STABILITY AND CONTROL CHARACTERISTICS OF DOUGLAS MODEL XF4D-1. PART I. LOW SPEED FLYING QUALITIES

1949 ◽  
Author(s):  
JR HUFF ◽  
W. W.
Keyword(s):  
Low Speed ◽  
Stability And Control ◽  
Flying Qualities ◽  
And Control

scholarly journals Conceptual Design, Flying, and Handling Qualities Assessment of a Blended Wing Body (BWB) Aircraft by Using an Engineering Flight Simulator

Aerospace ◽  
2020 ◽  
Vol 7 (5) ◽  
pp. 51 ◽  
Author(s):  
Clayton Humphreys-Jennings ◽  
Ilias Lappas ◽  
Dragos Mihai Sovar
Keyword(s):  
Static Stability ◽  
Flight Simulator ◽  
Handling Qualities ◽  
Stability And Control ◽  
Flying Qualities ◽  
Blended Wing Body ◽  
And Control ◽  
Drag Ratio ◽  
Lift To Drag Ratio ◽  
Mission Profile

The Blended Wing Body (BWB) configuration is considered to have the potential of providing significant advantages when compared to conventional aircraft designs. At the same time, numerous studies have reported that technical challenges exist in many areas of its design, including stability and control. This study aims to create a novel BWB design to test its flying and handling qualities using an engineering flight simulator and as such, to identify potential design solutions which will enhance its controllability and manoeuvrability characteristics. This aircraft is aimed toward the commercial sector with a range of 3000 nautical miles, carrying 200 passengers. The BWB design was flight tested at an engineering flight simulator to first determine its static stability through a standard commercial mission profile, and then to determine its dynamic stability characteristics through standard dynamic modes. Its flying qualities suggested its stability with a static margin of 8.652% of the mean aerodynamic chord (MAC) and consistent response from the pilot input. In addition, the aircraft achieved a maximum lift-to-drag ratio of 28.1; a maximum range of 4,581 nautical miles; zero-lift drag of 0.005; while meeting all the requirements of the dynamic modes.

A Differential Configuration of Split Drag-Rudders with Variable Bias for Directional Control of Flying-Wing

2014 ◽  
Vol 643 ◽  
pp. 54-59 ◽  
Author(s):  
Jahanzeb Rajput ◽  
Wei Guo Zhang ◽  
Xiao Bo Qu
Keyword(s):  
Cfd Simulation ◽  
Angle Of Attack ◽  
Large Angle ◽  
Simple Method ◽  
Low Speed ◽  
Control Efficiency ◽  
Stability And Control ◽  
Directional Stability ◽  
Variable Bias ◽  
And Control

The directional stability and control is crucial for the low-speed flight of a flying-wing aircraft. The split drag-rudders are well known devices used to provide directional stability and control in a flying-wing aircraft. As opposed to conventional rudders, the control efficiency of split drag-rudders is typically low for small deflection-angles and the influence on yawing moment is nonlinear. Such characteristics limit the control capability of split drag-rudders at low speed flight with large angle-of-attack. In this paper, a simple method is presented to improve the control efficiency of split drag-rudders at low speed flight with large angle-of-attack. The method is based on a strictly differential configuration of split drag-rudders which operates around a certain variable bias. The bias can be varied according to different flight conditions in order to achieve desired performance. The CFD simulation results are presented in support of this concept. Results also show that the proposed configuration has linearizing effects on yawing moment vs. deflection curves, which may prove helpful in control system design process. The possible control reversal in yaw at large angle of attack can also be avoided with this method.

scholarly journals Conceptual Design optimization of a Blended Wing Body (BWB) Aircraft Using Flying and Handling Qualities Assessment

2019 ◽  
Author(s):  
Clayton Humphreys-Jennings ◽  
Ilias Lappas ◽  
Dragos Mihai Sovar
Keyword(s):  
Flight Test ◽  
Static Stability ◽  
Flight Simulator ◽  
Handling Qualities ◽  
Stability And Control ◽  
Flying Qualities ◽  
Blended Wing Body ◽  
And Control ◽  
Drag Ratio ◽  
Lift To Drag Ratio

