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This paper is based on the results of 50 pedestrian cadaver tests in which the lower limbs injuries were carefully analyzed. The leg injury distribution, the consequences of these injuries will be evaluated through the analysis of equivalent injuries sustained by pedestrian in traffic accidents. These injuries are of several types and involve all biological tissues of lower limbs. We propose a classification of these injuries according to their kind, their location, their number and their association. This classification allows us to point out that present scales are not enough detailed and are not suitable for the reality of these injuries. On this basis we propose intermediate stages in order to refine the present AIS and MAIS scales.

Consideration for the damaging effects to aircraft from the failure of wheels and tires should be evaluated. This document discusses the types of problems in-service aircraft have experienced and methodology in place to assist the designers when evaluating threats for new aircraft design. The purpose of this document is to provide a history of in-service problems, provide a historical summary of the design improvements made to wheels and tires during the past 40 years, and to offer methodology which has been used to help designers assess the threat to ensure the functionality of systems and equipment located in and around the landing gear and in wheel wells.

Conventional trajectory planning methods encounter various challenges: Inability to better distinguish different types of vehicles, and failure to consider the difference between perceived threats or risks during asymmetric and symmetric interactions for autonomous vehicles. To solve these issues, the insufficiency of the traditional risk-field model is analyzed, and an asymmetric aggressiveness model is investigated in this study, which quantifies the suffered aggressiveness of vehicles. Then, the asymmetric aggressiveness model and the static potential risk field describing the road structure are used as the control objectives of the optimal controller to avoid collisions. Furthermore, a three-degree-of-freedom vehicle dynamics model is constructed, and the optimal feasible trajectory is planned by using the model predictive control algorithm.

Flight accidents with modern aircraft are often a result of complex dynamics of the “pilot (automaton1) - vehicle - operational environment” system. When a “critical mass” of the system’s complexity exceeds a certain level, a “chain reaction” of irreversible cause-and-effect links can be spontaneously triggered in the system behavior leading to a catastrophe. An affordable, practically tested technique is proposed to complement current methods of flight accident analysis. A generic situational model of the system behavior and a computer are employed as a virtual test article. This model includes a six-degree-of-freedom non-linear flight dynamics model, a generic situational pilot model (“silicon pilot”), models of anticipated operational factors (conditions), and a tool for flight scenario planning. Available flight recorder data are used to tune the model and reconstruct the accident.

Accident statistics indicate that postcrash fire is one of the most serious threats to human life in aircraft crashes. It is also a serious threat in automotive crashes. Several methods are available to reduce this hazard. The simplest and most effective method is through control of the fuel spillage. Aircraft crash testing has shown that fuel systems incorporating tough, flexible fuel tanks that are smooth in contour, free from rigid attachments, and mated with flexible fluid lines are capable of preventing fuel spillage during crashes involving decelerative loading above the human survival range.

The airspeed increases which appear on all flight data recorders of aircraft which crashed in microburst wind shears are examined. Two reasons for these airspeed increases are suggested which contradict previous analysis. One reason is evident now from the recent studies on optimum trajectories. Another type of airspeed increase which occurs when aircraft escape a microburst is also examined. Several cases of both types of airspeed increases are discussed to show how some previous analysis has underestimated the severity of the wind shears which consequently has caused pilots to underestimate the risks involved. With reference to the study of optimum trajectories, recommendations to pilots are examined to discover if some pilots have been taught a recovery procedure which actually decreases their chance of successful penetration of a microburst. Other suggestions to pilots are compared to those based upon the optimum trajectory analysis.

During the phase IV of the EEC biomechanical programme, the available side impact dummies were evaluated and this work concluded that none of the dummy was acceptable. The European Experimental Vehicle Committee set up a working group to built a new side impact dummy to be used in a standard side impact test. The ONSER laboratory was in charge of the development of the pelvis. This paper includes the specifications for the pelvis, agreed by the EEVC working group dealing with this subject, anthropometric analysis to choose sizes and mass distribution a description of the shape of the pelvic bone and the location and the type of transducer (force, acceleration). The design of the hip joint and the use of deformable materials to simulate the pelvic bone deformations are discussed. Results of impactor tests using a dummy fitted with this pelvis are analyzed and their results compared to those of cadavers tests conducted previously.

To attend the next generation of aircraft, which will demand higher levels of crashworthiness performance and occupant safety, the development and validation of reliable simulation tools is a very important task. Through efficient use of finite element simulation technologies, development costs and certification tests can be reduced, while meeting aircraft safety and crashworthiness requirements. The present work presents an overview of aircraft crash and occupant simulation, highlights selected topics of the finite element crash technology, review recent applications, and identify future challenges of the technology.

