Browse Topic: Lightning

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Standardized composite training programAIR6671 (Current)11/26/2025
SAE CACRC has produced several standards, each representing the best-practice, recommended minimum training syllabus for the aforementioned target groups. The purpose of this document is to promote the use of these SAE standards, particularly for developing training programs for employee training, qualification in airlines and maintenance organizations, and as reference in regulatory guidance material. It summarizes, as a quick reference, the content of each training document and its relation to and interaction with other training documents. Thereby it allows users to select the appropriate training documents and syllabi to establish a comprehensive, sequential training program build-up customized to the specific needs of the aforementioned functions (see figure). This document does not intend to introduce new training content/syllabus.
AMS CACRC Commercial Aircraft Composite Repair Committee
Aerospace - Lightning Effects on Hydraulic Transport Elements on AircraftAIR6185A (Current)11/26/2025
<p>This SAE Aerospace Information Report (AIR) describes hydraulic system design and installation to minimize the effects of lightning, especially when the aircraft structure is composite. Techniques for effective electrical bonding, hydraulic system lightning protection, and lightning protection verification techniques are discussed.</p>
My new committee for commercial aircrafts
Lightning Strike Experiments and Their Direct Effects on Flax Fiber-Reinforced Polymer Panels for Rotorcraft ComponentsF-0080-2024-13075/7/2024
This paper experimentally investigates direct effects of lightning strikes on flax fiber-reinforced polymers. Highcurrent artificial lightning strikes are conducted on coupon level to evaluate thermo-mechanical damage and to quantify the sufficiency of copper wire mesh as lightning strike protection (LSP). The dataset shall also serve for verification of prospected numerical simulation. The natural fiber flax, as a sustainable source of composite reinforcement, has been demonstrated to be suitable for semi-structural parts of rotorcraft. However, its low electrical and thermal conductivity requires a functional LSP layer for aviation applications. The test panels are investigated regarding their material combination, stacking sequence and level of LSP. Results show that two as well as three layers of 72 g/m2 copper mesh are not sufficient to withstand the standardized lightning current component A waveform of 200 kA. The high induced currents and low capability of energy dissipation
Gaugelhofer, Lukas, Yavrucuk, Ilkay, Hajek, Manfred, John, Jonas
Lightning eMotors adapts to changing electrification market22TOFHP08_058/1/2022
A growing number of commercial truck fleets are moving to electric vehicles, driven partially by government mandates and support funding. For suppliers like Lightning eMotors, that means adapting to changing markets and creating designs for both a range of new vehicles and techniques that efficiently convert aging internal-combustion engine (ICE) vehicles to electrified powertrains. Lightning is currently expanding its efforts in repowering ICE trucks and buses with electric systems, but it's also inked new vehicle partnerships with General Motors and school bus supplier Blue Bird Corp. Founded in 2008, Lightning began with a focus on hybrid vehicles but switched to fully electric designs in 2016.
Costlow, Terry
Design and Computational Investigations of Aerobot for Titan with maneuverability using momentum wheel and propeller equipped with droppable weather stations 2022-26-11915/26/2022
Titan, Saturn’s largest moon and the only celestial body which is found to have a landmass composed of liquid hydrocarbons. Nitrogen – The building block of all life that exists on earth is found to be abundant in Titan’s atmosphere of up to 97%. Aerobots provide a great platform for exploring a celestial body with an atmosphere such as Titan. They have modest power requirements, longer mission duration, and can cover a longer distance in a shorter time. They are powered by Radioisotope Thermoelectric Generator for optimal mission life. Aerobot’s altitude can be altered by varying the temperature of the air inside the balloon and yaw can be controlled using Reaction Wheel and a motor-driven propeller for forwarding thrust. The proposed Aerobot will be equipped with four miniature deployable fixed weather stations that can be dropped from the aerobot to titan’s surface. They can be deployed at diverse locations such as the equator and Polar Regions to deeply explore the Titan’s climate
Raja, Manoj Kumar, Sivasankaran, Abinash Nataraj, Saravana Mohan, Haribalan, Thangavel, Sabari, R, Vijayanandh, Gnanasekaran, Raj Kumar
Method for Performing Indirect Lightning Test Simulation2022-26-11825/26/2022
From the statistics it has been observed that major qualification test failures in aerospace system are from lightning tests. These failures lead to major cost and schedule implications as fixing these issues later in the design usually requires a product re-spin. To avoid such failures, testing of critical interfaces using simulation allows engineers to investigate the behavior of the product/system in different scenarios and visualize the effect of these changes at an earlier stage in the design. Achieving this through simulation also eliminates the need of heavy costs associated with physical prototyping & testing. The existing simulation techniques use prebuilt & formula-based lightning waveform models and also do not take into consideration the end to end impedance characteristics like cable impedance, remote impedance, etc. With these available techniques, achieving results closer to practical scenarios is difficult. To overcome some of these challenges, this paper presents a
Rajeurs, Ajaypal, Gouda, Vidyadhar
ASSEMBLED COUPLING ENVELOPE, THREADLESS - FLEXIBLE, FIXED CAVITY, CURRENT CARRYING, SELF BONDING, ENVELOPE DIMENSIONSAS7511B (Current)12/22/2020
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
Status and Way Forward on Rotorcraft Lightning ProtectionF-0076-2020-1634510/5/2020
This paper provides an overview of the state of art on the lightning regulation and the means of compliance for lightning certification, based on both the simulation technics and the testing methods. Usual lightning protection solutions at helicopter level to fulfill lightning requirements are discussed, as well as advanced approaches used by Airbus Helicopters to minimize the weight penalty of the lightning protection, especially by a large use of the simulation for the optimization of both the indirect effects (LIE) and the lightning direct effects (LDE). Some perspectives are highlighted concerning the development of new lightning protection devices to withstand the higher induced currents coupled on equipment items installed in full composite airframe helicopters (H/C), and how the lightning may be avoided on future platforms like the emergent flying urban taxis.
