PROJECT DESCRIPTION:
ELECTRIC GLIDER USING REGENERATIVE SOARING AND SOLAR POWER
1. Current state-of-art in the field and outcomes of the project
a) Describe current situation of the field in worldwide context including relevant literature
references
General goal of the project is basic research of methods for generating energy for aircraft
propulsion during flight, specifically by conversion of the energy of updrafts into electric
energy (regenerative soaring) and by using solar power. The research includes construction
of an experimental manned aircraft capable of operation independently on fossil fuels.
Description of the current situation concerns the problems of regenerative soaring, electric
aircrafts and the problems of fiber reinforced plastics suitable for aeronautic applications at
higher temperatures.
Regenerative Soaring:
Conventional sailplanes use updrafts to gain altitude. Self launching sailplanes equipped with
propeller can add a regenerative soaring feature, whereby their propeller can be used as a
turbine to recharge stored energy when the aircraft encounters an updraft Because of the
increased drag during regeneration the aircraft can not climb as fast as a clean sailplane but
the energy generated by the turbine can be stored for future use (for aircraft propulsion or to
power devices on board of the aircraft). In the optimal case the aircraft will fly entirely without
fuel or recharging on the ground. MacCready proposed to use this technique to extend the
range of small unmanned aerial vehicles (UAVs) in 1998 [15].
The idea to install an air turbine on an aircraft has a long history. One of the most common
examples is the Ram Air Turbine (RAT), a small turbine that is connected to a hydraulic
pump, or electrical generator, installed in an aircraft and used as a power source. The RAT
generates power from the airstream due to the speed of the aircraft. Modern aircrafts only
use RATs in emergency - in case of the loss of both primary and auxiliary power sources the
RAT will power vital systems. Examples of modern civilian aircrafts using the RAT include
Airbus A380 (RAT diameter 1.63m), Boeing 757 and other. The RAT played a vital role in
successful ditching of the US Airways flight 1549 in Hudson River [8].
Air turbine was not used as an energy source for the aircraft propulsion until now. Research
was performed mainly on computer models [14]. There is an increasing demand for manned
aircrafts and UAVs with high endurance and long range. A possible solution is to use electric
motor and solar power. The problem is a physical limitation on the available energy –
maximal solar power per square meter is app. 1000W. Top efficiency of commercial solar
cells is around 20%. Therefore the aircraft must be light and have a large surface facing sun
to be able to generate enough power for its propulsion. These requirements are difficult to
meet with the present battery technology, especially when the aircraft should stay aloft after
sundown.
Phillip Barnes has described in his paper “Flight Without Fuel - Regenerative Soaring
Feasibility Study” [4] results of the performance analysis of a computer modeled regenerative
soaring sailplane of his own design. Results of this analysis indicate that it is possible to build
an aircraft capable to efficiently use and store the energy of updrafts. The energy of updrafts
can exceed the available solar energy by factor of ten and updrafts exist in lesser extent also
during night time (e.g. upwind slope updrafts). It is possible to utilize the energy of updrafts
and solar energy simultaneously. Phillip Barnes (chief engineer in Northrop Grumman, see
Acknowledgements) has consulted details of this project proposal.
Electric Aircrafts:
Electric motors are widely used in remotely controlled (RC) airplanes and in several manned
airplanes. The limiting factor application of electric motors in aviation is the energy storage.
Batteries or ultracapacitors provide low energy to weight ratio (still, batteries are the third
most energy dense energy storage after nuclear and chemical fuel) and therefore electric
airplanes have a small range. Solar and atmospheric energy can be used to increase the
range and duration of the flight.
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Helios Prototype was an ultra-lightweight flying wing UAV with a wingspan of 75.3m,
powered by solar cells, batteries and a hydrogen-air fuel cell build by NASA. Helios belonged
to an evolutionary series of UAVs (with Pathfinder, Pathfinder Plus and Centurion [9], [5])
built to develop technologies that would allow long-term, high-altitude aircraft to serve as
"atmospheric satellite".
Sunseeker II was as of Dec. 2008 the only manned solar powered airplane in flying
condition. In 2009 it became the first solar-powered aircraft to cross the Alps. Its solar array
charges lithium-polymer battery powering a 6kW electro motor. Max speed on solar power is
64kph. Sunseeker II is basically a motor glider recharging battery while gliding using solar
power [10].
