna, Trancossi, Michele, Dumas, Antonio, Gaviraghi, Giorgio
A Predictive Climatic Model for Ballast in a Fixed Volume Blimp2013-01-22049/17/2013
This paper presents a mathematical model of the vertical forces acting on an airship during vertical motion. The main effort is the definition of an airship model, which move only vertically by ballast, and buoyancy effects, with a much reduced energy consumption for take-off and landing operations. It has been considered a disc-shaped airship, which can operate using the open balloon airship architecture defined to operate safely with hydrogen. This architecture does not require internal ballonets, because of the connected increased fire dangers that they create even if vented. Several models of airship based on vertical forces have been presented in literature. They often consider only the US or International Standard Atmosphere models and they neglect effects of weather conditions. The latter are connected with the location and with the season. These environmental and climatic factors have a large influence on behaviors of the airship system, because it is well known that the internal buoyant gas changes pressure and density condition because of external temperature. This paper defines the lifting behavior in terms of speed and acceleration. It evaluates the load factor as a function of the buoyancy and the ballast on board as a function of climatic conditions. A very simple methodology has been also presented on daily basis, authors neglect the effect of overheating of the gas due to solar radiation on the surface of the balloon, which can support the predefinition of climatic effects. The proposed methodology corrects the International Standard Atmosphere model by considering climatic data such as temperature, density and pressure of the air dependent on seasonal factors and location on annual basis.
Dumas, Antonio, Madonia, Mauro, Trancossi, Michele
Stability Analysis of the MAAT Feeder Airship During Ascent and Descent with Wind Disturbances2013-01-21119/17/2013
This paper looks into with the aerodynamic properties and stability of the feeder airship in the framework of MAAT project. FP7 MAAT project is based on the concept of two different types of airships (the cruiser and the feeder) working together as a transportation system. The feeder considered in this paper is a rigid airship with an unconventional envelope shape. Aerodynamic forces and moments acting on the airship during the horizontal and vertical flight modes are of special interest in this study, because the aerodynamic performance of the aircraft directly influences its general dynamic behavior and, thus, its in-flight stability. A set of CFD simulations was conducted for vertical and horizontal flights of the feeder airship. Drag and lift forces and pitching moment together with their coefficients, were obtained for different altitudes and velocities from the proposed operational ranges of the airship. Based on the results of CFD simulations the relations between these aerodynamic coefficients and flight parameters were established. For the dynamic modeling purposes, the feeder airship was assumed to be a rigid body. The stability analysis was carried out in frames of the obtained results. The mathematical model of the feeder airship dynamics, was developed using the classic rigid body dynamic approach and the established coefficients relationships. The authors identified the range of the angles of attack for which the airship remains statically stable.
Neydorf, Rudolf, Sigida, Youriy, Voloshin, Vitaly, Chen, Yong
Aerodynamic Characteristics Study and Possible Improvements of MAAT Feeder Airships2013-01-21129/17/2013
This paper is dedicated to the study and improvement of the aerodynamic properties of the feeder airship in the context of MAAT project. FP7 MAAT project is based on the concept of two different types of airships (the cruiser and the feeder) working together as a transportation system. The current feeder concept includes unconventional shape changing envelope. Two problems are considered in this paper. The first problem is to find a condition of the effective vertical ascent for the feeder (from the ground to the altitude of the cruiser). A series of CFD simulations were carried out for the top flow for a range of altitudes from 0 to 16 km and velocities between 2 and 10 m/s. The results confirm the appearance of some negative effects, including high drag during the vertical ascent, especially, at low altitudes. The second problem is to study and reduce the side wind effects on the ascending feeder airship. Another series of CFD simulations was conducted for the side flow at the same altitudes as in the first problem and for the velocities between 10 and 50 m/s. The results show the occurrence of the effect of downforce wing (negative lift) on the altitudes of 10‑14 km. The authors have provide suggestions for the shape variations in order to reduce high drag during vertical ascent and negative lift effect caused by side wind.
