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1968-02-01
Technical Paper
680789
R. Van Laethem
The new high-safety glazing is superior to that currently in use. The total thickness is reduced by half, which results in greater lightness, flexibility, and reduction of the effects of inertia. It offers very high resistance to rupture and penetration caused by external impacts by small projectiles and even repeated impacts. In the event of breakage by these exterior impacts, total visibility is maintained. In the event of internal shocks of light or moderate energy, the high resistance to rupture combined with light inertia and great flexibility means that the human tolerance limit is never reached. When these internal shocks are of high energy, progressive deceleration and considerably heightened resistance to penetration is evident, compared to the high-impact sheeting of ordinary thick glass as prescribed by USAS Z26.1. The danger of cuts is practically eliminated and the guillotine effect is totally eliminated.
1968-02-01
Technical Paper
680788
F. Brückner, H. Krings
Abstract The exchange of energy between bodies involved in an impact depends upon the elastic properties of the bodies and, owing to the sequence of the dynamic reaction during the impact, upon the shape of the impact bodies. In the case of ball and plate, the conditions in this respect are extreme ones. With regard to the forces of reaction caused by the impact of a passenger against the fastened windshield, the different reactions of the various types of safety glass have to be taken into account. In particular, the forces of reaction and the reaction times occurring must remain within human tolerance limits. New windshield systems are presented which take into account the human tolerance values of the cervical spine.
1968-02-01
Technical Paper
680791
L M. Patrick, D. J. Van Kirk, G. W. Nyquist
A versatile acceleration facility is described which accelerates and decelerates a sled or a modified automobile on its own wheels. The same propulsion and snubber systems are used for both the sled and the vehicle configurations with less than an hour required between runs. Accelerations and decelerations up to 60 g, velocities up to 60 mph, onsets of 200-2000 g/sec, acceleration distances up to 10 ft and deceleration distances up to 6 ft are available with excellent reproducibility. Extensive safety features for the operating personnel are provided.
1968-02-01
Technical Paper
680790
Bertil Aldman, Arne Ȧsberg
Abstract The response of a restrained car occupant to deceleration patterns recorded at barrier impacts with European compact cars is studied by using a simple model in an analog computer. In order to illustrate the general influence of restraint characteristics and slack, the occupant is defined as one solid mass and restraints are characterized by linear load-elongation functions of different stiffness. Various degrees of slack are introduced by delaying the response until a predetermined displacement has occurred between occupant and vehicle. Peak accelerations and total displacements of the occupant as a function of slack are given. The substitution of actual deceleration-time patterns from barrier impacts by simpler functions of similar shape shows that average deceleration rather than single peaks of short duration in the input function govern the response of the restrained occupant.
1968-02-01
Technical Paper
680776
Robert A. Rogers, Jeffrey N. Silver
Abstract This paper is a discussion of some of the more important considerations and parameters involved in child restraint system design. The success of an effective system for preventing child injury must be measured in terms of child contentment and user convenience as well as impact performance and anatomical considerations. It is the objective of this paper to stimulate the designer of child restraint systems into a realistic reappraisal of the relative importance of the four fundamental ingredients of a successful child restraint system: impact performance, child contentment, convenience, and market appeal.
1968-02-01
Technical Paper
680777
Claude Tarriere
Abstract Experimental crash data are examined to determine how vehicle rigidity influences seat belt operation. Total occupant braking distance is maximized when a vehicle has high frontal deformation, as belt loading occurs at impact. However, for any given vehicle optimum conditions occur when: 1. Dead time between impact and belt loading is minimized. 2. Seat belt webbing characteristics are matched to vehicle structure to use maximum available braking distance.
1968-02-01
Technical Paper
680778
R. W. Sonntag, W. A. Newsom, S. D. Leverett, V. E. Kirtland
Abstract Two large anesthetized chimpanzees were exposed to −150 Gx (“eyeballs out”). Both were restrained by contour supports of synthetic foam material. Both survived the experience with minor injuries, demonstrating the increased tolerance to impact provided by whole body restraint systems.
