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The purpose of this paper is to develop a directional and roll control system for unmanned combat air vehicle (UCAV) automatic takeoff roll, with the objective of keeping the UCAV along the runway centerline and keeping the wings level, especially when there is a crosswind.

The nonlinear model of the UCAV during takeoff roll is established. The model is linearized about the lateral‐directional equilibrium point at different forward speeds. The approximate directional model and roll model are extracted using time‐scale decomposition technique. Then the directional control law and roll control law are developed using gain scheduling approach. Nose wheel steering, differential brake and rudder are used as the primary directional control device at low, medium and high speeds, respectively, according to both the qualitative and quantitative analysis of their control effectiveness at different speeds. A priority matrix is developed to determine the secondary control device which is used if the primary control device fails, thus the directional control system can have a certain degree of fault tolerance.

This work developed the directional control law and roll control law by using gain scheduling approach. Experimental results verified that the developed directional and roll control system has high robustness and satisfactory fault tolerance: it can guarantee a safe takeoff under a 50 ft/sec crosswind, even if one directional control device fails, which satisfies the relevant criteria in MIL‐HDBK‐1797.

The directional and roll control system developed can be easily applied to practice and can steer the UCAV during takeoff roll safely, which will considerably increase the autonomy of the UCAV.

The paper shows how time‐scale decomposition technique is employed to extract the approximate directional model and roll model, which simplifies model analysis and control law design. A fault‐tolerant directional control system is designed to improve safety during takeoff.

The DC‐9 Super 80 will be delivered with advanced avionics in early 1980. This paper discusses from the aircraft manufacturer's point of view the avionics system architecture, its digital implementation, and some hardware details of most major system elements. New operational features are discussed including Category IIIa autoland, some new autopilot and autothrottle cruise modes, a head‐up display system, and a “hot on‐board spare” flight guidance computer. Finally, some of the advantages of the digital system over analog systems are noted.

We investigate product innovation by a cohort of entrants who use technology that eventually suffers disruption. We concentrate on two types of entrants – those with and those without relevant prior experience in the disrupted technology. Using the industrial robotics industry as the context of our study, we explore product innovation using disrupted technology during two time periods: the first prior to sales takeoff of the disruptive products and the second subsequent to takeoff. We find that the two types of entrants did not differ in product innovation prior to takeoff, but firms with prior experience in the disrupted technology manufactured more innovative products subsequent to the sales takeoff of disruptive products. Our research underscores that the boundary conditions of the utility of prior experience is more nuanced than that which literature suggests – it affects product innovation only in the post-sales takeoff period when the demand uncertainties are relatively low. Our findings also suggest that the boundary conditions of Christensen’s thesis are narrower than predicted by prior literature.

The purpose of this paper is to demonstrate the uncontrolled vertical takeoff of an insect-mimicking flapping-wing micro air vehicle (FW-MAV) of 12.5 cm wing span with a body weight of 7.36 g after installing batteries and power control.

The forces were measured using a load cell and estimated by the unsteady blade element theory (UBET), which is based on full three-dimensional wing kinematics. In addition, the mean aerodynamic force center (AC) was determined based on the UBET calculations using the measured wing kinematics.

The wing flapping frequency can reach to 43 Hz at the flapping angle of 150°. By flapping wings at a frequency of 34 Hz, the FW-MAV can produce enough thrust to over its own weight. For this condition, the difference between the estimated and average measured vertical forces was about 7.3 percent with respect to the estimated force. All parts for the FW-MAV were integrated such that the distance between the mean AC and the center of gravity is close to zero. In this manner, pitching moment generation was prevented to facilitate stable vertical takeoff. An uncontrolled takeoff test successfully demonstrated that the FW-MAV possesses initial pitching stability for takeoff.

This work has successfully demonstrated an insect-mimicking flapping-wing MAV that can stably takeoff with initial stability.

The successful culmination of missions based on Unmanned Aerial Vehicles (UAV) can be measured with two main parameters: (1) successful mission completion: all objectives of the mission (e.g., maneuvering and navigation, reconnaissance and targeting or search and rescue, and return) were accomplished and (2) safety: no damage to the vehicle and no fatalities or injuries to any human were sustained throughout the mission. Automation of the UAV's control and operations increasingly becomes a determining factor in successful mission completion and increased safety. However, in this day and age of automatically launched and retrieved swarms of UAVs, the human operator still has a critical role. Human-controlled UAVs will persist for a long time and human error is a factor that still needs addressing in the age of automation. Even a single person, who has flown radio-controlled model aircraft as a hobby since childhood, can still cause the crash of an expensive UAV in a matter of seconds. Moreover, there are aspects of human error in UAV control that can have important implications to the implementation of automation and to keeping the human operator in the control loop.

THE PRIMARY FUNCTIONAL SYSTEMS — hydraulic, electrical electronic, environmental control, and auxiliary power systems — are separated into localised centres to allow simultaneous inspection and maintenance with minimum congestion between ground personnel and equipment. Other factors considered in the design layout of the service centres were the distribution of components in each system, aircraft weight and balance, component size, area environment and accessibility. Isolation from the hazards of possible engine turbine‐blade and wheel tyre failures was another important consideration. Standardisation and interchangeability of equipment within the L1011 aircraft, and among other transports operating in the same time period also influenced the functional system design.

use of tools. An additional two wheels make this truck very sturdy and able to carry a variety of different loads without having to change the truck.

Making their first Farnborough appearance were two Grumman types among the many international newcomers. The E‐2C Hawkeye was in the static park equipped with five tons of electronic equipment that is capable of simultaneously detecting hundreds of targets over land or sea and guiding interceptors on to these targets. The Grumman F‐14A Tomcat two seat swing‐wing carrier‐based air superiority fighter gave daily flight demonstrations which hinted at its versatility. It is equipped with the AW‐9 weapons control system which is claimed to have exceptional detection ranges, standoff firing capabilities and attack modes. The Tomcat and Hawkeye are complementary and this capability was emphasised by the manufacturers, since both are in service with the US Navy and operate as a team with a high security voice and data communications system.

The Seventh MD‐11 has flown — Wearing the colors of Delta Air Lines, the big McDonnell Douglas trijet accomplished a flawless first takeoff on September 5, 1990, from Long Beach Airport. The aircraft is the fifth trijet to join the MD‐11 flight test program in Yuma, Arizona, for evaluating flight crew workloads in simulated flight operations and testing the function and reliability of interior components

The Paris/Le Bourget International Air and Space Show is the world's oldest international show and is of considerable importance. It will have 548 exhibitors from 23 countries and there will be 165,000 square metres of display area — with 10,000 square metres for the out‐door static exhibits. The numbers of chalets is to be increased by 55.