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The article presents a mathematical model of ejection process, which can be used to analyse the movement of the seat-pilot system in flight phase until ejecting the headrest and may also be utilised to assess the movement of the seat after the pilot has separated when the seat has been propelled out of the aircraft. By constructing the model, the information was used regarding the K-36DM ejection seat, which was supplemented with data on other ejection seats. The demonstrated mathematical model provides a basis to produce a simulation model useful in estimating the efficiency of ejection applying the K-36DM seat. [ABSTRACT FROM AUTHOR]

The paper deals with the conceptual design and sizing of a cabin escape system to be applied to a trans-atmospheric transportation system. At first, the role of suborbital vehicles towards the development of a hypersonic transportation system is presented. From this analysis, it has been clear that one of the key points in enhancing the public consensus is to demonstrate a higher level of safety and reliability with respect to the current space vehicles. Since the time of the Space Shuttle enterprise, the development of a proper escape system has been considered crucial to diminish the risk of loss of lives per mission, moving from space-like reliability characteristics to values closer to the aeronautical case. In particular, this paper presents the conceptual design of an escape system for a single stage vehicle aimed at parabolic flights. The proposed design methodology starts with the identification of the major requirements that will lead the design and sizing activities. Then, special attention is devoted to the identification of the required capabilities of a Cabin Escape System and to the selection of the proper subsystems able to guarantee these functionalities. Indeed, considering the high-level of complexity of such a system, during the design process, specific attention should be paid to the impact of on-board systems integration on the overall transportation system architecture and layout. At this purpose, a proper utilization of CAD models can ease the integration process allowing fast verification of mass and volume budgets as well as integrated simulation techniques could be useful. Furthermore, the possibility of exploiting this system during the different phases of the mission should be properly evaluated and, eventually, a preliminary impact risk analysis is reported. [ABSTRACT FROM AUTHOR]

The testing of aircraft ejection seats has been an important aspect of testing in the aerospace industry for several decades. Identification and tracking of aircraft ejection seat systems, during field testing, has practical benefits in post-test analysis and real-time tracking applications. This paper proposes a methodology to identify and locate ejection seat systems in a video stream as they are propelled from a dynamic aircraft test bed. The field testing environment is cluttered with natural and man-made artifacts that effect the background appearance and make the video stream data visually noisy. The identification problem involves the extraction of critical information from the video stream and feeding it into a deep learning convolutional neural network that determines the location of the ejection system within the field of view. The results achieved, using the convolutional neural network to identify features of the ejection seat system, were promising. In particular, the convolutional neural network demonstrated an ability to identify objects that were in a different spatial orientation (rotation) than were used to train the network. [ABSTRACT FROM AUTHOR]

The bombing delivery systems can improve survivability and delivery accuracy. Despite conventional, wings-level dive bomb delivery can achieve acceptable accuracy an aircraft is vulnerable during maneuvering to weapon release. [ABSTRACT FROM AUTHOR]

Background: Improvised explosive devices are a common feature of recent asymmetric conflicts and there is a persistent landmine threat to military and humanitarian personnel. Assessment of injury risk to the spine in vehicles subjected to explosions was conducted using a standardized model, the Dynamic Response Index (DRI). However, the DRI was intended for evaluating aircraft ejection seats and has not been validated in blast conditions. Questions/purposes: We asked whether the injury patterns seen in blast are similar to those in aircraft ejection and therefore whether a single injury prediction model can be used for both situations. Methods: UK military victims of mounted blast (seated in a vehicle) were identified from the Joint Theatre Trauma Registry. Each had their initial CT scans reviewed to identify spinal fractures. A literature search identified a comparison population of ejected aircrew with spinal fractures. Seventy-eight blast victims were identified with 294 fractures. One hundred eighty-nine patients who had sustained aircraft ejection were identified with 258 fractures. The Kruskal-Wallis test was used to compare the population injury distributions and Fisher's exact test was used to assess differences at each spinal level. Results: The distribution of injuries between blast and ejection was not similar. In the cervical spine, the relative risk of injury was 11.5 times higher in blast; in the lumbar spine the relative risk was 2.9 times higher in blast. In the thoracic spine, the relative risk was identical in blast and ejection. At most individual vertebral levels including the upper thoracic spine, there was a higher risk of injury in the blast population, but the opposite was true between T7 and T12, where the risk was higher in aircraft ejection. Conclusions: The patterns of injury in blast and aircraft are different, suggesting that the two are mechanistically dissimilar. At most vertebral levels there is a higher relative risk of fracture in the blast population, but at the apex of the thoracic spine and in the lower thoracic spine, there is a higher risk in ejection victims. The differences in relative risk at different levels, and the resulting overall different injury patterns, suggest that a single model cannot be used to predict the risk of injury in ejection and blast. Clinical Relevance: A new model needs to be developed to aid in the design of mine-protected vehicles for future conflicts. [ABSTRACT FROM AUTHOR]