1968-02-01
Technical Paper
680779
G. Murray Mackay
Car collisions from a representative; sample of.urban and rural accidents in Great Britain have been analyzed. sA damage severity index scale has been developed which involves comparing the damage to a case vehicle with damage to a similar make and model vehicle which has been in an experimental impact. Damage severity is then correlated with injury severity for four crash configurations: head on, front corner, side, and rear end. The benefits from lap/diagonal seat belts show an increase in at least 12 mph in equivalent barrier speeds for the same injury level in head-on and front-corner impacts, but in side impacts there is no significant benefit to the occupants remaining in the cars. Penetration of the passenger compartment in side impacts and rollover is shown to be closely related to injury severity. When better experimental data are available, this method should allow different makes and models of cars to be assessed in terms of injury prevention.
1968-02-01
Technical Paper
680780
J. E. Thompson
Abstract The objective of designing vehicle structure to minimize restrained occupant responses to multicar collisions requires a detailed study of all elements of the vehicle-occupant system. Two mathematical models, an 8 deg of freedom three-dimensional occupant and a 1500 deg of freedom vehicle structure, have been developed to allow such a detailed investigation. How these two models may be combined into a total system is described, along with initial validation efforts. The validations of the occupant model and the vehicle structure model will be supported by static load tests and two-car vehicle crash data for the particular case of side impact. Validation of the models merely establishes the feasibility of the approach, which is the principal conclusion to be derived from the analytical development to this point.
1968-02-01
Technical Paper
680781
D. J. Van Kirk, W. A. Lange
A program for investigating frontal force accidents has been underway for approximately 2 years at Wayne State University. It differs from most investigations in that each accident was analyzed in detail. Accidents in which the cause of injury could not be accurately ascertained were eliminated. Thus, a limited number of cases were investigated in detail rather than depending on statistics from a large number of accidents. It was necessary to establish a comprehensive scale for the detailed investigations because available rating scales did not provide fine enough injury increments. A degree of injury scale has been devised which can be modified as new data on injury are acquired. The scale ranges from very minor injuries to fatalities with the following six major categories of injury in increasing order of severity: minor, moderate, moderate-severe, severe,critical, fatal. Each category has several subdivisions with a detailed description of each.
1968-02-01
Technical Paper
680782
L. M. Thomas, Y. Sezgin, V. R. Hodgson, L. K. Cheng, E. S. Gurdjian
Abstract Three human male cadaver heads were statically loaded along anteroposterior, posterioanterior, side to side, and vertex to base lines of action, while simultaneously measuring skull deflections at four or five locations and intracranial volume changes. Volume changes due to loading along the long (A-P) axis were small and either increased or decreased, while loads transverse to the A-P axis decreased the volume. Transverse loads produced volume changes on the order of 10 times larger than those due to A-P forces. Two skulls loaded to fracture in the A-P direction, failed at 1150 and 2200 lb, respectively, into the right orbit. These magnitudes and linear fracture direction correspond to four fractures produced by impact to the frontal bone of intact cadavers in previous work.
1968-02-01
Technical Paper
680771
Arnold W. Siegel, Alan M. Nahum, Michael R. Appleby
Forty-six automobile collisions with 82 child occupants have been studied. Emphasis was placed on the mechanism of injury production and child collision kinematics. A number of case examples illustrate these injury patterns. Also included are example cases of the effects of collisions in pregnancy and cases of restrained children. Childhood growth characteristics as they affect injury patterns and restraint systems are discussed in detail. An analysis of current types of restraint systems is included and recommendations are made. Collision and comfort-convenience requirements of an “ideal” restraint system are listed.
1968-02-01
Technical Paper
680773
John D. States, David J. States
Abstract Forty-eight lateral impact accidents were studied correlating vehicle damage and occupant injury. Side-swipe accidents produced serious injury only when the occupant's elbow was protruding through a window or when the occupant space of the vehicle was seriously compromised. Intersection impacts and drifting impacts, particularly when the impact was caused by a vehicle approaching from the opposite direction, caused the most serious injuries. Fractures of the acetabulum with intrapelvic protrusion of the hip and fractures of the pubic rami are characteristic of lateral impact accidents. The door was the most common injury-producing structure of the vehicle. Deep wrap-around seat designs and stronger doors, door frames, and chassis structures are necessary to reduce occupant space penetration and to absorb impact energy in lateral impact accidents.