Several self launching electric sailplanes appeared on the market recently e.g. Antares 20E
of Lange Aviation [11]. Antares 20E is equipped with 42kW electric motor. It climbs to 3000
meters in app. 13 minutes when the batteries are depleted. DLR (German Aerospace
Center) has modified Antares 20E for using fuel cells [12].
One of the most ambitious of the known projects of solar aircrafts is Solar Impulse. The
proposed manned aircraft is intended to circumnavigate the globe in several 3-4 days long
legs. The estimated budget is 70mil USD. The wingspan of the aircraft is 63m and it weights
1600kg. The record attempt is expected in 2012 [12], [13].
Electric Aircraft Corporation [1] made electric flight accessible to wide public. This company
produces two types of electric aircrafts: rigid wing Electraflyer-C and Electraflyer trike (motor
hang glider with Stratus wing). Randall Fishman (president of Electric Aircraft Corporation,
see Acknowledgements) has consulted details of this project proposal.
Self launching electric sailplanes are very suitable for regenerative soaring. Electric motor
with propeller can serve for both purposes – for propulsion and for energy generation [4].
Integration of solar cells into the propulsion-energy generation system is relatively simple.
The problems to be solved include development of a propeller efficient in both modes [4].
Another problem of solar aircrafts is the excessive heat absorbed by the solar cells, which
would be otherwise reflected by the traditional white finish. It is necessary to choose
appropriate construction and/or materials resistant to higher temperatures. General problem
of electric aircrafts is also waterproofing for protection of the electric system.
Fiber Reinforced Plastics:
Optimal shape and weight of the aircraft is presently possible to achieve using composite
materials properly known as fiber reinforced plastic (FRP). Composite systems based on
resin matrices reinforced with glass, carbon or Kevlar fibers are widely used in construction
of light aircrafts including sailplanes and hang gliders. Glass fibers have low price and high
resistance to heavy deformations but their high elasticity may cause problems sometimes.
Carbon fibers on the other hand have complementary features. Kevlar fibers have
exceptional tensile strength but their resistance to pressure is low.
There are different manufacturing processes for composite components depending on the
size of the component, number of the components to be made and the requirements on the
thermal processing of the material (overview in [18]). Epoxy resin reinforced with fibers of
any type inserted into form in liquid state (the so called wet-process) and hardened at room
temperature is used the most. This process makes building of very large components
possible without the risk of deformation but the resulting thermal resistance of the component
is limited to app. 80°C. Higher thermal stability may be achieved either by hardening of the
epoxy resin at higher temperature (200-300°C) or by using a special resin. Hardening of the
resin at higher temperature requires the fibers to have similar thermal expansion coefficient.
In practice, this problem is manageable when using epoxy resin, carbon fibers and heat
treatment in autoclave (as by military aircrafts). Rare examples of application of this solution
are the recently developed ultralight sailplane SparrowHawk [19] from USA or an older
sailplane PIK-20 from Finland (Jukka Tervamaki, see Acknowledgements, build a prototype
for a production motor glider PIK-20E under designation JT-6. J. Tervamaki has consulted
details of this project proposal).
Another solution is to use thermaly stable resins. Commercially available at reasonable price
are bismaleimide resins with vitrification temperature around 300°C [3]. During the last 20
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years much progress was achieved in the field of polyimide resins mainly thank to NASA.
Their price makes them acceptable also for other than military and space applications. All
solutions achieve stability of mechanical properties at temperatures of more than 200°C.
Application of solar cells requires approximately half of this value (~100°C). It is likely that
this resistance can be achieved using a cheaper and simpler method, either by using a
sandwich structure or by additional thermal treatment after the traditional wet-process.
Definite answer to this question will be given after the thermal analysis and testing of the
samples.
b) Describe ability of the project proposal to expand knowledge beyond existing borders in
the relevant field
The possibility to convert and store the energy of updrafts for propulsion of an aircraft was
not practically tested until now. There is a lack of experimental data and of components
optimized for regenerative soaring (such as a propeller efficient also as a turbine). The goal
of the project is to prepare a base for the development of technologies enabling production of
a new category of aircrafts capable of highly ecological operation. The contribution of the
project will be represented by the results of analyses of alternative solutions (e.g. comparison
of the properties of a fixed and a variable pitch propeller, evaluation of a ducted fan solution
for regenerative soaring), by the collected and analyzed experimental data and by the
designs optimized based on the experimental and analytical results.