The Blended Wing Body (BWB) configuration is considered to have the potential of providing significant advantages when compared to conventional aircraft designs. At the same time, numerous studies have reported that technical challenges exist in many areas of its design, including stability and control. This study aims to create a novel BWB design to test its flying and handling qualities using an engineering flight simulator and as such, to identify potential design solutions which will enhance its controllability and manoeuvrability characteristics. This aircraft is aimed toward the commercial sector with a range of 3,000 nautical miles, carrying a payload of 20,000kg. In the engineering flight simulator a flight test was undertaken; first, to determine the BWB design’s static stability through a standard commercial mission profile, and then to determine its dynamic stability characteristics through standard dynamic modes. Its flying qualities suggested its stability with a static margin of 8.652% of the Mean Aerodynamic Chord (MAC) and consistent response from the pilot input. In addition, the aircraft achieved a maximum lift-to-drag ratio of 28.1; a maximum range of 4,581 nautical miles; zero-lift drag of 0.005; and meeting all the requirements of the dynamic modes.

scholarly journals GROUND BASED VARIABLE STABILITY FLIGHT SIMULATOR

Aviation ◽  
2021 ◽  
Vol 25 (1) ◽  
pp. 22-34
Author(s):  
Kamali Chandrasekaran ◽  
Vijeesh Theningaledathil ◽  
Archana Hebbar
Keyword(s):  
Autonomous Navigation ◽  
Optimization Techniques ◽  
Flight Mechanics ◽  
Pilot Training ◽  
Flight Simulator ◽  
Fighter Aircraft ◽  
Training Requirements ◽  
Stability And Control ◽  
Flying Qualities ◽  
And Control

This paper discusses the development of a ground based variable stability flight simulator. The simulator is designed to meet the pilot training requirements on flying qualities. Such a requirement arose from a premier Flight-Testing School of the Indian Air Force. The simulator also provides a platform for researchers and aerospace students to understand aircraft dynamics, conduct studies on aircraft configuration design, flight mechanics, guidance & control and to evaluate autonomous navigation algorithms. The aircraft model is built using open source data. The simulator is strengthened with optimization techniques to configure variable aircraft stability and control characteristics to fly and evaluate the various aspects of flying qualities. The methodology is evaluated through a series of engineer and pilot-in-the-loop simulations for varying aircraft stability conditions. The tasks chosen are the proven CAT A HUD tracking tasks. The simulator is also reconfigurable to host an augmented fighter aircraft that can be evaluated by the test pilot team for the functional integrity as a fly-through model.

Discontinuous Dynamics and Bifurcation for Morphing Aircraft Switching on the Velocity Boundary

2020 ◽  
Author(s):  
Jianzhe Huang ◽  
Xilin Fu ◽  
Zhongliang Jing ◽  
Siyuan Xing
Keyword(s):  
High Speed ◽  
Critical Speed ◽  
Point Of View ◽  
Intermediate Structure ◽  
Morphing Aircraft ◽  
Low Speed ◽  
Stability And Control ◽  
System A ◽  
The Moment ◽  
And Control

Abstract The concept of morphing aircraft was developed many decades ago, and many researches on the morphing aircraft such as stability and control have been published. As the point of view of the dynamic theory, the dynamic system of the morphing aircraft is consisted with multiple subsystems, and each subsystem represents the morphing aircraft with specific structure to fulfill a particular flight task. The switching process from one structure to another for such a morphing aircraft is considered to be smooth and stable, and the switching time is also assumed to be infinitely small. In this paper, a morphing aircraft with high-speed structure, intermediate-structure and low-speed structure is studied. Such a morphing aircraft is set to switch between high-speed structure and low-speed structure when the speed of aircraft arrives a preset critical speed, and the analytical conditions for switchability is developed. If such a morphing aircraft cannot switch to a low-speed structure or high-speed structure at the moment when it arrives the critical speed, it will switch to an intermediate-structure and control to keep the speed remain constant. The analytical conditions for onset and vanish of such a morphing aircraft switching to the intermediate-structure are also provided. Mapping structure is defined to describe the periodic motions of such a morphing aircraft. The bifurcation scenario is calculated to show the complexity of such a hybrid dynamical system. A periodic motion is given to illustrate the flow of such a morphing aircraft switching on the velocity boundary.