INTRODUCTION: The purpose of this investigation was to identify factors associated with Air Force aviators delaying ejection during in-flight emergencies. METHODS: The investigator reviewed all reports within the Air Force Safety Automated System describing mishaps that resulted in the destruction of Air Force ejection-seat equipped aircraft between 1993 and 2013. Crewmembers were classified as either timely or delayed ejectors based on altitude at onset of emergency, altitude at ejection, and a determination regarding whether or not the aircraft was controlled during the mishap sequence. Univariate analysis and multivariate logistic regression were used to explore the association between delayed ejection and multiple potential risk factors. RESULTS: In total, 366 crewmembers were involved in in-flight emergencies in ejection-seat-equipped aircraft that resulted in the loss of the aircraft; 201 (54.9%) of these crewmembers delayed ejection until their aircraft had descended below recommended minimum ejection altitudes. Multivariate analysis indicated that independent risk factors for delayed ejection included increased crewmember flight hours and a mechanical or human-factors related cause of the emergency versus bird strike or midair collision. DISCUSSION: This investigation provided quantitative assessments of factors associated with aviators delaying ejection during in-flight emergencies. Increased odds of delay among crewmembers with greater than 1500 total flight hours suggests that complacency and overconfidence may adversely influence the ejection decision to at least as great a degree as inexperience, increased odds of delay during mechanical and human factors mishaps confirms previously reported hypotheses and reaffirms the importance of targeting these areas to reduce aviator injuries and fatalities. [ABSTRACT FROM AUTHOR]

The current paper presents a statistical analysis of a recent research made by the author [1], showing the factors causing the accidents that happened in Romanian Air Force from 1952 to 2014. Also the decision of ejection is analyzed. The study contains 225 events: 110 catastrophes and 115 accidents. 280 fighter pilots and 235 aircraft were involved in this analysis. The below information is a personal one and does not reflect an official position of the Ministry of National Defence. [ABSTRACT FROM AUTHOR]

SUMMARY The aim of this study is to investigate the dynamic response of a multi-segment model of the thoracolumbar spine and determine how the sitting posture affects the response under the impact of ejection. A nonlinear finite element model of the thoracolumbar-pelvis complex (T9-S1) was developed and validated. A multi-body dynamic model of a pilot was also constructed so an ejection seat restraint system could be incorporated into the finite element model. The distribution of trunk mass on each vertebra was also considered in the model. Dynamics analysis showed that ejection impact induced obvious axial compression and anterior flexion of the spine, which may contribute to spinal injuries. Compared with a normal posture, the relaxed posture led to an increase in stress on the cortical wall, endplate, and intradiscal pressure of 43%, 10%, 13%, respectively, and accordingly increased the risk of inducing spinal injuries. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article offers information on the Helicopter Underwater Escape Training (HUET) which simulates escaping of offshore helicopter passengers using a single seat that was manually operated, a wooden box, and two tripod supports.

The performance of a two-stage ejector during high-altitude testing of large-area-ratio satellite thrusters is numerically investigated. Since the flow rate of the exhaust from the satellite thruster is very low, self-ejector action of the exhaust is quite weak; therefore, a two-stage external ejector is required to create the desired low vacuum in the test chamber. The present work attempts to investigate the effects of various operational and geometric parameters on the performance of the two-stage ejector. Predicted results show that the downstream ejector (E2) operation is more critical for maintaining the required vacuum. However, for optimal performance, it is possible to tune the parameters such that both ejectors deliver the same suction effect. Maximum performance of each ejector is obtained when the primary jet expanding from the nozzle smoothly seals the mixer throat against backflow. Employing a low molecular weight fluid and high stagnation temperature helps in reducing the quantity of fluid required for test facility evacuation. Useful correlations have been derived to quantify the suction performance of the two-stage ejector, and the predicted results compare well with in-house experimental data. [ABSTRACT FROM AUTHOR]