The proposed aircraft will be the first of its kind and the second manned solar powered
aircraft in flying condition. The experimental results would be valuable for the progress in the
field of green aviation and for the development of multipurpose long term long range UAVs.
Compared to the majority of present projects the proposed aircraft is not intended for
operation in high altitudes. Its price and parameters are similar as of a motor glider with
combustion engine. The aircraft would enable to research the energy gain from regenerative
soaring under various conditions directly and also to evaluate the gain from using solar
power and regenerative soaring simultaneously. The aircraft has potentially a longer range
than a standard sailplane and it is more resistant to temporally adverse meteorological
conditions. Considering that the energy of updrafts can exceed the available solar energy by
factor of ten it is possible to maintain small dimensions and sturdy structure of the aircraft.
UAVs using solar power and regenerative soaring (rsp. dynamic soaring) can potentially stay
aloft indefinitely and serve for different purposes including long term observation of traffic,
data collection during rescue operations or catastrophic events, scanning or mapping of the
surface of Earth using flock of UAVs to cover large areas (e.g. when searching for missing
persons, creating 3D model of the surface, etc.) or observation of migrant animals. Futuristic
applications include deploying autonomous soaring UAVs at Mars for planetary research.
The proposed aircraft can serve as a platform for development of an intelligent control
system for autonomous flight and for modification to an autonomous UAV.
Development of the artificial intelligence system of the UAV exceeds the financial and the
conceptual frames of this project, however.
2. Project objectives
a) Describe project objectives for duration of the project and for its particular stages
The general objective of the project is basic research of methods for generating energy for
aircraft propulsion during flight, namely by conversion of the energy of updrafts into electric
energy (regenerative soaring) and by using solar power. The experimental platform is the
proposed manned aircraft capable of operation independently on fossil fuels. The proposed
aircraft is equipped with a propeller and an electric motor powered by a lithium-polymer
battery and features a propulsion-energy generation system not used so far. The proposed
aircraft is capable of self launch, day time flight and landing with fully charged battery ready
for the next launch. The proposed aircraft will serve for verification of the concept of
regenerative soaring, data collection, analysis of the efficiency of the combined system of
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energy generation and as an experimental platform for future research. Advantages of the
proposed aircraft include clean and inexpensive operation and independence on fuel or
recharging on ground.
Partial objectives of the project (name, period from-to mm/yyyy)
1. Establishing and updating a web-portal for project propagation (05/2011-10/2014).
The web-portal will provide updated information on project progress, contact with public by
means of electronic discussion and other services.
2. Design of airfoil and its manufacturing process (05/2011-05/2013). The base for the
design of the airfoil is a rigid wing hang glider SWIFT [17]. The objective includes: design of
the airfoil, primary and secondary controls, the internal equipment of the airfoil, installation of
solar cells, distribution of solar cells and coverage optimization, production processes,
computer modeling and analyses of mechanical and thermal loads, analyses of alternative
solutions (e.g. installation of flexible solar cells on the surface of the airfoil, installation of rigid
or flexible solar cells inside the airfoil under translucent covers etc.), design of transportation
container and other related activities.
3. Design of pilot nacelle (cockpit) and its manufacturing process (05/2011-05/2013).
The objective includes design of the pilot nacelle (cockpit) and its manufacturing process,
selection of used materials, design and analysis of pilot’s position (sitting or hanging), design
of installation of the propulsion unit, batteries, accessories, safety elements (rocket
parachute and other), design of landing gear, design of means for integrating the nacelle with
the airfoil and other related activities.
4. Design of propeller suitable for operation in propulsion and energy producing
modes (05/2011-05/2013). The objective includes design, modeling and analyses of
alternative solutions (fixed propeller with symmetrical blade sections, variable pitch
propeller), propeller blades, propeller hub, production process, selection of used materials
and components and other related activities.
Note: Design work within the objectives 2-4 is coordinated and based on the parameters of
the propulsion-energy generation system.
5. Testing of samples (09/2011-12/2013). The objective includes manufacturing of samples,
design and realization of mechanical tests of samples at normal and elevated temperature,
tests of physical, electric and mechanical properties of the products with installed solar cells
and other related activities. Test results will continuously serve for optimization of designs
within objectives 2-4 and 13.
