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The growing need for an efficient worldwide airspace system management, generated by an increasing traffic load, requires new capabilities for air-ground data communication technologies. In order to cope with these requirements, the Federal Aviation Administration (FAA), EUROCONTROL, and the International Civil Aviation Organization (ICAO) have jointly made specific recommendations for candidate technologies for the airport surface communication network. In the SESAR project, the Aeronautical Mobile Airport Communication System (AeroMACS) technology is being developed in such a way to provide next generation broadband and wireless data communications for airport surface applications (i.e. Air Traffic Control ? ATC, Airline Operational Communications ? AOC, and surface vehicles services).

Electroimpact Automatic Fiber Placement (AFP) machines lay-up composite parts by accurately placing carbon fiber tow (strips of impregnated carbon fiber) on a mould. In order to achieve high accuracy at high speeds, the processes of feeding and cutting tows must be tuned. Historically, the tuning has been a time-consuming, manual process. This paper will present a methodology to replace manual measurements with an automated laser, improve measurement speed by an order of magnitude, improve accuracy from +/? 0.020? (manual) to +/? 0.015? (laser), and eliminate human error. Presenter Joshua Cemenska, Electroimpact Inc.

This technical paper collection features 15 papers covering electrification of the commercial vehicle, techniques for efficiency and reliability; developments in sensors; model based design and embedded software development; heavy duty electronic technology; autonomous vehicles; electronic control module development and test; and vehicle structure.

This document establishes the minimum criteria for effective training of air carrier and contractor personnel to deice/anti-ice aircraft to ensure the safe operation of aircraft during ground icing conditions. Appendix D specifies guidelines for particular airplane models.

Abstract A novel use of state estimation methods as initial input for a landing response analysis is proposed in this work. Six degrees of freedom (DOF) non-linear landing response model is conceived by considering longitudinal dynamics of aircraft as a rigid body with heave-and-pitch motions coupled onto a bicycle landing gear † arrangement. The DOF for each landing gear consist of vertical and longitudinal motions of un-sprung mass, considering strut bending flexibility. The measurement data for state estimation is obtained for three landing cases using non-linear flight mechanics model interfaced with pilot-in-loop simulation. State estimation methods such as Upper Diagonal Adaptive Extended Kalman Filter (UD-AEKF) with fuzzy-based adaptive tuning and Un-scented Kalman Filter (UKF) were adapted for landing maneuver problem. On the basis of estimation error metrics, aircraft state from UKF is considered during onset of touchdown.

Abstract The main focus of this article is the online estimation of the terminal airspace sector capacity from the Air Traffic Controller 0ATC) dynamical neural model using Neural Partial Differentiation (NPD) with permissible safe separation and affordable workload. For this purpose, a primarily neural model of a multi-input-single-output (MISO) ATC dynamical system is established, and the NPD method is used to estimate the model parameters from the experimental data. These estimated parameters have a less relative standard deviation, and hence the model validation results show that the predicted neural model response is well matched with the intervention of the ATC workload. Moreover, the proposed neural network-based approach works well with the experimental data online as it does not require the initial values of model parameters, which are unknown in practice.

Abstract A flight envelope for aircraft performance in the vertical plane illustrates the performance limitations on the aircraft, usually indicating the minimum and maximum airspeeds at a given altitude, the airspeeds for maximum rate of climb and maximum angle of climb at a given altitude, and the maximum altitude or absolute ceiling of the aircraft. This study outlines the procedure for constructing a vertical-plane flight performance aircraft for an aircraft with a fixed-pitch propeller, which involves additional complexities due to the variable propeller efficiency. The propeller performance, engine power, and drag polar models are described, as is the computational procedure. Envelopes for the flight performance in the vertical plane are presented for a particular remotely-piloted aircraft at different take-off weights.

This document is intended to explain, in detail, the rationale behind the features and functions of the AS4074, Linear, Token-passing, Bus (LTPB). The discussions also address the considerations which a system designer should take into account when designing a system using this bus. Other information can be found in these related documents: AIR4271 - Handbook of System Data Communication AS4290 - Validation Test Plan for AS4074

This document is intended to explain, in detail, the rationale behind the features and functions of the AS4074, Linear, Token-passing, Bus (LTPB). The discussions also address the considerations which a system designer should take into account when designing a system using this bus. Other information can be found in these related documents:

The C-17 airplane operates in some of the most challenging environments in the world including semi prepared runway operations (SPRO). Typical semi-prepared runways are composed of a compacted soil aggregate of sand, silt, gravel, and rocks. When the airplane lands or takes off from a semi-prepared runway, debris, including sand, gravel, rocks and, mud is kicked up from the nose landing gear (NLG) and the main landing gear (MLG) tires. As the airplane accelerates to takeoff or decelerates from landing touchdown, this airborne debris impacts the underbelly and any component mounted on the underbelly. The result is the erosion of the protective surface coating and damage to systems that protrude below the fuselage into the debris path. The financial burden caused by SPRO damage is significant due to maintenance costs, spares costs and Non-Mission Capable (NMC) time.