Voloshin, Vitaly, Chen, Yong, Neydorf, Rudolf, Boldyreva, Anna
Optimization of Airships with Constructal Design for Efficiency Method2013-01-21689/17/2013
It is possible to define a novel optimization method, which aims to overcome the traditional Multidisciplinary Design Optimization. It aims to improve Constructal design method to optimize complex systems such as vehicles. The proposed method is based on the constructal principle and it is articulated in different stages: 1 preliminary top-down design process to ensure that the full system has one of the best configurations for the specified goals (contour conditions for constructal optimization could be stated ensuring an effective optimization at full-system level). 2 constructal optimization of the elemental components of the system to maximize the system performances; 3 eventually a competitive comparison between different configurations choosing the better one. The definition of an optimized flying vehicle (an airship) has been produced an example of this improved design method with the objective of minimizing the energy consumption during flight. Following this method, this paper aims defining the guidelines for an effective energetic optimization of an airship. The produced results allow defining a novel airship concept, which optimizes the airship shape to reach three fundamental energetic goals: energy consumption minimization, photovoltaic energy production maximization, definition of the conditions for energetically self-sufficient flight. This paper also demonstrates that the resulting architecture can fit perfectly novel operating conditions such as effective point to point logistic without any airport infrastructure having a potential breakthrough impact on the aerial logistic models and allowing an effective and better integration with any other terrestrial, maritime and aerial transport mode.
Trancossi, Michele, Dumas, Antonio, Madonia, Mauro
High Altitude Transitional Flow Computation for a Propulsion System Nacelle of MAAT Airship2013-01-22689/17/2013
The flow around the nacelles of high altitude airships is very important in order to assess the inlet conditions and losses associated to their propulsion systems. The aerodynamics prediction of low Re number flows is a problem usually associated to the lack of accuracy of most of the turbulence models in everyday use. Herein we present a laminar kinetic energy transitional model that is then applied on the analysis of the flow around an example of the MAAT airship nacelle. The model is also validated using several well known test cases from the literature. Results indicate the effects of accurate transition prediction in the redesign of the nacelle for improvement in efficiency.
Vizinho, Rui, Pascoa, Jose C., Silvestre, Miguel
Continuous-Positional Automatic Ballonet Control System for Airship2013-01-22369/17/2013
This paper is devoted to a method of creating of the automated ballonet system for pressure control inside an airship envelope. Along with the study of the effects of the positional control system parameters, the authors develop novel control scheme. It is based on a new hybrid controller, which combines positional approach to forming the output control signal with a contour of continuous correction of input signal, which defines the pressure drop on the surface of the envelope as a function of the flight altitude. This approach allows reducing the effect of self-oscillations of airship envelope internal pressure on the flight altitude. In order to prove the new approach the mathematical model is being obtained. The results of the derivation and simulations of the control system operation are presented in this paper.
Neydorf, Rudolf, Novikov, Sergey, Fedorenko, Roman
Propulsion of Photovoltaic Cruiser-Feeder Airships Dimensioning by Constructal Design for Efficiency Method2013-01-23039/17/2013
The European project MAAT (Multi-body Advanced Airship for Transport) is producing the design of a transportation system for transport of people and goods, based on the cruiser feeder concept. This project defined novel airship concepts capable of handling safer than in the past hydrogen as a buoyant gas. In particular, it has explored novel variable shape airship concepts, which presents also intrinsic energetic advantages. It has recently conduced to the definition of an innovative design method based on the constructal principle, which applies to large transport vehicles and allows performing an effective energetic optimization and an effective optimization for the specific mission. While the traditional constructal method performs an optimization with a down-to-top approach, it produces an optimization process in two stages: the first one defines the optimal characteristics of the system understood as a unitary system to achieve the desired performances; the second analyzes the subsystems, examining those most disadvantaged, in order to optimize its performance for the desired goal. It has been deeply tested on a traditional shaped airship allowing verifying that a changing volume airship has globally better energetic performances than a fixed volume one. This paper performs a preliminary analysis of the method for the design of a cruiser/feeder multibody airship such as the one, which is going to be designed inside the MAAT project. The model presented defines the guidelines for the optimization of the system considering the magnitudes involved in flight physics to achieve the goal of energetic self-sufficiency.
Dumas, Antonio, Madonia, Mauro, Trancossi, Michele, Vucinic, Dean
Motion-Corrected 3D Sonic Anemometer for Tethersondes and Other Moving PlatformsTBMG-1509611/1/2012
To date, it has not been possible to apply 3D sonic anemometers on tethersondes or similar atmospheric research platforms due to the motion of the supporting platform. A tethersonde module including both a 3D sonic anemometer and associated motion correction sensors has been developed, enabling motion-corrected 3D winds to be measured from a moving platform such as a tethersonde.
Energetic Design and Optimization of a Large Photovoltaic Stratospheric Unconventional Feeder Airship2012-01-216610/22/2012
This paper presents a model of energetic consumption and photovoltaic production for a large airship which acts as feeder connecting the ground with a large cruiser. The analysis of energy needs and productivity allows defining both an ideal sizing and operative mission profiles. The specialised mission of this airship is to ascent and descent. It includes also the connection with the airport buildings on the ground and with the cruiser at high altitude. Photovoltaic production has evaluated in terms of hydrogen and electric propulsion. They have estimated both and a calculation methodology has proposed. The evaluation has supported by CFD evaluations on aerodynamic behaviour of the system at various altitudes.