The CAA has previously initiated and funded research to assess the lightning threat to helicopters operating in the North Sea. One of the conclusions of this research is that lightning strikes to helicopters operating in the North Sea are more likely to involve positive polarity cloud-to-ground strikes which generally have a higher action integral than the typical negative polarity cloud-to-ground strikes. The UK-CAA is also familiar with a lightning accident to a glider North of London in 1999. One of the conclusions of the investigation into this accident was that the glider had been struck by a lightning strike with a considerably greater action integral than the present certification test threat level. EUROCAE WG31 and SAE Committee AE2 have reviewed the above data and other incident/accident reports. The available data on the severe threat is considered limited, the committees therefore requested that further evidence be presented.

Stall/spin airplane accidents result in a significant number of fatalities each year within the general-aviation community. The most effective method of reducing this type of accident is to prevent airplane stalls. The device described in this report has been shown to be effective in preventing stall of a Piper PA-18, 150 airplane, and it should also be effective on other airplanes. The system incorporates a small spoiler mounted on the under surface of the stabilizer near the elevator hinge line. The spoiler is deployed automatically by means of a servo system that receives its commands from an angle of attack sensor mounting in the wing leading edge. Thus, the operation of the system is independent of pilot reactions. The spoiler deploys to limit tail power near the wing stall angle of attack, thereby preventing the wing from reaching the angle of attack required for stalling.

This paper provides an overview of recent developments in the area of arc fault detection (AFD) and wire fault location for aircraft wiring systems. Arc faults have been identified as one of the greatest threats to human lives and properties, and the likely cause of several aircraft disasters. With the introduction of high voltage transmission in aircraft to reduce the wiring weight and to meet the increasing power demands, the probability of initiating and sustaining continuous arcs in modern aircraft have been increased. However, arc faults are hard to detect and wiring problems are difficult to locate in aircraft, due to their complex profiles, high impedance property, and pressure sensitive characteristic, etc. The difficulty in resolving this problem is also due to the fact that false alarms cannot be tolerated but missing alarms can be fatal, and arc faults are normally intermittent as a result of the in-flight vibration.

Purpose: The A4A/SAE Nondestructive Testing (NDT) Innovation Award, formerly known as the Better Way Award, is an annual process established to recognize a government and/or industry team that has developed and applied a technology, technique, process, or policy that advances inspection or test of civil/commercial aircraft structure, aircraft components, or aircraft systems. Improvements will be assessed as a function of process sensitivity, reliability, and cost effectiveness. Criteria: Team eligibility includes both government and private industry personnel. Employees of universities, national labs, and non-profit organizations are also eligible as supplemental recipients of this award. Membership in A4A or SAE is not required. Teams may have two to twelve members. The accomplishment may involve research, development, engineering, application, management, or policy, and should have occurred not more than 18 months prior to the NDT Forum.

The Automated Coatings Removal System (ACRES) is a custom robotic system developed by Southwest Research Institute® (SwRI®) to automatically remove paint from large aircraft components in a manner that is safe, efficient, and cost effective. The traditional aircraft depainting process uses manual blasting or chemical stripping methods and can have significant drawbacks: high labor usage, low repeatability, and risk of composite-surface damage. The U.S. Air Force is working proactively to implement new depainting processes that are more cost-effective, reduce the hazardous waste stream, and prevent occupational injuries. ACRES will enable the Air Force to depaint off-airframe components more efficiently and effectively. The system will provide better process consistency, reduce manpower and cost, and remove the operator from a potentially unsafe work environment.

Simulation supports aircraft safety From analyzing crashes to hard landings, the industry is evolving in how much it relies on CAE simulation to provide safer aircraft designs. As aircraft systems become more complex, simulation itself is evolving as well.

This document describes the technical requirements, architectural options, and recommended interface standards to support an Autonomous Distress Tracking (ADT) System intended to meet global regulatory requirements for locating aircraft in distress situations and after an accident. This document is prepared in response to International Civil Aviation Organization (ICAO) and individual Civil Aviation Authorities (CAAs) initiatives.

If an airplane crashes, the recorded radar data can be used to reconstruct a time history of the airplane’s calibrated airspeed, load factor, excess thrust, bank angle, etc. Previous work on this problem has used a rectilinear approach to the calculations involved in the flight parameter reconstruction. The rectilinear approach gives excellent results for relatively straight flight; however, it routinely underestimates the airspeed and the bank angle when the airplane is maneuvering. In the present study, the authors present a curvilinear approach to flight parameter reconstruction that addresses this shortcoming. The analysis presented shows that the curvilinear approach is a far superior tool than the rectilinear approach for the reconstruction of maneuvering flight including steep turns and high-speed spirals.

Human missions to Mars will represent not only a departure from the relative protection and proximity of low Earth orbit but also the way space missions are currently conducted. Traveling at 180,000 miles per second, radiofrequency communication will require up to 20 minutes to reach Mars from Earth. Extended periods of communication blackout may leave the Mars-nauts without Earth contact for weeks. Crews will be on their own to recover from mission complications, including serious crew member illness or injury. These conditions dictate unique applications of telemedicine.