The air traffic demand on the US national airspace frequently exceeds its available capacity. In current operations, the Air Traffic Service Provider designs and implements air traffic management initiatives with minimal interaction with the airlines. NASA and its partners have developed a new collaborative air traffic flow management concept of operations that involves the users of the airspace to a greater degree. In this paper, we describe an agent-based simulation of the new concept of operations and our planned experimentation to determine if the new concept of operations will lead to better utilization of the national airspace.

The commercial turbofan trend of increasing bypass ratio and decreasing fan pressure ratio has seen its latest market entry in Pratt & Whitney's PurePower™ product line, which will power regional aircraft for the Bombardier and Mitsubishi corporations, starting in 2013. The high-bypass-ratio, low-fan-pressure-ratio trend, which is aimed at diminishing noise while increasing propulsive efficiency, combines with contemporary business factors including the escalating cost of testing and limited availability of simulated altitude test sites to pose formidable challenges for engine certification and performance validation. Most fundamentally, high bypass ratio and low fan pressure ratio drive increased gross-to-net thrust ratio and decreased fan temperature rise, magnifying by a factor of two or more the sensitivity of in-flight thrust and low spool efficiency to errors of measurement and assumption, i.e., physical modeling.

After the turn of the century, growing social attention has been paid to environmental concerns, especially the reduction of greenhouse gas emissions and it comes down to a personal daily life concern which will affect the purchasing decision of vehicles in the future. Among all the sources of greenhouse gas emissions, the transportation industry is the primary target of reduction and almost every automotive company pours unprecedented amounts of money to reengineer the vehicle technologies for better fuel efficiency and reduced CO2 emission. Besides those efforts paid for sheer improvements of genuine vehicle technologies, NISSAN testified that “connectivity” with outside servers contributed a lot to reduce fuel consumption, thus the less emission of GHG, with two major factors; 1. detouring the traffic congestions with the support of probe-based real-time traffic information and 2. providing Eco-driving advices for the better driving behavior to prompt the better usage of energy.

When the demand for either a region of airspace or an airport approaches or exceeds the available capacity, miles-in-trail (MIT) restrictions are the most frequently issued traffic management initiatives (TMIs) that are used to mitigate these imbalances. Miles-in-trail operations require aircraft in a traffic stream to meet a specific inter-aircraft separation in exchange for maintaining a safe and orderly flow within the stream. This stream of aircraft can be departing an airport, over a common fix, through a sector, on a specific route or arriving at an airport. This study begins by providing a high-level overview of the distribution and causes of arrival MIT restrictions for the top ten airports in the United States. This is followed by an in-depth analysis of the frequency, duration and cause of MIT restrictions impacting the Hartsfield-Jackson Atlanta International Airport (ATL) from 2009 through 2011.

Performance penalties associated with infrared (IR)-signature suppression (IRSS), e.g., increased engine back pressure, weight, drag, cost, and complexity, can shift the engine operating point to higher combustion temperatures. Extra weight degrades aircraft flight performance in terms of reduced range, higher length needed for takeoff, reduced maneuverability, etc. Lift-induced drag penalty due to increased weight shifts the aircraft gas turbine engine operating point to a higher combustion temperature. But the divergent section of the convergent-divergent (C-D) nozzle gives the extra thrust up to optimal flow expansion, which more than compensates the increased lift-induced drag corresponding to its weight. Thus, for the same thrust, an engine with a C-D nozzle operates at a lower combustion temperature than with a convergent nozzle.

Fault-tolerance in commercial aircraft applications is typically achieved by redundancy. In such redundant systems the primary component is checked before the start of a flight to see if it operates correctly. The aircraft will not take off unless the primary is functioning. Airplane manufacturers must certify the airplane systems to be safe for flight. One means of safety certification is by safety analysis which shows that the probability of failure in a typical flight is bounded. The probability bound requirement for a system is based on the criticality of system failure. Usually backup components are checked at intervals that span multiple flights. The first backup may be checked more frequently than the second or higher levels. This leads to flights where the system may have latent faults in the backup components. The probability of failure in such cases varies from flight to flight due to the different exposure times for components in the system.

Aviation safety is one of the key focus areas of the aerospace industry as it involves safety of passengers, crew, assets etc. Due to advancements in technology, aviation safety has reached to safest levels compared to last few decades. In spite of declining trends in in-air accident rate, ground accidents are increasing due to ever increasing air traffic and human factors in the airport. Majority of the accidents occur during initial and final phases of the flight. Rapid increase in air traffic would pose challenge in ensuring safety and best utilization of Airports, Airspace and assets. In current scenario multiple systems like Runway Debris Monitoring System, Runway Incursion Detection System, Obstacle avoidance system and Traffic Collision Avoidance System are used for collision prediction and alerting in airport environment. However these approaches are standalone in nature and have limitations in coverage, performance and are dependent on onboard equipment.

This document contains guidance for using SAE publications, AS4112 through AS4117 (MIL-STD-1553 related Test Plans). Included herein are the referenced test plan paragraphs numbers and titles, the purpose of the test, the associated MIL-STD-1553 paragraph, commentary concerning test methods and rationale, and instrumentation requirements.

This document covers recommendations for the application of existing qualified and approved in-service fixed wing aircraft tires, wheels and brakes to military and commercial rotorcraft. NOTE: This document does not address the use of radial tires due to insufficient data to support their approved use on rotorcraft, see paragraph 4.3.14 for specific impact on ground resonance.