Dumas, Antonio, Trancossi, Michele, Madonia, Mauro
Quite-Rigid Airship Structure Concept and Design for Enhanced Hovering Capability2012-01-18929/10/2012
This paper explores a novel structural design concept for a demonstrator of a high altitude photovoltaic feeder airship. The presented structural design concept aims to minimize the use of strategic materials in the structure of the airship, but also to maximize the ease of construction of the structure. The proposed design concept and method an effective analysis of historic airship structures considering their efficiency vs. weight and desired performances. By this analysis a novel structural design has been defined to reach the ambitious goal of a lighter and cheaper structure concept which can ensure comparable performances with traditional rigid airships. A discoid shaped airship with a central column has been taken into account. Structural calculations and constructive design has been presented in depth.
Madonia, Mauro, Trancossi, Michele, Coppola, Agostino
Fire-safe Airship System Design2012-01-15122/29/2012
This paper presents the new Hydrogen Fire-safe Airship system that overcomes the limitations present in previous airships designs of that kind, when considering their functioning at advanced operative position. Hydrogen is considered to be more effective than helium because of its low-cost production by hydrolysis, which process is nicely driven only by the photovoltaic energy. This paper presents a novel architectural concept of the buoyant balloon designed to increase the fire related safety, when applying hydrogen as the buoyant gas. The proposed buoyant volume is designed as a multi-balloon structure with a naturally ventilated shape, to ensure that hydrogen cannot reach the dangerous concentration level in the central airship balloon. This concept is expected to be the start of a novel hydrogen airship type, to be much safer than preceding ones. It permits to reduce the traditional economic costs, when compared with helium inflated airships, due to the helium scarcity in the world gas resources and its related production costs. This paper presents the volumetric analysis necessary for a preliminary design activity of this novel control system of the ballonets in this airship concept and to define the design of the airship's architecture.
Pascoa, Jose, Trancossi, Michele, Dumas, Antonio, Madonia, Mauro, Vucinic, Dean
Multibody Advanced Airship for Transport2011-01-278610/18/2011
The MAAT project (Multibody Advanced Airship for Transport) aims to investigate aerial transportation possibility by airship based cruiser-feeder system. MAAT is composed by two modules: The cruiser, named PTAH, (acronym of Photovoltaic Transport Aerial High altitude system); the feeder, named ATEN (Aerial Transport Elevator Network feeder), is a VTOL system (Vertical Take Off and Landing) which ensure the connection between the cruiser and the ground. They can lift up and down by the control of buoyancy force and displace horizontally to join to cruiser. The project aims to: 1 identify and design the most functional cruiser/feeder airship architecture based on a discoid innovative airship able to remain airborne for long periods and to travel great distances; 2 design the best type of propulsion both for cruiser and feeder so they can contribute together to the propulsion of an innovative modular airship; 3 minimize the environmental air transport impacts by annulling the fossil fuels energy consumption by designing both cruiser and feeder are energetically autonomous by photovoltaic energy and innovative electric propulsion. 4 study the different possible ways of approaching and joining between ATEN and PTAH, and consequently, the release of ATEN from PTAH. 5 design the best procedure of docking operations thus identified in order to obtain the minimum disruption to passengers and the maximum safety for themselves and for goods 6 study the different architectures of PTAH and Athens, in such a way that : a the lift up capacity guaranteed by the buoyancy force, may be accompanied by the power of the engines; b effective and safe procedures for docking; c ATEN can land and take off from Airport Hubs named AHA located in major populated centres d PTAH satisfies the better possible aerodynamic performances possible for the dimensions and the operative mission. To study the transfer operations between ATEN and PTAH of goods and people and vice versa, to: minimize distress conditions for passengers, maximize performances especially for goods; enhance safety of these operations to maximum possible level. The objectives described are congruent with each other and to achieve this study of the system and components must be highly structured…
Dumas, Antonio, Trancossi, Michele, Madonia, Mauro, Giuliani, Ilaria
In Situ Aerosol DetectorTBMG-104607/1/2011
An affordable technology designed to facilitate extensive global atmospheric aerosol measurements has been developed. This lightweight instrument is compatible with newly developed platforms such as tethered balloons, blimps, kites, and even disposable instruments such as dropsondes. This technology is based on detection of light scattered by aerosol particles where an optical layout is used to enhance the performance of the laboratory prototype instrument, which allows detection of smaller aerosol particles and improves the accuracy of aerosol particle size measurement.