6. Design and implementation of the energy production system and integration of
propulsion and energy production systems (05/2011-05/2013). The objective includes
selection of solar cells, design of wiring and integration to the propulsion-energy generation
system, design of systems monitoring state and activity of the solar cells’ array, design of the
charging subsystem, design of the control module for coordination of energy production
subsystems and propulsion subsystem including utilization of the energy produced by
regenerative soaring, design of control elements of the systems, realization of the above and
other related activities.
7. Design and implementation of communication sensing recording and data display
systems (05/2011-05/2013). The objective includes selection of sensors for collecting flight
and experimental data, aircraft state data, pilot activity data, propulsion-energy generation
system state data, navigation data, design and selection of avionics, communication
equipment, design of the integrated system for data collecting, recording and display, control
elements of the communication, data collection, recording and display systems, software
development, realization of the above and other related activities.
8. Manufacturing of components, aircraft assembly (09/2011-08/2014). The objective
includes manufacturing of laminating forms and tools for manufacturing the aircraft’s
components (airfoil, nacelle, propeller and other), manufacturing of the components, internal
equipment of the airfoil, installation of the propulsion-energy generation system, installation
of systems for communication, data collection, recording and display and other related
activities. Besides manufacturing the airfoil with installed solar cells, manufacturing an airfoil
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without solar cells is planned for the purposes of aerodynamic and static testing, optimization
of the work process and other related purposes.
9. Testing in controlled environment (09/2011-10/2014). The objective includes design,
realization and evaluation of tests in controlled environment, tests of models of components
and the aircraft in wind tunnel, experimental determination of the propeller efficiency in
propulsion and turbine modes, static tests and other related tests performed for the purpose
of verification of functionality and reliability of the components, experimental analysis and
data collection, optimization of designs, manufacturing processes and other related
purposes.
10. Optimization of designs and manufacturing processes, establishing direction of
future research (06/2013-10/2014). The objective includes modifications of designs and
manufacturing processes based on experiences and test results, experiments and analyses
performed in the project, determination of the problems to be solved and the scope of future
research and other related activities.
11. Experimental analysis of the propulsion - energy production system, performance
maximization (06/2011-10/2014). The objective includes design, realization and evaluation
of experiments, collecting experimental data, experimental analysis of the propulsion-energy
generation system efficiency in not controlled environment, pilot activity modeling and other
related activities.
12. Dissemination of results, publishing (05/2011-10/2014). The objective includes
dissemination of project outcomes, publication of results including publication of master’s and
PhD. theses, project advertisement and other related non-commercial activities.
b) Define originality and innovativeness of objectives proposed
The idea to transform energy of updrafts into electric energy was not tested so far. Many of
the partial objectives focus on problems which were not yet solved (e.g. propeller efficient in
propulsion and turbine modes, evaluation of the efficiency of energy production during flight)
or did not appear in such application (determination of mechanical properties of composites
exposed to higher temperatures, control of generation and storing of electric energy during
flight). Design of the aircraft will also provide new insight into known problems (e.g.
aerodynamics of a self-wing). Despite that the project priority is to test the idea of
regenerative soaring, research work on the aircraft design will produce solutions to problems
less critical from the perspective of project success but scientifically interesting (e.g.
ergonomics of the cockpit, properties during unusual flight modes)
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3. Methodology
a) Briefly describe your planned approach to reach the goals, in order to evaluate their
feasibility
Feasibility analysis
The aircraft:
Pic. 1. SWIFT [17] a SWIFT Light Pas [2].
Glide ratio (at 75km/h est.*) [2]
24:1
Minimum sink rate (at 45km/h) [2]
0.65ms-1
Never to exceed speed (VNE) [2]
120 km/h
Climb rate (est.*)
1ms-1
Wing area [2]
12.5m2
Maximum load [2]
+5.3g/-2.65g
tested +7.95g/-3.98g
Weight empty [2]
48kg
Payload:
battery pack (5.6kWh [1])
el. motor (13.5kW [1])
solar array
equipment and accesories, avionics etc.
Pilot
Gross weight
35kg
12kg
10kg
15kg
~80kg
~200kg
Table 1. Specifications of the proposed aircraft (* expert estimate based on information on
SWIFT Light Pas [2], Electraflyer Trike [1], consulted with the manufacturers).