1968-02-01
Technical Paper
680775
John L. Martinez
Abstract A nonlinear mathematical model is used to predict head motions during an automotive rear-end collision. The physical characteristics of the seat back are extremely important factors in the mechanics of the torso and head of the car occupant. This paper studies the velocity and displacement as well as acceleration patterns of the subject's head and torso on absolute and relative bases. Once these patterns are established, mathematical experiments are performed to study the variation in patterns produced. Specifically, the concept of the yielding seat back (damped and undamped) is studied as a design concept for attenuating the impact experienced by the subject in the rear-end collision.
1968-02-01
Technical Paper
680666
Joan B. Barriage, D. Michael Brandewie
The STOL and VTOL air transportation system depends on the timely coordinated development of the aircraft, the navigation, and the air traffic control facilities and the ground space facilities. This paper discusses the aircraft characteristics as a background to the manner in which STOL and VTOL aircraft will be operated in both intra- and intercity operation and considers the impact on the navigation and air traffic control.
1968-02-01
Standard
ARP465
This SAE Aerospace Recommended Practice (ARP) provides guidance for the design of flanges on temperature sensors intended for use in gas turbine engines. Three figures detail the configuration of standard size flange mounts with bolt holes, slotted flanges, and miniaturized flanges for small probes.
1968-02-01
Technical Paper
680774
Derwyn M. Severy, Harrison M. Brink, Jack D. Baird
Scientific methodology and engineering techniques were applied to a series of three automobile rear-end collision experiments to provide data relating to seat, seat backrest, and head-restraint design. Five seat back heights and four seat back strength values were studied in connection with their practicality and relative protective features, when subjected to a 55 mph rear-end collision exposure. These research data provide a basic reference system of high-speed collision performance for seat designs with respect to occupant size and proximity to injury producing structures. Additionally, methodology, instrumentation, and related equipment required for post-crash fire studies were included in experiment 106, providing what is believed to be the first published data on the precise time-related events associated with collision-induced passenger car fires. Design revisions suggested by these findings are discussed.
1968-02-01
Magazine
1968-02-01
Technical Paper
680786
John M. Douglass, Alan M. Nahum, Sanford B. Roberts
The types and mechanisms of head injury are reviewed, and then the findings of a UCLA study on the electrophysiology of primate concussion is presented. It was found that g loadings, as measured by a triaxial accelerometer attached to the skull of an impacted monkey, correlated well with severity of concussion. Deep and superficial cerebral electrodes were implanted to monitor electroencephalographic and impedance changes after concussion. Resistance dropped and capacitance rose in the impedance electrodes in direct proportion to the severity of concussion. Deep electroencephalographic recordings showed a high amplitude low frequency charfge in the reticular formation areas after impact. Superficial electroencephalographic recordings did not correlate with clinical states. Applications of these data are presented as they relate to the prevention and treatment of head injury.
1968-02-01
Technical Paper
680785
Alan M. Nahum, James D. Gatts, Charles W. Gadd, John Danforth
Abstract Forces necessary for fracture under localized loading have been obtained experimentally for a number of regions of the head. Three of these, the frontal, temporoparietal, and zygomatic, have been studied in sufficient detail to establish that the tolerances are relatively independent of impulse duration, in contrast with the tolerance of the brain to closed-skull injury. Significantly lower average strength has been found for the female bone structure. Other regions reported upon more briefly are mandible, maxilla, and the laryngotracheal cartilages of the neck. Pressure distribution has been measured over the impact area, which has been 1 sq in. in these tests, and the relationship between applied force as measured and as predicted from a head accelerometer is examined.