Thermoelectric Energy Conversion Technology for High-Altitude AirshipsTBMG-91582/7/2011
The High Altitude Airship (HAA) has various application potential and mission scenarios that require onboard energy harvesting and power distribution systems. The power technology for HAA maneuverability and mission-oriented applications must come from its surroundings, e.g. solar power. The energy harvesting system considered for HAA is based on the advanced thermoelectric (ATE) materials being developed at NASA Langley Research Center.
Meet the Judges, "Create the Future" 2007 Design ContestTBMG-27394/1/2008
, P.E., Senior Principal Mechanical Engineer, Raytheon Integrated Defense Systems
Update on Controlling Herds of Cooperative RobotsTBMG-19476/1/2007
A document presents further information on the subject matter of “Controlling Herds of Cooperative Robots” (NPO-40723), NASA Tech Briefs, Vol. 30, No. 4 (April 2006), page 81. To recapitulate: A methodology for controlling a herd of cooperative and autonomous mobile robots exploring the surface of a remote planet or moon (specifically, Titan or Titan-like) is undergoing development. The proposed configuration of mobile robots consists of a blimp and a herd of surface sondes. The blimp is the leader of the herd, and it commands the other robots to move to locations on the surface or below the surface to conduct science operations. Once a target is chosen, the sondes cooperatively aim sensors at the target to maximize scientific return. This hierarchical and cooperative behavior is necessary in the face of such unpredictable factors as terrain obstacles and uncertainties in the model of the environment.
Inverse Rectennas for Two-Way Wireless Power TransmissionTBMG-21747/1/1998
The term "inverse rectenna" may seem like an oxymoron at first glance. However, preliminary experiments have demonstrated that a rectenna of suitable design can be made to operate in an inverse mode, in which radio-frequency (RF) power is generated in the rectenna rectifier circuits and radiated by the rectenna antenna elements.
An Acrobatic Airship ‘ACROSTAT’9119949/1/1991
A novel type of airships or a powered LTA aircraft has been proposed, which is designed with a rather conventionally shaped hull and with conventional thrusters and is not made as a control configured vehicle(CCV) nor utilized any sophisticated control mechanism. None of control surfaces are installed but couples of stabilizers equipped to the aft hull, and without any active control tricks the vehicle holds its stability and realizes enhanced maneuverability performances. This newly conceived type model is named as ‘ACROSTAT’. This airship can ascent and descent vertically, and can perform somersaults, spiral flights, and rotates around its C.G. as the center of the movement. The paper deals with the structural design concept of the model, design data and the attitude control principle.
Onda, Masahiko, Morikawa, Yasushi
Single Rotor Options for Heavy Lift and Potential of Multi Lift7910872/1/1979
After 30 years of continual rotor-craft payload capacity growth, there are strong indications that this trend is leveling off. First, this paper reviews the current state-of-the-art to show that the root of the problem is not any unsurmountable technical barrier and briefly discusses the single rotor options for heavier lift as illustrated by growth derivatives of the CH-53E as well as by the Sikorsky response to the Army HLH proposal. Secondly, it examines the economic factors which appear to have militated, up to this point, against development of larger helicopters for either civil or military requirements. Finally, the paper considers the opportunities to solve the problem of occasional requirements for very heavy lift of single piece payloads by the harnessing of two or more helicopters to a single load - the so called multi-lift concept. The history of Sikorsky studies and flight feasibility demonstrations are reviewed, and the opportunities for applying advanced control technology to offset the pilot workload problems identified in these demonstrations are discussed.
Carter, E. S., Cooper, D. E., Knapp, L. G.
Some Applications of Buoyancy Systems and Parawings to Replace Conventional and Proposed Transportation Systems7205802/1/1972
An exploratory study has been conducted to assess the performance potential of buoyant airships and parawings in short-haul passenger transportation. Results show that such systems can be used effectively, from a performance standpoint, in a VTOL or STOL mode of operation. A supplementary assessment of potential applications of such vehicles is examined, with a brief look at economic factors and an examination of missions for which they might be effectively used.
Havill, C. Dewey, Williams, Louis J.
WHAT AMERICA NEEDS IN A COMMERCIAL AIRSHIP - (The content of this report is based upon an undergraduate thesis prepared by Mr. Yachnin, Class of March, 1949)4900611/1/1949
Youngman, Clarence E., Yachnin, Stanley P.
