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University of Pretoria
1.
[No author].
Longitudinal handling characteristics of a tailless
gull-wing aircraft
.
Degree: 2008, University of Pretoria
URL: http://upetd.up.ac.za/thesis/available/etd-09182008-132941/ 
A handling quality investigation was performed on
the swept gull-wing configuration. The swept gull-wing
configuration is tailless and has a wing with a transition in the
sweep and dihedral angle. An example of this type of aircraft is
the Exulans. This aircraft is currently under development at the
University of Pretoria. The handling quality study was focussed on
pitch axis dynamics. The Exulans is a research testbed that will be
used to investigate the swept gull-wing configuration and its
special controls by means of full-scale flight testing. Variable
wing sweep, twisting elevons and winglets will be investigated as
means of control. These control devices are configured in such a
way as to have minimum impact on the performance of the aircraft.
The handling qualities of the swept gull-wing configuration have to
be acceptable while using these different control strategies. The
study was launched to investigate whether a gull-wing configuration
aircraft will have satisfactory handling qualities at CG positions
associated with the most favourable aerodynamic performance. There
is an aerodynamic performance gain in designing an aircraft so that
the CG falls on the so-called `E-point'. The E-point is the centre
of pressure for an elliptical circulation distribution. An
elliptical circulation distribution is associated with the highest
Oswald efficiency for an aircraft. Time domain simulation
techniques and frequency domain analysis techniques were used to
analyse the handling qualities of the gull-wing configuration. The
C-star criterion was used to analyse handling qualities with time
domain simulation data as input. Comparative time domain
simulations were performed between the Exulans and other aircraft
to compare handling qualities. Eigenvalue analysis was used
together with the thumbprint criterion to investigate inherent
gull-wing airframe dynamics. The Shomber-Gertsen and Military
Specification 8785 criteria were also used for the same purpose.
The Neal-Smith method was used to investigate the effect of control
authority on handling qualities and the effect of a pilot. The
Monnich and Dalldorff criterion was used to evaluate gust handling
qualities. An analysis chart by Fremaux and Vairo was used to
evaluate the tumbling susceptibility of the gull-wing
configuration. The pitch handling quality investigation shows
sufficient promise that the swept gull-wing configuration will have
acceptable handling qualities with the CG placed at positions
associated with optimised aerodynamic performance. Analysis showed
that the swept gull-wing configuration is potentially prone to
tumbling. With low static margins, the configuration should exhibit
improved handling qualities in gusty conditions when compared to
existing tailless aircraft. It is recommended that a lateral
handling quality study be performed before full scale flight
testing commences on the Exulans. In addition, the possibility of
wingtip stall must be investigated for the case of the swept
gull-wing configuration.
Advisors/Committee Members: Theron, Nicolaas J (advisor).Subjects/Keywords: Flight simulation;
Tumbling;
Thumbprint criterion;
Neal-smith analysis;
C-star criterion;
Shomber-gertsen analysis;
Pilot induced oscillation;
Oswald efficiency;
Pilot mathematical model;
Variable sweep wing;
Exulans;
Variable static margin;
Swept gull-wing configuration;
O-point;
E-point;
Handling qualities;
Gust handling qualities;
Tailless aircraft;
Pecking;
Monnich and dalldorff criterion;
UCTD
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APA (6th Edition):
author], [. (2008). Longitudinal handling characteristics of a tailless
gull-wing aircraft
. (Masters Thesis). University of Pretoria. Retrieved from http://upetd.up.ac.za/thesis/available/etd-09182008-132941/
Chicago Manual of Style (16th Edition):
author], [No. “Longitudinal handling characteristics of a tailless
gull-wing aircraft
.” 2008. Masters Thesis, University of Pretoria. Accessed January 24, 2021.
http://upetd.up.ac.za/thesis/available/etd-09182008-132941/.
MLA Handbook (7th Edition):
author], [No. “Longitudinal handling characteristics of a tailless
gull-wing aircraft
.” 2008. Web. 24 Jan 2021.