The conceptual base for the proposed aircraft is an ultralight rigid wing hang glider SWIFT
[17], Pic. 1., combining low weight, large surface of the airfoil and superb flight performance
[2]. It was designed by Bright Star Gliders in collaboration with engineers at Stanford
University. Although it is a fully-cantilevered rigid wing with aerodynamic controls and flaps, it
weighs only 48 kg and is easily transported on the top of a car. SWIFT is easy to adapt to
accept engine kit (combustion engine, steerable front wheel, disk brake, wheeled tiplets for
taxing). Solar cells will be installed in the airfoil during the manufacturing process. The
materials used (especially the resin) will be specified after analysis of the thermal load of the
airframe. The mechanical properties of the fiber reinforced plastic will tested at higher
temperatures.
The pilot nacelle (cockpit) will be designed for the specific requirements of the project anew.
We propose installation of the Electraflyer [1] propulsion system consisting among others
from a lithium-polymer battery pack with 5.6kWh capacity [1] and brushless 13.5kW electric
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motor. This system is used to in an USA certified motor hang glider and it is possible to adapt
it for regenerative soaring (the electric motor works as generator with 90% efficiency). Table
1 summarizes the specifications of the proposed aircraft.
Energy balance:
Theoretical analysis was performed to evaluate the possibility of building an electric aircraft
capable of self launch, long daytime flight and landing with a full battery. The investigated
scenario consists of 5 phases:
1. Self launch and climb to 300m
2. 20 minutes cruise in search for updrafts
3. Recharge batteries to full capacity
4. Cruise till 50% of the battery capacity remains.
5. Recharge batteries to full capacity and land
The analysis required estimates of certain values. The estimated values were carefully
calculated, consulted with independent experts (see Acknowledgments) and adjusted to
slightly under or over estimate the actual values against the benefit of the aircraft. Only the
energy balance considering the electric energy was calculated. The fact that the aircraft can
utilize the gained altitude as a standard sailplane was ignored.
The proposed battery pack lasts for 1-1.5 hours of Electraflyer trike's powered flight. The
aerodynamics of the proposed aircraft is better than of the trike with the same weight.
Therefore it is assumed that the battery pack will last for at least 1.5 hours of flight what
corresponds to the average motor input of 3.7kW. The estimated efficiency of the proposed
propeller in turbine mode is 85% ([4], efficiency of airborne turbine is defined differently than
efficiency of a ground based turbine and Betz limit does not apply here). When the propeller
works in a turbine mode it creates drag which leads to increased sink rate. We assume that
increasing the sink rate by 0.75ms-1 will not seriously impair the flight performance of the
aircraft (resulting accumulated sink rate is 1.4 ms-1). This increase of sink rate corresponds
by the given gross weight of the aircraft and the overall efficiency of energy conversion
(turbine efficiency x generator efficiency 90%) to 1126W of the generator output (for
comparison, the approximate output of a ground based wind turbine with 1.5m diameter is
1400W at 15°C, 1500m AMSL, 65km/h wind speed and 25% efficiency). The battery charger
works with 80% estimated efficiency. We estimate that 80% (10m2) of the wing area can be
used to install solar cells. The efficiency of solar cells suitable for airplanes varies between
~6% and ~20%. We assume installing solar cells with 15% efficiency providing maximum
output of 150W per m2. The solar cells are estimated to provide on average 70% of their
maximum output during cruising (the wing is not always in the optimal position relative to the
sun). The solar cells are estimated to provide on average 40% of their maximum output
during regeneration (the aircraft is moving in banked turns and the wing is only part of the
time exposed to the sun). The electric equipment of the aircraft is estimated to consume 10W
on average.
The analysis has shown that it is possible to build an aircraft powered with solar power and
regenerative soaring so that it would be capable to self launch, fly and land with full battery.
The total flight time in the investigated scenario was 4 hours and 26 minutes. In this
configuration the ratio between free cruising and regeneration was 1:2 which means that the
aircraft would need to regenerate for 2 minutes for every minute of powered cruising to have
the batteries fully charged at landing. The analysis shows that using regenerative soaring in
combination with solar power shortens the recharge time significantly. To maximize the
efficiency of the aircraft, solar cells should cover the maximum of the suitable surfaces and
have the highest possible efficiency, input of the equipment should be minimized, drag of the
aircraft should be minimized, large and slow (more efficient) propeller should be used.
Details of the analysis are provided here [16].