1968-02-01
Technical Paper
680783
S. W. Greenberg, D. Gonzalez, E. S. Gurdjian, L. M. Thomas
Abstract A knowledge of the state of the physical properties of cadaver material is important if such material is utilized for impact studies. Experiments were designed to evaluate changes in elastic and strength properties of bone in the experimental animal in the course of its transition from live to recent death to embalmed conditions. Results indicate less than 5% change from the live to the fresh condition. In progressing to the embalmed wet condition variable degrees of stiffening are observed averaging around 8%. Drying of embalmed bone further increases stiffness about 24% and remoistening reconstitutes some of the initial flexibility.
1968-02-01
Technical Paper
680792
Channing L. Ewing, Daniel J. Thomas, George W. Beeler, Lawrence M. Patrick, David B. Gillis
Abstract An acceleration sled carrying living human subjects was used to measure the dynamic response of the head and neck to —G x impact acceleration. Seated volunteers with complete pelvic and upper torso restraint were subjected to increasing impact accelerations beginning at 2.7 g and increasing in 1 g increments. The volunteers were selected to encompass the 5th to 95th percentile distribution of sitting height according to a selected reference. Precision inertial transducers were used to determine the linear and angular acceleration of the head and the first thoracic vertebra. The inertial system consisted of a biaxial accelerometer and rate gyroscope on a bite-plate, a biaxial acceierometer over the bregma, and a biaxial acceierometer and rate gyroscope over the spinous process of the first thoracic vertebra. The transducers on the bite-plate and over the bregma were rigidly connected to one another.
1968-02-01
Technical Paper
680772
John W. Garrett
Abstract The objective of this study is to determine whether gross passenger car characteristics are associated with the frequency of vehicle rollover. The characteristics examined are vehicle weight, track width, and vehicle height. Data used in the study are drawn from two states participating in the ACIR program and represent all accidents, property damage as well as injury, investigated by the state police for a period of one year. Data from each state are examined independently and results are then compared. The data indicate that there is a strong correlation between rollover frequency and vehicle dimensions: rollover increases as car size shifts from heavy, wide track, low vehicles to light, narrow track, high cars. Car weight and tread width appear to have the greatest influence on vehicle overturn.
1968-02-01
Technical Paper
680016
Richard I. Emori
Analyses of some of available experimental results suggest that frontal and rear-end automobile collision processes may be simulated by a simple model with a mass, which represents the vehicle mass, and a spring, which represents the resisting force due to crushing of the vehicle structure. Indications are that in the case of barrier and head-on collisions, the spring is one-way linear, and the rate does not vary with colliding speeds provided that the type of vehicle and the mode of collisions remain the same. On the other hand, in the case of rear-end collisions, experiments indicate that the spring is almost rigid-plastic. The occupant's motion was also studied by a simulated model. A parametric study was made to obtain a design criterion for safety harnesses and vehicle interior geometry relative to occupants for injury reduction.
1968-01-01
Standard
AIR797A
This document lists military and industry specifications and standards which are used in aerospace systems and for ground servicing equipment. The characteristic limitations of the hose, which are of major importance to designers, and the sizes in which the hoses are standard are shown. Revisions and amendments, which are current for these specifications and standards are not listed.
1968-01-01
Magazine
1967-12-01
Magazine
1967-11-01
Standard
AS1046
This standard is intended to apply to portable compressed gaseous oxygen equipment. When properly configured, this equipment is used either for the administration of supplemental oxygen, first aid oxygen or smoke protection to one or more occupants of either private or commercial transport aircraft.
1967-11-01
Standard
ARP998
This ARP is intended to make recommendations for flight crew and cabin attendant restraint systems in aircraft. A properly designed crew restraint system will avoid injury or debilitation during a survivable crash and enable post crash assistance to occupants and escape from the aircraft. Consideration is given to existing requirements of the FAA and to the recommendations of aircraft operators and those involved in the manufacture or use of restraining devices. Crew member safety is the primary objective, with appropriate provisions for crew comfort taken into consideration. The criteria established herein are designed to standardize restraining systems without hindering the development of new, improved systems.
1967-11-01
Magazine
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