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The purpose of this paper is to describe the effects of characteristic geometric parameters on parafoil aerodynamic performance by using computational fluid dynamics (CFD) technique.

The main characteristic geometric parameters cover the planform geometry, arc‐anhedral angle, basic airfoil and leading‐edge cut. By using the CFD technique, a large number of numerical parafoil models with different geometric parameters are developed to study the correlations between these parameters and parafoil aerodynamic performance.

The CFD technique is feasible and effective to study the effects of characteristic geometric parameters on parafoil aerodynamic performance in three‐dimensional (3‐D) flowfield condition. The planform geometry can affect the aerodynamic performance obviously. An increase in arc‐anhedral angle decreases the lift of a parafoil but has little effect on lift‐drag ratio. The model with smaller leading‐edge radius and thinner thickness of parafoil section achieves larger lift‐drag ratio. The leading‐edge cut has little effect on lift but increase drag dramatically; meanwhile, its effect on flowfield is confined to the nearby region of leading edge.

The presented 3‐D numerical simulation results of parafoil models are shown to have good agreement with the tunnel test data in general trend; meanwhile, considering its relatively low‐cost, the CFD method could be further used to predict coefficients in pre‐research or at non‐experimental conditions.

The paper can form the foundation of further studies on parafoil aerodynamic performance with different geometric parameters.

To demonstrate proof‐of‐concept of the Griffon man‐portable hybrid unmanned ground vehicle/unmanned aerial vehicle (UGV/UAV) based on the iRobot PackBot we developed the Griffon air mobility system consisting of a gasoline‐powered propeller engine, a steerable parafoil, and a radio‐controlled servo system. We integrated the AMS with a PackBot prototype, and we conducted ground and flight tests to validate this concept. The Griffon prototype was capable of remote‐controlled flight, take‐off, and landing. The Griffon achieved speeds of over 20 mph and altitudes of up to 200 feet. We demonstrated the feasibility of developing a man‐portable hybrid UGV/UAV. Future work may explore the possibilities for teleoperated, semi‐autonomous, and fully autonomous control using the Griffon concept. The parafoil wing limits the usability of this vehicle in windy conditions, but this could be addressed using a lightweight fixed wing instead. Man‐portable hybrid UGV/UAVs may be used by the military to perform reconnaissance and strike missions in urban environments, and by civilian teams to conduct search‐and‐rescue operations in hazardous terrain. This research provides the first demonstration of a man‐portable unmanned vehicle capable of both flight and ground locomotion, and it does so using a combat‐tested UGV platform.

Parachute recovery systems are described from a systems perspective. Parachute recovery is particularly suited to tactical fixed wing UAV systems that require a high degree of mobility by allowing air vehicle recovery onto unprepared terrain. The descent environment is described, and the impact of wind on recovery is considered. The relative merits of cruciform, round and parafoil canopies are assessed, taking three real‐world systems as design examples. Throughout, design considerations are approached from a systems perspective, with a view to producing safe, autonomous and accurate recovery systems.

This paper summarises the work done in the development of a flight simulation software package called AEROSIM by Rapid Data Ltd. The objective of this work is to use simulation and analysis facilities to reduce the development time and costs involved in aerospace vehicle modelling by providing a generic and extendible model combined with a user‐friendly graphical interface. Large parts of six degrees of freedom simulation models are common to all vehicles and AEROSIM exploits this by providing these parts ready written and developed. As a result the users have only to concern themselves with the specific details of their vehicle. AEROSIM generates a non‐linear model for aircraft, missile, airship, parafoil and underwater vehicle simulation.

Fault detection, isolation and reconfiguration of the flight control system is an important problem to obtain healthy flight. This paper aims to propose an integrated approach for aircraft fault-tolerant control.

The integrated structure includes a Kalman filter to obtain without noise, a full order observer for sensor fault detection, a GOS (generalized observer scheme) for sensor fault isolation and a fuzzy controller to reconfigure of the healthy sensor. This combination is simulated using the state space model of a lateral flight control system in case of disturbance and under sensor fault scenario.

Using a dedicated observer scheme, the detection and time of sensor fault are correct, but the sensor fault isolation is evaluated incorrectly while the faulty sensor is isolated correctly using GOS. The simulation results show that the suggested approach works affectively for sensor faults with disturbance.

This paper proposes an integrated approach for aircraft fault-tolerant control. Under this framework, three units are designed, one is Kalman filter for filtering and the other is GOS for sensor fault isolation and another is fuzzy logic for reconfiguration. An integrated approach is sensitive to faults that have disturbances. The simulation results show the proposed integrated approach can be used for any linear system.

The purpose of this paper is to suggest and research a method for passenger life‐saving in a badly damaged aircraft scenario.

The small parachute, brake rocket and inflatable pillow are used for research and design. Theory of braking is offered, researched, developed and the brake possibilities are computed.

It is shown here that previous works which have proposed using only parachutes are useless because these failed to consider the likely overload of the parachute jerk stress (at the moment of parachute release) and the impact of aircraft on the Earth's surface. These jerks and impacts destroy aircraft and kill passengers.

This method is limited by an additional weight of the brake system.

Offered is a new method for saving passenger lives in any catastrophic situation, including total failure of aircraft control, extreme damage and loss aircraft wings, tail, breakdown all propelling engines, etc.

Offered is a connected series of related technical innovations which overcome obvious difficulties and allow for a soft, near zero speed landing in any topographically suitable place, allowing potential to save aircraft. This method may be applied to all existing airplanes and increases their weight only about 1.5/2.5 per cent. Also, the method may be used for vertically landing the already built aircraft, for example, when any runway is damaged or would become overloaded.

The purpose of this review paper is to outline the parachute materials and its behavior. To enhance parachute life, it is highly desirable to consider the commercial angle for any parachute manufacturing industry and its components under varying operational conditions. Hence, the knowledge of various textile materials and operational conditions which contributes the parachute strength and durability will be helpful for industries/researchers.

This section is not applicable for a review paper.

Parachute is a material used in numerous real-time applications such as man-drop, cargo delivery, aircraft recovery and aircraft decelerator which drastically reduces human efforts and time. However, each application requires a unique design and fabric selection to achieve the area of drag needed and the terminal velocity of the parachute material while in flight. For designing a man-drop parachute, the most critical parameters are weight and strength which must be considered during manufacturing. The army person uses the man-drop parachute, which must be as light as possible.

This paper is an original review work and will be helpful for parachute manufacturers/researchers to enhance the life of parachutes with improved functionality.