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Airdrop operation has become an important transportation mode due to its mobility and rapidity and mission planning is one of the critical steps in the preparation of an airdrop operation. The purpose of this paper is to propose an efficient mission planning method for airdrop operation using multiple vehicles.

A hierarchical mission planning method is proposed. According to the objectives of the action, the mission planning is divided into three planning levels to form the hierarchical structure and the constraints are distributed among them. By doing so, the proposed approach converts the original mission planning problem to a constrained optimization problem, which is solvable using existing mathematical methods.

On the basis of analysis, the mathematic models of three planning levels are established. Each level has its own optimization objective, taking part of constraints into account. The integrated mission scheme had been obtained step by step.

This paper systematically tackles the complicated multiple vehicles airdrop mission planning problem, and it provides a platform for optimizing the outcomes. The mathematical models established in this paper could apply in a variety of more complex mission scenarios.

This paper fulfils an urgent need to study how the advantages of airdrop operation can be maximized through planning airdrop mission schemes carefully.

This paper aims to investigate the addition of airdrop capability to a commuter aircraft and its consequences on the reversible flight control system.

Airdrop was modeled to include its effect on aerodynamics and flight control system. A mathematical model was also developed for the reversible longitudinal flight control system of a regional commuter aircraft using the available geometry, mass property and kinematics. The model was incorporated into a general multi‐body dynamics code and validated using existing manufacturer's data which included recorded data from flight. The airdrop simulation results showed that the flight control system is affected in two steps. In the first step, the movement of the load required a forward force by the pilot. In this step, the elevator power was a key factor and had to be increased to allow the pilot to keep the aircraft in trim position during the airdrop. In the second step, a sudden forward shift of centre of gravity required an abrupt change in the direction of applied force. The maximum allowable force and control column movement had to be checked. In the case under study, they did not impose any difficulty.

The result showed that a special consideration had to be taken into account when an aircraft with reversible flight control system was to be used for airdrop mission.

This paper investigates the behaviour of a reversible flight control system during airdrop operation through analysis and simulation.

During low altitude airdrop operations, the heavy cargo moving inside and the sudden dropping out exert serious threats on the aircraft safety and mission performance. This paper aims to propose an efficient flight control method for the airdrop operations.

A novel controller which combines feedback linearization with nonlinear integral sliding mode control is proposed. The aircraft airdrop model is decoupled and linearized by using the feedback linearization technique. On this basis, an integral sliding mode controller is designed to stabilize the speed and pitch attitude of the aircraft. In the sliding manifold, one class of nonlinear functions with the property of “smaller errors correspond to bigger gains and bigger errors correspond to saturated gains” is introduced to form the integral term; thus, the overcompensation of the integral term to big errors is omitted, and the dynamic response performance is improved. Lyapunov-based stability analysis shows that the controller could completely reject model uncertainties by choosing proper controller parameters.

The flight control system with strong robustness could meet the low altitude airdrop indexes in the maximum weight cargo airdrop task.

This paper fulfils an urgent need to study how to control the aircraft to guarantee mission performance and flight safety during the low altitude airdrop operations.

The purpose of this paper is to model the aircraft-cargo’s coupling dynamics during ultra-low altitude heavy cargo airdrop and to design the aircraft’s robust flight control law counteracting its aerodynamic coefficients perturbation induced by ground effect and the disturbance from the sliding cargo inside.

Aircraft-cargo system coupling dynamics model in vertical plane is derived using the Kane method. Trimmed point is calculated when the cargo fixed in the cabin and then the approximate linearized motion equation of the aircraft upon it is derived. The robust stability and robust H_∞ optimal disturbance restraint flight control law are designed countering the aircraft’s aerodynamic coefficients perturbation and the disturbance moment, respectively.

Numerical simulation shows the effectiveness of the proposed control law with elevator deflection as a unique control input.

The model derived and control law designed in the paper can be applied to heavy cargo airdrop integrated design and relevant parameters choice.

The dynamics model derived is closed, namely, the model can be called in numerical simulation free of assuming the values of parachute’s extraction force or cargo’s relative sliding acceleration or velocity as seen in many literatures. The modeling is simplified using Kane method rather than Newton’s laws. The robust control law proposed is effective in guaranteeing the aircraft’s flight stability and disturbance restraint performance in the presence of aerodynamic coefficients perturbation.