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Abstract: An experimental technique is established to induce a prescribed upward acceleration-time load on the human head–neck complex. The primary objective is to replicate experimentally the initial loading history experienced at the base of the cervical spine during pilot ejection from a cockpit. A drop tower is specially modified to achieve this and seven head–neck complexes from male human cadavers were tested. The experimental acceleration-time results follow the desired profiles closely. High-speed photography is used to capture visual images of the ejection process to examine the dynamic response of specimens and to derive kinematic data on vertebrae motion during ejection. [Copyright &y& Elsevier]

The article presents a study concerning back propagation neural network through predicting ejection velocity of ejection seat. It notes that the primary parameter of the sequencer control subsystem is the ejection velocity of the escape system which has determined the parachute shooting time. It mentions that the study has found out that an error of the measured velocity is created.

In this article, we apply the well-known equations of projectile motion to the case of a fighter pilot ejecting from an aircraft, the aim being to establish under what conditions there is danger of impact with the rear vertical stabilizer. The drag force on the pilot after ejection is assumed to vary as the velocity squared and the aircraft motion is assumed to be confined to a plane (i.e. roll, yaw and pitch are not included), but it is not restricted to horizontal flight. The study is, however, limited to the case of no propulsion force acting on the pilot after ejection, as is appropriate to the older style of ejection seat. The problem has been coded in Matlab and some illustrative numerical results are presented. We envisage that student interest in the numerical solution of differential equations will be stimulated by this application of projectile motion to an interesting real-life and potentially life-threatening situation. [ABSTRACT FROM AUTHOR]

Aerodynamic characteristics of an Ejection Seat System at different angles of attack are studied by the numerical method and the flow mechanisms for such flows are carefully analyzed. The governing equations are Reynolds-averaged Navier-Stokes equations which are solved by the unstructured finite volume method. Upwind Osher scheme is used for spatial discretization and five-stage Runge-Kutta scheme is applied for temporal discretization. The DES model based on S-A one equation turbulence model is adopted. Parallel computation is based on the domain decomposition method and multi-block is achieved by using METIS system. The experimental data is used to validate this method. This research is helpful to understand the aerodynamic characteristics and flow mechanisms of Ejection Seat System at different angles of attack and Mach numbers, and can provide reasonable reference for Ejection Seat System design. [ABSTRACT FROM AUTHOR]

The current paper presents a novel method for the production of body-fitting customized seat profiles utilizing the following digital methods: three-dimensional laser scanning, reverse engineering and rapid manufacturing (RM). Seat profiles were manufactured in order to influence the comfort characteristics of an existing ejector seat manufactured by Martin Baker Aircraft Ltd. The seat, known as the Navy Aircrew Common Ejection Seat (NACES), was originally designed with a generic profile. This paper shows the replacement of this profile with shapes captured from fast jet pilots. Pressure mapping of occupied seats, has shown that the pressure distribution under the buttocks can be influenced using body-fitting design and thus comfort is directly affected. The paper discusses the relevance of RM with respect to mass customization and personalization and, in addition, recognizes RM as a next generation manufacturing system (NGMS) capable of satisfying increasingly diverse products and lower volume production. A generic customization process is reviewed to identify areas of technical difficulty and key issues in the cost-effective customization of products. [ABSTRACT FROM AUTHOR]

The article discusses a study which analyzed ejection seat test techniques that can be used in a high-speed wind tunnel. Information on the general technical scheme and patented model support system used in the study is provided. Schematic diagrams showing the ejection seat model are presented. The reliability analysis of the test results is also discussed.

Surviving ejection from a military aircraft is a stressful experience. A restrospective of 175 Royal Air Force ejectees showed that 40 per cent had significant adverse emotional reaction and that the rate of return to operational flying was significantly reduced in this group. Composite vignettes of a satisfactory and a poor outcome are presented, and the role of the psychotherapist in alleviating the commonly encountered emotional reactions is described. Confidential counseling is most helpful. Attention must be paid to the nature, personal meaning and social context of the ejection experience. [ABSTRACT FROM AUTHOR]