Effects of Aircraft Tail Configurations on Sensitivity to Yaw Disturbances

2014 ◽  
Vol 629 ◽  
pp. 197-201 ◽  
Author(s):  
Nur Amalina Musa ◽  
S. Mansor ◽  
Airi Ali ◽  
Wan Zaidi Wan Omar ◽  
Ainullotfi Abdul Latif ◽  
...  
Keyword(s):  
Wind Tunnel ◽  
Wind Tunnel Test ◽  
Aerodynamic Characteristics ◽  
Low Speed ◽  
Stability And Control ◽  
Directional Stability ◽  
And Control ◽  
Low Speed Wind Tunnel ◽  
Yaw Moment ◽  
Made In

A wind tunnel test was conducted to compare the characteristics of low speed stability and control for aircraft with conventional tail and V-tail configurations. Comparison was made in terms of static directional stability at selected test speed of 40 m/s, which corresponds to Reynolds number of 0.1622 x 106 based on the chord. Three types of simplified tail-only model were tested in Universiti Teknologi Malaysia's Low Speed Wind Tunnel (UTM-LST). Results show that the V-tail configuration greatly affects the aerodynamic characteristics in directional stability as the side force and yaw moment tends to vary linearly with yaw angles up to 25 degrees, compared to conventional tail that has linear characteristics up to only 10 degrees yaw

Design and Fabrication of a Dual Rotor-Embedded Wing Vertical Take-Off and Landing Unmanned Aerial Vehicle

2020 ◽  
Vol 09 (01) ◽  
pp. 45-63
Author(s):  
Seng Man Wong ◽  
Hann Woei Ho ◽  
Mohd Zulkifly Abdullah
Keyword(s):  
Low Cost ◽  
Estimation Method ◽  
Design Parameters ◽  
Stability And Control ◽  
Flying Qualities ◽  
Vtol Uav ◽  
Final Design ◽  
Aerial Vehicle ◽  
And Control ◽  
Drag Ratio

The interest in building hybrid Unmanned Aerial Vehicles (UAVs) is increasing intensively due to its capability to perform Vertical Take-Off and Landing (VTOL), in addition to forward flight. With this capability, the hybrid UAVs are highly on demand in various industries. In this paper, a fixed-wing VTOL UAV with a novel configuration of a dual rotor-embedded wing was designed and developed. The methodology used in the design process adopted the traditional sizing and aerodynamic estimation method with advanced computational simulations and estimation approaches. The design was determined based on a thorough analysis of weight contribution, aerodynamics, propulsion, and stability and control. The results show that the UAV’s preliminary design has successfully reached a total weight of 1.318 kg, achieved a high lift-to-drag ratio of approximately 4, and ensured stable flights with Level 1 flying qualities. A fixed-wing VTOL prototype was developed and fabricated based on the final design parameters using a low-cost hand lay-up process.

The Stability and Control of Slender Delta Aircraft

1968 ◽  
Vol 40 (6) ◽  
pp. 22-29 ◽  
Keyword(s):  
Common Property ◽  
Transport Aircraft ◽  
Low Speed ◽  
Supersonic Aircraft ◽  
Stability And Control ◽  
Great Body ◽  
The Common ◽  
The Stability ◽  
And Control

The common property of being able to travel faster than sound does not in general confer on aircraft any other similarities of shape or form. Thus supersonic aircraft have no great body of low speed behaviour in common, consequently in order to limit the discussion the following relates to a particular type of supersonic aircraft — namely large transport aircraft of slender delta form.

Sign in / Sign up

Export Citation Format

Share Document