The purpose of this paper is to improve the design of a solid square canopy of a parachute. The design improvements are brought out by providing minor slits in the canopy area. Proper designing of the parachute was carried out using theoretical investigation coupled with experimentation. This parachute is designed for launch of sonobuoy from fixed wing aircraft.

Literature review was carried out on the design of such parachutes for the launch of a sonobuoy from a high altitude to the water entry. Computational fluid dynamics (CFD) analysis provided the value of the coefficient of drag for the slit-cut square canopy parachute, with and without sonobuoy for different lengths of the slit. Besides the theoretical investigation, experimentation was also carried out to validate the design.

The experimentation was carried out on 58 and 75 gsm fabric canopies with the slit edge plain-cut with thermally sealed edges, stitched and strengthened. In the case of plain-cut slits on the canopy made of 75 gsm fabric, no tearing of the slit edge was observed in dynamic and flight tests.

The present work has been carried out considering various assumptions and limited trial data specific to precision drop of 9 kg payload. The work can be adopted for bigger parachute for dropping of higher payloads.

Lab strength test, track dynamic and flight trials were conducted to acquire useful data for the present analysis. Besides the theoretical investigations and CFD analysis inherently based on numerous assumptions, experimentation was carried out as the sonobuoy deployment conditions are full of uncertainty. Dynamic and airdrop tests were conducted for this reason to determine design changes in the slits, both at the material level and on improvisations.

To analyze and draw conclusions from the “Framework for ‘Investment Contract’ Analysis of Digital Assets” (the “Framework”), released by the US Securities and Exchange Commission (the “SEC”) on April 3, 2019, and the SEC’s corresponding no-action letter to TurnKey Jet, Inc. (“TKJ”), which is the SEC’s first no-action letter publicly agreeing with the view that the digital asset described therein is not a security.

Explains how the Framework assists market participants in analyzing whether a digital asset is a security, by applying the Howey factors for identifying an investment contract. Discusses the SEC’s TKJ Letter, highlighting the factors the SEC emphasized in its analysis of the Framework.

While largely reiterating prior guidance, the Framework provides a helpful overview of the SEC’s views on when a digital asset is a security and how to properly analyze the prongs of Howey with respect to digital assets. The Framework also leaves certain important questions unanswered, including, for example, whether digital assets distributed by means of a so-called “Airdrop” are securities under the Framework, and the extent to which the Framework is meant to interact with digital assets that were issued or otherwise operate on platforms that are primarily overseas.

Expert guidance from lawyers with broad experience in financial services, securities, investment funds, derivatives, and digital assets regulation and compliance.

THE Belfast was designed and built to a specification for a long range strategic aircraft suitable for carrying heavy and bulky items of freight. The ability to airdrop supplies, combined with structural advantages, led to the choice of rear access to the freight hold; utilisation of part of the freight door as a loading ramp leads to independence of ground based freight handling equipment. The rear fuselage was up‐swept in order to provide ample head‐room for cargo on the ramp. To minimise this upsweep and also to facilitate handling of heavy loads, a low angle of inclination of the ramp is necessary. This led to a low freight floor height in relation to the ground, and to flattening of the rear fuselage undersurface. These features are illustrated in FIG. 1 which depicts the unloading of an Abbott self propelled gun carrier.

This chapter discusses legal considerations relating to digital assets. The legal aspects of tokenized and non-tokenized assets are evolving. Although some states have enacted specific laws or regulations for digital assets, Congress and federal agencies have been slower to craft specific rules and regulations for such assets. As a result, regulators, such as the Securities and Exchange Commission, Commodity Futures Trading Commission, and Internal Revenue Service, and market participants must apply existing guidance to digital assets. This chapter examines applying specific aspects of federal securities and tax law to digital assets. It also discusses general business law considerations for blockchain and cyber enterprises. The discussion of state law applications centers on the New York Virtual Currency License and Wyoming and Delaware crypto initiatives. This chapter does not provide a comprehensive review of all legal issues related to cryptocurrency. Each legal issue about cryptocurrency is complex and requires separate analyses.