Approach to reach the goals:
The initial step will be establishment of a web-portal serving for information of the public
about the project progress in English and Slovak languages and as an output of an online
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project management software providing updated information on the status of partial
objectives to the members of the project team. During 2011, among others the components
of the propulsion system will be purchased and testing and analysis of installation solutions
(especially for the battery pack) will start. The selected SWIFT airfoil is documented in
scientific publications [17]. Selection of an existing proven airfoil will save significant financial
and personal resources. It will be necessary to design the internal construction of the airfoil
and the manufacturing process. Design of the airframe and of the propeller will be aided by
CAD software, software for simulation of thermal and mechanical loads and software
simulator of flowing fluids. Selection of heat resistant materials will depend on the results of
thermal load analysis and on the test results obtained on samples (in 2011, samples of solar
cells will be purchased and samples of fiber reinforced plastics with and without installed
solar cells will be manufactured). There are two basic solutions for installing solar cells: 1.
Installation of flexible solar cells on the surface of the airfoil during lamination and 2.
Installation of flexible or rigid solar cells (with higher efficiency) inside the airfoil under
translucent covers. Based on the analysis and the tests the most suitable solution and type
of solar cells will be selected. Simultaneously with the design of the airfoil, design of the
nacelle (cockpit) will start. The nacelle on the contrary to the airfoil will be designed anew,
ergonomically and with the emphasis on maximal drag reduction. Design of the nacelle will
follow analysis of several alternative solutions concerning mainly the pilot’s position (sitting or
hanging), forming and placement of the battery pack, placement of the data display,
placement of the propulsion unit and placement of safety elements (rocket parachute etc.).
Placement of the propulsion unit is to a large extent dependent on the diameter of the
proposed propeller. Large, slow propellers are more efficient but they must be installed
higher above ground to prevent the blades to hit the ground. A solution of extending console
holding the propulsion unit will be analyzed. The console is to be retracted after start to
reduce drag and to bring the trust vector closer to the centre of gravity of the aircraft. Design
of the propeller will be also started simultaneously with the design of the airfoil and of the
nacelle. The research groups will closely cooperate. Manufacturing of several scaled models
of the propeller for testing is planned.
Design and realization of the propulsion-energy generation system will be performed
simultaneously with the design of the airframe and the propeller and the design and
realization of the communication, sensing, recording and data display systems as well. The
activities will be performed using software and laboratories for modeling of electric circuits.
Because the focus of the project is in the basic research of methods for generating energy
during flight, development of the mentioned systems assumes utilization and integration of
several commercial products (e.g. rugged PC with touchscreen, avionics etc.). The main
research work will be done by designing an efficient in flight charging system and developing
software for data collection, recording and display.
Testing of samples and testing in controlled environment will take place since 2011. Design
work will be finished in 2013. A scaled model for testing purposes will be build (testing in
wind tunnel, confirmation of flight characteristics, stability and identification of control
deviations). Manufacturing of some components the design of which has been finished (e.g.
negative laminating forms for the airfoil, manufacturing of the airfoil prototype without solar
cells) will start in 2012. Manufacturing of the airfoil with solar cells and assembly of the
aircraft is planed for 2013. Research work on optimization of the designs and the
manufacturing processes will take place since 2013.
The most valuable source of information will be the experimental analysis of the propulsionenergy generation system in uncontrolled environment. The experiments are planned for
warmer months of 2013 and 2014 when the weather is suitable for soaring. The outcomes
and results of the project will be published throughout the duration of the project. The
demonstration flight promoted in the media is planned for 2014.
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4. Outcomes and impacts of the project
a) Describe the results and expected outcomes of the project in its particular objectives and
quantify them
1. Establishing and updating a web-portal for project propagation (05/2011-10/2014),
the outputs: 1x web-portal on an individual domain with editorial system for updating,
information in English and Slovak languages, online discussion and contact information.
2. Design of airfoil and its manufacturing process (05/2011-05/2013), the outputs: 1x
technical documentation of the airfoil and its manufacturing process, 1x scaled model, 1
current content publication, 2 publications in peer-reviewed scientific journals, 1 publication in
proceedings and non-reviewed journals, 1 PhD. student which will be trained within project, 1
Master thesis accomplished within the project.
3. Design of pilot nacelle (cockpit) and its manufacturing process (05/2011-05/2013),
the outputs: 1x technical documentation of the nacelle (cockpit) and its manufacturing
process, 1x scaled model, 3 publications in peer-reviewed scientific journals, 1 PhD. student
which will be trained within project, 1 Master thesis accomplished within the project.