Vancouver:
author] [. Longitudinal handling characteristics of a tailless
gull-wing aircraft
. [Internet] [Masters thesis]. University of Pretoria; 2008. [cited 2021 Jan 24].
Available from: http://upetd.up.ac.za/thesis/available/etd-09182008-132941/.
Council of Science Editors:
author] [. Longitudinal handling characteristics of a tailless
gull-wing aircraft
. [Masters Thesis]. University of Pretoria; 2008. Available from: http://upetd.up.ac.za/thesis/available/etd-09182008-132941/
University of Pretoria
2.
Agenbag, Daniel
Sarel.
Longitudinal
handling characteristics of a tailless gull-wing
aircraft.
Degree: Mechanical and Aeronautical
Engineering, 2008, University of Pretoria
URL: http://hdl.handle.net/2263/28011
A handling quality investigation was performed on the
swept gull-wing configuration. The swept gull-wing configuration is
tailless and has a wing with a transition in the sweep and dihedral
angle. An example of this type of aircraft is the Exulans. This
aircraft is currently under development at the University of
Pretoria. The handling quality study was focussed on pitch axis
dynamics. The Exulans is a research testbed that will be used to
investigate the swept gull-wing configuration and its special
controls by means of full-scale flight testing. Variable wing
sweep, twisting elevons and winglets will be investigated as means
of control. These control devices are configured in such a way as
to have minimum impact on the performance of the aircraft. The
handling qualities of the swept gull-wing configuration have to be
acceptable while using these different control strategies. The
study was launched to investigate whether a gull-wing configuration
aircraft will have satisfactory handling qualities at CG positions
associated with the most favourable aerodynamic performance. There
is an aerodynamic performance gain in designing an aircraft so that
the CG falls on the so-called `E-point'. The E-point is the centre
of pressure for an elliptical circulation distribution. An
elliptical circulation distribution is associated with the highest
Oswald efficiency for an aircraft. Time domain simulation
techniques and frequency domain analysis techniques were used to
analyse the handling qualities of the gull-wing configuration. The
C-star criterion was used to analyse handling qualities with time
domain simulation data as input. Comparative time domain
simulations were performed between the Exulans and other aircraft
to compare handling qualities. Eigenvalue analysis was used
together with the thumbprint criterion to investigate inherent
gull-wing airframe dynamics. The Shomber-Gertsen and Military
Specification 8785 criteria were also used for the same purpose.
The Neal-Smith method was used to investigate the effect of control
authority on handling qualities and the effect of a pilot. The
Monnich and Dalldorff criterion was used to evaluate gust handling
qualities. An analysis chart by Fremaux and Vairo was used to
evaluate the tumbling susceptibility of the gull-wing
configuration. The pitch handling quality investigation shows
sufficient promise that the swept gull-wing configuration will have
acceptable handling qualities with the CG placed at positions
associated with optimised aerodynamic performance. Analysis showed
that the swept gull-wing configuration is potentially prone to
tumbling. With low static margins, the configuration should exhibit
improved handling qualities in gusty conditions when compared to
existing tailless aircraft. It is recommended that a lateral
handling quality study be performed before full scale flight
testing commences on the Exulans. In addition, the possibility of
wingtip stall must be investigated for the case of the swept
gull-wing configuration.
Advisors/Committee Members: Theron, Nicolaas J. (advisor).Subjects/Keywords: Flight
simulation;
Tumbling; Thumbprint
criterion; Neal-smith
analysis; C-star
criterion;
Shomber-gertsen analysis; Pilot induced
oscillation; Oswald
efficiency; Pilot
mathematical model; Variable sweep
wing;
Exulans; Variable
static margin; Swept
gull-wing configuration;
O-point;
E-point; Handling
qualities; Gust handling
qualities; Tailless
aircraft;
Pecking; Monnich and
dalldorff criterion;
UCTD
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Agenbag, D. (2008). Longitudinal
handling characteristics of a tailless gull-wing
aircraft. (Masters Thesis). University of Pretoria. Retrieved from http://hdl.handle.net/2263/28011
Chicago Manual of Style (16th Edition):
Agenbag, Daniel. “Longitudinal
handling characteristics of a tailless gull-wing
aircraft.” 2008. Masters Thesis, University of Pretoria. Accessed January 24, 2021.
http://hdl.handle.net/2263/28011.
