Browse Topic: Hazards and emergency operations
Radiation has garnered the most attention in the research that has been conducted on polyethylene sheets. According to the calculations, there were 145892.35 kGy in total radiation doses administered. An ultraviolet visible spectrophotometer was used to examine the impact that electron beam irradiation had on the optical constants. Two of the most crucial variables taken into account when calculating the optical constants and the absorption coefficient are the reflectance and transmittance of polyurethane sheets. Reduced light transmission through the sheet achieves these characteristics, which are related to the transmittance and reflectance of the Fresnel interface. Cross linking makes it more challenging for the polyurethane molecular chains to become fixed. Both the refractive index and the dispersion properties have been altered as a direct result of this. Despite the fact that the doses of electron irradiation were getting lower, it eventually rose to 105 kGy. Contrary to the
This ARP provides design and performance recommendations for emergency exits in the passenger cabin. This ARP does not apply to Crew Emergency Exits
This specification covers a shampoo type carpet cleaner in the form of a liquid
ABSTRACT Abuse response of lithium-ion batteries has been extensively studied over several decades. Most studies on the onset and propagation of battery fires following mechanical deformation are focused on understanding the onset of thermal events following quasi-static loading. Using an array of cylindrical lithium-ion cells as example, we report results from ultra-high strain-rate deformation mechanical events (> 100 /s) that result in electrochemical short-circuits followed by thermal events. We present a methodology that takes stock of gas compositions as a function of state of charge and compute flammability limits. Finally, we discuss implications for flame lengths and propensity for propagation of thermal events. Citation: J. Kim, A. Mallarapu, S. Santhanagopalan, Y. Ding, “Propagation of Fire in Li-Ion Batteries under Ultra-High Strain-Rate Deformation” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA, Novi, MI, Aug. 16-18, 2022
ABSTRACT Northrop Grumman has developed a software and hardware solution to provide enhanced 360 degree local situational awareness (LSA) to enable the warfighter with an overmatch capability on today’s modern battlefield. The architecture exploits technological gains in cameras, video processing, and video compression. The approach allows rapid comprehension of local and remote situational views presented with operational relevance for a ground combat platform or tactical wheeled platform crew. The 360 Degree LSA approach provides direct visualization of relative positioning of targets, threats, and lines of fire; and additionally offers common situational understanding / operational picture from the dismounted soldier to higher echelon commands. The approach provides prioritized information through LSA software to provide an enhanced view to the warfighter whereas the squad leader becomes an integral part of the crew with a view of the common operating picture (mounted) and
ABSTRACT Raytheon is in the final stages of production of three high performance thermal imaging / fire control systems being integrated on existing USMC and US Army armored vehicles. A goal in the design of these systems was to provide integration into the host vehicle that when viewed by the customer and user provided the enhanced capabilities of today’s latest thermal imaging and image processing technology as well as operating in concert with the vehicle as originally designed. This paper will summarize the technical solutions for each of these programs emphasizing the thermal imaging, fire control, image processing and vehicle integration technologies. It will also outline guiding philosophies and lessons learned used to focus the design team in achieving the successful integration. The programs to be reviewed are; USMC 2nd Gen Thermal Imaging System, the USMC LAV-25 Improved Thermal Sight System (ITSS) and the USMC / US Army M1A1 50 Cal Thermal Sight / DayTV System
In the fall of 2023, NASA hot fire tested an aluminum-based, 3D-printed rocket engine nozzle. What made the event remarkable is that aluminum isn’t typically used for additive manufacturing because the process causes it to crack, and it isn’t used in rocket engines due to its low melting point. Yet the test was a success
Letter from the Focus Issue Editors
The environment and test waveforms defined in this SAE Aerospace Recommended Practice (ARP) account for the best lightning data and analysis currently available. The quantified environment and levels herein represent the minimum currently required by certifying authorities, which is consistent with the approach applied in related lightning documents. Lightning, like other weather phenomenon, is probabilistic in nature. Levels and waveforms vary considerably from one flash to the next. Within this document, standardized voltage and current waveforms have been derived to represent the lightning environment external to an aircraft. These standardized waveforms are used to assess the effects of lightning on aircraft. The standardized external current waveforms have, in turn, been used to derive standardized transient voltage and current test waveforms that can be expected to appear on cable bundles and at equipment interfaces within an aircraft. When deriving these latter internal induced
It is well known that target state estimation and prediction methods can have a substantial influence on the outcome of long range, precision-oriented engagements. Due to this fact, a collection of techniques and algorithms have been developed for the purpose of minimizing the delivery error caused by target motion over the flight time of a munition. These legacy compensation techniques have typically come from direct fire, accuracy-oriented assets such as main battle tanks and attack helicopters. However, with the proliferation of unmanned vehicles in the battle space, the target state estimation and prediction capabilities could be extended into the indirect fire domain. The work conducted within examines the challenge of utilizing a reconnaissance drone partnered with a decoupled weapon platform to track a target, predict its motion, and calculate a lead. The information presented within establishes the framework required to enable this capability, develops the individual solution