4. Design of propeller suitable for operation in propulsion and energy producing
modes (05/2011-05/2013), the outputs: 1x technical documentation of the propeller and its
manufacturing process, 1x scaled model, 1 current content publication, 2 publications in
peer-reviewed scientific journals, 1 publication in proceedings and non-reviewed journals, 1
Master thesis accomplished within the project.
5. Testing of samples (09/2011-12/2013), the outputs: test results, 3 publications in peerreviewed scientific journals, 1 Master thesis accomplished within the project.
6. Design and implementation of the energy production system and integration of
propulsion and energy production systems (05/2011-05/2013), the outputs: : 1x
technical documentation of the energy production system and integration of propulsion and
energy production systems and their assembly, 1x integrated propulsion-energy generation
system, 1 current content publication, 2 publications in peer-reviewed scientific journals, 1
publication in proceedings and non-reviewed journals, 1 PhD. student which will be trained
within project, 2 Master theses accomplished within the project.
7. Design and implementation of communication sensing recording and data display
systems (05/2011-05/2013), the outputs: 1x technical documentation of communication
sensing recording and data display systems and their assembly, 1x communication sensing
recording and data display systems, 2 publications in peer-reviewed scientific journals, 1
publication in proceedings and non-reviewed journals, 1 PhD. student which will be trained
within project, 2 Master theses accomplished within the project.
8. Manufacturing of components, aircraft assembly (09/2011-08/2014), the outputs:
lamination forms and tools for manufacturing of the aircraft’s components (airfoil, nacelle,
propeller etc.), transport container, 1x airfoil including internal equipment without solar cells,
1x nacelle (cockpit) with installed propulsion-energy generation system, communication
sensing recording and data display systems, 1x transport container.
9. Testing in controlled environment (09/2011-10/2014), the outputs: test results, 1
current content publication, 2 publications in peer-reviewed scientific journals, 1 Master
thesis accomplished within the project.
10. Optimization of designs and manufacturing processes, establishing direction of
future research (06/2013-10/2014), the outputs: technical documentation of the modified
designs and manufacturing processes, 2 publications in peer-reviewed scientific journals, 1
PhD. student which will be trained within project, 1 Master thesis accomplished within the
project.
11. Experimental analysis of the propulsion - energy production system, performance
maximization (06/2011-10/2014), the outputs: experimental analysis results, 1 current
content publication, 3 publications in peer-reviewed scientific journals, 1 publication in
proceedings and non-reviewed journals, 1 PhD. student which will be trained within project, 1
Master thesis accomplished within the project.
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12. Dissemination of results, publishing (05/2011-10/2014), the outputs: together 31
publications: 5 current content publications, 21 publications in peer-reviewed scientific
journals, 5 publications published in proceedings and non-reviewed scientific journals. 11
Master theses will be accomplished within the project and 10 PhD. students will be trained
within the project. 1x demonstration flight promoted in the media, the project web-portal.
b) Describe your plan for dissemination and exploitation of the project results
The project results will be disseminated mainly through the publications and through the
bilingual project web-portal established for this purpose. During the preparation of the project
contact was established with companies and persons active in given area, further
cooperation is expected. The project results will be useful mainly in the development of long
term UAVs operating in lower altitudes (see also 1.c) and also in the development of green
aircrafts with very low operational costs and relatively low price for sporting aviation.
References:
[1]
Electric Aircraft Corporation, http://www.electraflyer.com/ [retrieved 2010-07], email
correspondence with Randall Fishman, president of the Electric Aircraft Corporation
[2]
Aériane SWIFT Light, SWIFT Light Pas, http://www.aeriane.com [retrieved. 2010-07],
communication with the company representatives
[3]
Baker, A. (2004) Composite Materials for Aircraft Structures (Aiaa Education Series),
AIAA (American Institute of Aeronautics & Ast; 2 edition, ISBN: 1563475405.
[4]
Philip Barnes - Pelican Aero Group, Flight Without Fuel - Regenerative Soaring
Feasibility Study, presented at General Aviation Technology Conference & Exhibition,
August 2006, Wichita, KS, USA, Session: Propulsion Dynamics and Advanced Engine
Concepts,
http://www.sae.org/technical/papers/2006-01-2422,
presentation
at:
http://esoaring.com/barnes_regen_soaring_theory.ppt, [retrieved 2010-07], email
correspondence with Philip Barnes.