MLA Handbook (7th Edition):
Agenbag, Daniel. “Longitudinal
handling characteristics of a tailless gull-wing
aircraft.” 2008. Web. 24 Jan 2021.
Vancouver:
Agenbag D. Longitudinal
handling characteristics of a tailless gull-wing
aircraft. [Internet] [Masters thesis]. University of Pretoria; 2008. [cited 2021 Jan 24].
Available from: http://hdl.handle.net/2263/28011.
Council of Science Editors:
Agenbag D. Longitudinal
handling characteristics of a tailless gull-wing
aircraft. [Masters Thesis]. University of Pretoria; 2008. Available from: http://hdl.handle.net/2263/28011
Brigham Young University
3.
Luke, Mark Elden.
Predicting Drag Polars For Micro Air Vehicles.
Degree: MS, 2003, Brigham Young University
URL: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=1107&context=etd
Drag polars for three Micro Air Vehicles (MAVs) were measured at Reynolds numbers of 70,000, 50,000, 30,000, and 10,000 and compared to predictions generated using the classical approach. The MAVs tested had different configurations and aspect ratios varying from 1.2 to 1.6 and ratios of wetted surface area to planform area from 2.6 to 3.9. A force balance was used to measure the lift and drag on the MAVs at angles of attack ranging from -5 degrees (or -10 degrees) to 10 degrees. The force balance allowed the MAVs to rotate in the pitching axis. The MAV angle of attack was set using an elevator installed on the MAV and controlled using a standard radio control used by RC plane enthusiasts. Uncertainty analysis performed on the data showed the uncertainty for high Reynolds numbers was dominated by velocity uncertainty, and uncertainty for the lower Reynolds numbers was dominated by uncertainty in the force measurements. Agreement between measured and predicted drag polars was good with the measured drag never being more than two times the predicted drag. For the majority of the tests, the drag coefficients followed the expected Reynolds number trend: increasing with decreasing Reynolds number.
Subjects/Keywords: Micro Air Vehicle; MAV; low Reynolds number; drag polar; predicted vs. measured; wind tunnel; force balance; Cfe; equivalent skin friction coefficient; e0; oswald efficiency; CL; minD; lift coefficient; drag coefficient; drag polar prediction; angle of attack; wetted surface area ratio; wing loading; aspect ratio; parasite drag coefficient; drag due to lift; aerodynamics; Mechanical Engineering
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Luke, M. E. (2003). Predicting Drag Polars For Micro Air Vehicles. (Masters Thesis). Brigham Young University. Retrieved from https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=1107&context=etd
Chicago Manual of Style (16th Edition):
Luke, Mark Elden. “Predicting Drag Polars For Micro Air Vehicles.” 2003. Masters Thesis, Brigham Young University. Accessed January 24, 2021.
https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=1107&context=etd.
MLA Handbook (7th Edition):
Luke, Mark Elden. “Predicting Drag Polars For Micro Air Vehicles.” 2003. Web. 24 Jan 2021.
Vancouver:
Luke ME. Predicting Drag Polars For Micro Air Vehicles. [Internet] [Masters thesis]. Brigham Young University; 2003. [cited 2021 Jan 24].
Available from: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=1107&context=etd.
Council of Science Editors:
Luke ME. Predicting Drag Polars For Micro Air Vehicles. [Masters Thesis]. Brigham Young University; 2003. Available from: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=1107&context=etd
. 
Open Access Theses and Dissertations