The Airship and Its Place in Modern Transportation3701461/1/1937
THIS paper discusses the position of the airship as a means of transportation, briefly reviewing the history of the supposed but really non-existing competition between the airship and the airplane. The results of the Hindenburg's ten North Atlantic demonstration trips of 1936 are reported on, and the meteorological observations made are discussed. Figures of cost of operation and revenues of the Hindenburg are revealed, showing the relatively low cost of operation of the modern passenger airship. The relative places of the express steamer, the airship and the airplane in the future North Atlantic transport picture are discussed, and the necessity for cooperation between Germany and the United States in the future development of the airship is emphasized. Since Dr. Eckener presented this paper at the 1937 Annual Meeting of the Society, an increased 1937 schedule of Transatlantic service for the Hindenburg has been announced. Eighteen round trips across the North Atlantic, eight more than last year, are planned by the American Zeppelin Transport Corp., acting as U.S. agent for Deutsche Zeppelin Reederei, the operating company. The Naval Air Station at Lakehurst, N. J., will remain the American terminal.
Eckener, Hugo
AERIAL TRANSPORTATION AS A BUSINESS PROPOSITION2100141/1/1921
Aviation has no perfect analogy, for it has no precedent. Two classifications are made. Scheduled service includes the carrying of mail, express or passengers on a definite and regularly maintained schedule, independent of, or supplementary to, other forms of transportation. Special service includes pleasure flights, oil-field survey, selecting industrial land-sites, planning cities, aerial photography, forest-fire patrol, visiting remote points, exploration, aerial advertising, delivery of perishable products, real-estate survey and industrial purposes. Each of these classifications requires different equipment, organization and operating personnel. The equipment requirements and the reliability of aerial transportation are discussed, the necessity for suitable terminals and federal flying regulations are emphasized, the subject of insurance is commented upon and the development of aerial commercial transportation is outlined. Recent statistics regarding European air travel are quoted.
MARTIN, GLENN L
OPERATIONS OF NAVAL AIRCRAFT1900191/1/1919
THIS article, written shortly after the signing of the armistice, deals with the Naval aviation situation at the outbreak of war and its development during the war, ending with a brief discussion of the probable future lines of development. Figures are given showing the expansion occurring during the nineteen months of warfare, and the different ways in which the various types of aircraft were used. Future development is treated briefly, but that logical assumptions were made is indicated by the fact that the year which has elapsed since the article was written has shown a very decided trend along the lines indicated.
TOWERS, J H
NAVAL AIRSHIPS1900291/1/1919
THE design and construction of airships in the United States was inaugurated by the Navy in 1917, with the B class of sixteen small airships. These were built for training and coast patrol. They were used to train 150 pilots and covered 140,000 miles of patrol without loss of life. The following year the C class of twice the size was brought out and proved very successful. The development of airship construction has progressed rapidly, but because of such a delayed beginning, the United States is still very far behind England and Germany. In particular, the large rigid airships of the Zeppelin type have not yet been attempted here, but their use during the war by the German navy, as scouts over the North Sea, indicates that they are necessary to a modern fleet. A short account is given of the German North Sea air organization, showing the seaplane bases laid out to cooperate with the airships.
HUNSAKER, J C
AIRSHIPS AND THEIR COMMERCIAL POSSIBILITIES1900651/1/1919
Airships were not generally considered important before the war. Many thought they would never become practical as a means of transportation. The proper conception of what an airship is having first been explained, the three principal ways in which progress has been made are specified as weight-saving, improvement of overall propulsion efficiency and decreasing resistance and increase in size. The last mentioned feature is discussed in some detail, the conclusion being that practically anything is possible, given an airship of sufficient size. The future needs of airship development are then considered, such as more suitable engines, multiple powerplants, dependability, the development of better fabric and better landing and hangar facilities.
UPSON, R H
THE CASE FOR THE AIRSHIP1900271/1/1919
ON the basis that it is impossible to state the case for either the airship or the heavier-than-air machine without some comparison of the two, the author discusses relatively features, points of merit or superiority and the fields of usefulness thus far disclosed in the rapid development of the craft. Progress since 1914 is outlined, a brief history to date is included and the way prepared for consideration of the possibilities of long-distance flight. A comparison of the features given emphasizes strongly the point that the airplane is mainly a high-speed, short-distance carrier, while the large rigid airship is essentially a medium-speed long-distance carrier. Each type has a distinct sphere of activity; the airship in transcontinental, transoceanic traffic; the airplane in feeding the terminals of the airship with passengers and, possibly, certain kinds of freight. The salient features of the airship are great endurance, large cargo capacity, ability to remain aloft in bad weather, and space and comfort for passengers. The secondary position of the United States in the rank of development is stated frankly. The non-inflammable lifting gas, of which we have an almost unlimited supply, should place us in the forefront for speedy, long-distance transport.
D'ORCY, LADISLAS
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