[5]
NASA Dryden Fact Sheet - Pathfinder Solar-Powered Aircraft,
http://www.nasa.gov/centers/dryden/news/FactSheets/FS-034-DFRC.html,
[retrieved 2010-07]
[6]
Resins for the Hot Zone, In: High-Performance Composites, 6/19/2009.
http://www.compositesworld.com/articles/resins-for-the-hot-zone-part-i-polyimides,
[retrieved 2010-07-01].
[7]
J. Wharington, I. Herszberg (1998), 'Control of High Endurance unmanned air vehicle',
Proc. 21st Congress of the International Council of the Aeronautical Sciences, Rodney
S. Thomson & Murray L. Scott, eds., AIAA Electronic Publication - CD ROM, ISBN:156347 287-2 98-1141, (ICAS '98, 13-18 Sept. '98 - RMIT Fishermen's Bend, Melb.
Vic.)
[8]
Wald, Matthew L. (2009-01-17). "Investigators Offer Details of Flight’s Few Minutes",
Manhattan (NYC): NYTimes.com,
http://www.nytimes.com/2009/01/18/nyregion/18plane.html?_r=1&hp. [retrieved 201007].
[9]
Dryden Flight Research Center, report,
http://www.nasa.gov/centers/dryden/news/ResearchUpdate/Helios/index.html,
[retrieved 2010-07].
[10] http://solar-flight.com/, [retrieved 2010-07].
[11] http://www.lange-aviation.com/htm/english/products/antares_20e/antares_20E.html,
[retrieved 2010-07].
[12] The Economist, Technology Quarterly, 12th June 2010, Hight Voltage (Electric
Planes), http://www.economist.com/node/16295620?story_id=16295620
[13] http://www.solarimpulse.com/, [retrieved 2010-07].
[14] Allen, Michael J. (2005) Autonomous Soaring for Improved Endurance of a Small
Uninhabited Air Vehicle. Meeting Presentation AIAA-2005-1025, Research
Engineering, NASA Dryden Flight Research Center.
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[15]
[16]
[17]
[18]
[19]
MacCready, P. B. (1998) “Regenerative Battery-Augmented Soaring”, Self-Launching
Sailplane Symposium, National Soaring Museum, Elmira, New York, July 16, 1998.
Feasibility Analysis,
http://neuron.tuke.sk/~bundzel/EGURS/Feasibility_Analysis_EN.pdf
Kroo, I. (2000) Design and Development of the SWIFT - A Foot-Launched Sailplane,
Invited Paper, AIAA Applied Aerodynamics Conference and Exhibit, 18th, Denver, CO,
Aug. 14-17, 2000
Long, A. C. (2005) Design and Manufacture of Textile Composites, Cambridge:
Woodhead, ISBN 1855737442.
Windward Performance website,
http://www.windward-performance.com, [retrieved 2010-07].
Acknowledgements:
We would like to thank to the following independent experts who consulted the details of the
project proposal
Phil Barnes is Principal Engineer at Northrop Grumman Corporation. He has a Master’s
Degree in Aerospace Engineering from Cal Poly Pomona and a Bachelor’s Degree in
Mechanical Engineering from the University of Arizona. He has 25-years of experience in the
performance analysis and computer modeling of aerospace vehicles and subsystems at
Northrop Grumman. Phil has authored technical papers on aerodynamics, gears, and flight
mechanics. Phil Barnes is the author of the paper “Flight Without Fuel - Regenerative
Soaring Feasibility Study” [4]
Randall Fishman is the president of Electric Aircraft Corporation. He has won numerous
awards and accolades for his work on electric flight and already has built an electric-powered
ultralight and a single-seat motor glider. In April 2007 the Electric Aircraft Corporation began
offering complete electric ultralights and engine kits under the ElectraFlyer brand name, to
convert existing ultralight aircraft to electric power, in what is the first commercial offering of
an electric aircraft.
Jukka Tervamaki graduated from the Helsinki University of Technology in 1963 specialized
in Aeronautical Engineering. Experimenting, creating, designing and building has been
everyday work as well as a hobby for him for four decades. He designed and build several
rotary wing aircrafts (autogyros), a motor glider and cooperated on development of a fixed
wing tow plane. He has logged total 2200 flight hours of which 150 hours in autogyros. He is
aviation writer for several Finnish and foreign aviation magazines.
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