This document provides guidance for oxygen cylinder installation on commerical aircraft based on airworthiness requirements, and methods practiced within aerospace industry. It covers considerations for oxygen systems from beginning of project phase up to production, maintenance, and servicing. The document is related to requirements of DOT-approved oxygen cylinders, as well to those designed and manufactured to standards of ISO 11119. However, its basic rules may also be applicable to new development pertaining to use of such equipment in an oxygen environment. For information regarding oxygen cylinders itself, also refer to AIR825/12
This SAE Aerospace Recommended Practice (ARP) recommends design features for facilitating relocation of portable slide/rafts for deployment at an alternate exit under ditching conditions
Because they can go where humans can’t, robots are especially suited for safely working with hazardous nuclear waste. Now, scientists at the U.S. Department of Energy’s (DOE) Argonne National Laboratory have designed and tested a remote-controlled, dual-arm telerobotics system with human-like capabilities that has the potential to revolutionize hazardous waste clean-up and holds potential for broader applications
Researchers at the National Institute of Standards and Technology (NIST) and colleagues have developed standards and calibrations for optical microscopes that allow quantum dots to be aligned with the center of a photonic component to within an error of 10 to 20 nanometers (about one-thousandth the thickness of a sheet of paper). Such alignment is critical for chip-scale devices that employ the radiation emitted by quantum dots to store and transmit quantum information
Researchers at Tufts School of Engineering have developed a method to detect bacteria, toxins, and dangerous chemicals in the environment with a biopolymer sensor that can be printed like ink on a wide range of materials — including wearables
Advances in optical sensors and imaging technologies are ever more rapidly assimilated into how humans interact, understand themselves, and explore the world around them. The scope of inquiry for optical devices is broad and they enable technologies within, such as implanted transdermal bioMEMS devices, and beyond, or as space-flight surveyors deployed as near and deep space instruments. Central to the functionality of modern optical devices, ultra-narrow bandpass (UNBP) thin-film optical filters enable discrimination of sub-nanometer bands inside broad spectra. These filters, pioneered as NIR DWDM filters for the telecommunications industry, are now essential in extracting meaningful signal from imaging and sensing devices operating anywhere between the deep ultraviolet and the mid infra-red bands
Sensor packaging, particularly for microelectromechanical systems (MEMS), is a critical aspect of modern electronics. MEMS developers have demonstrated a variety of innovative microsensors for almost every possible sensing modality including temperature, pressure, inertial forces, chemical species, magnetic fields, radiation, etc. While MEMS sensors are revolutionizing various industries with their precision and miniaturization, they can present unique product development challenges and risks during design, development, and manufacturing
Notice of Withdrawal
This SAE Aerospace Information Report (AIR) describes the aspects of hydraulic system design and installation to minimize the effects of lightning. Techniques for effective electrical bonding, hydraulic system lightning protection, and lightning protection verification techniques are discussed
In any human space flight program, safety of the crew is of utmost priority. In case of exigency in atmospheric flight, the crew is safely and quickly rescued from the launch vehicle using Crew Escape System (CES). CES is a critical part of the Human Space Flight which carries the crew module away from the ascending launch vehicle by firing its rocket motors (Pitch Motor (PM), Low altitude Escape Motor (LEM) and High altitude Escape Motor (HEM)). The structural loads experienced by the CES during the mission abort are severe as the propulsive, aerodynamic and inertial forces on the vehicle are significantly high. Since the mission abort can occur at anytime during the ascent phase of the launch vehicle, trajectory profiles are generated for abort at every one second interval of ascent flight period considering several combinations of dispersions on various propulsive parameters of abort motors and aero parameters. Depending on the time of abort, the ignition delay of PM, LEM and HEM
A global team of researchers and industry collaborators led by RMIT University has invented recyclable ’water batteries’ that won’t catch fire or explode
Remember that party where you were swinging glow sticks above your head or wearing them as necklaces? Fun times, right? Science times, too. Turns out those fun party favors are now being used by a University of Houston researcher to identify emerging biothreats for the United States Navy
Northwestern University researchers have developed new devices based on a low-cost material to aid in the detection and identification of radioactive isotopes. Using cesium lead bromide in the form of perovskite crystals, the research team found that they were able to create highly efficient detectors in both small, portable devices for field researchers and in very large detectors. The results are more than a decade in the making
Where there’s smoke, there will be no fire because a drone is already on the scene. At least that’s the hope of Zhaodan Kong, Professor in the Department of Mechanical and Aerospace Engineering, and his team at the University of California, Davis
Focused on the permanent magnet synchronous motor (PMSM) used in electric, this paper proposes an online insulation testing method based on voltage injection under high-temperature and high-humidity conditions. The effect of constant humidity and temperature on the insulation performance has been also studied. Firstly, the high-voltage insulation structure and principle of PMSM are analyzed, while an electrical insulation testing method considered constant humidity and temperature is proposed. Finally, a temperature and humidity experimental cycling test is carried out on a certain prototype PMSM, taking heat conduction and radiation models, water vapor, and partial discharge into account. The results show that the electrical insulation performance of the motor under constant humidity and temperature operation environment exhibits a decreasing trend. This study can provide theoretical and practical references for the reliable durability design of PMSM
Northrop Grumman Corporation is developing AN/APG-85, an advanced Active Electronically Scanned Array (AESA) radar for the F-35 Lightning II. Northrop Grumman currently manufactures the AN/APG-81 active electronically scanned array (AESA) fire control radar, the cornerstone to the F-35 Lightning II’s sensor suite
Items per page:
50
1 – 50 of 5799