Zehar, Sonia, Meyer, Marc, Tagliana, Bernard
Remotely Piloted Air SystemsTBMG-3788210/1/2020
General Atomics Aeronautical Systems, Inc. San Diego, CA 858-762-6700
Identification and Assessment of Damage to Composite Aircraft Structures Training DocumentAIR6825 (Current)8/3/2020
Individuals who complete the applicable modules aligned with this training document will be able to define the type of damage, define the extent of damage, determine if further inspection is required, evaluate the damage against published allowable damage limits, and provide accurate documentation of the damage. The intended outcome of the training is increased safety such that no aircraft is released with unknown damage and that the aircraft meets continued airworthiness requirements. The goal is to change the culture from damage discovery to damage reporting while also reducing or eliminating flight delays due to incorrect or insufficient information. Teaching levels have been assigned to the curriculum to define the knowledge, skills, and abilities graduates will need. Minimum hours of instruction have been provided to ensure adequate coverage of all subject matter including lecture and practical exercise. These minimums may be exceeded and may include an increase in the total
AMS CACRC Commercial Aircraft Composite Repair Committee
Identification and Assessment of Damage to Composite Aircraft Structures Training DocumentAIR6825-TEST-REC (Historical)8/3/2020
Individuals who complete the applicable modules aligned with this training document will be able to define the type of damage, define the extent of damage, determine if further inspection is required, evaluate the damage against published allowable damage limits, and provide accurate documentation of the damage. The intended outcome of the training is increased safety such that no aircraft is released with unknown damage and that the aircraft meets continued airworthiness requirements. The goal is to change the culture from damage discovery to damage reporting while also reducing or eliminating flight delays due to incorrect or insufficient information. Teaching levels have been assigned to the curriculum to define the knowledge, skills, and abilities graduates will need. Minimum hours of instruction have been provided to ensure adequate coverage of all subject matter including lecture and practical exercise. These minimums may be exceeded and may include an increase in the total
AMS CACRC Commercial Aircraft Composite Repair Committee
Electrically Non-Conductive Ladder Fall ProtectionTBMG-361943/1/2020
NASA’s Kennedy Space Center developed an electrically non-conductive ladder fall protection system for the Launch Complex (LC) 39B lightning towers. The towers include a 100-foot fiberglass mast at the top of the tower structure. The fiberglass masts insulate the metallic tower structure from the lightning strike protection system that is housed at the top of the fiberglass masts.
Understanding the Impact of Standardized SAE Waveform Parameter Variation on Artificial Lightning Plasma, Specimen Loading, and Composite Material Damage01-13-01-00022/18/2020
Previous works have established strategies to model artificial test lightning plasma with specific waveform parameters and use the predicted plasma behavior to estimate test specimen damage. To date no computational works have quantified the influence of varying the waveform parameters on the predicted plasma behavior and resulting specimen damage. Herein test standard Waveform B has been modelled and the waveform parameters of “waveform peak,” “rise time,” and “time to reach the post-peak value” have been varied. The plasma and specimen behaviors have been modelled using the Finite Element (FE) method (a Magnetohydrodynamic FE multiphysics model for the plasma, a FE thermal-electric model for the specimen). For the test arrangements modelled herein, it has been found that “peak current” is the key parameter influencing plasma properties and specimen damage. A 10% increase in peak current magnitude (and resulting 21% increase in action integral) results in a 12% increase in plasma peak
Millen, Scott, Murphy, Adrian, Abdelal, Gasser, Catalanotti, Giuseppe
Hardening Lightweight Metal Foams with NanocoatingTBMG-358181/1/2020
Bones are strong and stable and can cope with loads almost as well as steel. But despite their strength, they are light enough to be easily moved by humans and animals. The secret lies in the combination of a hard, exterior shell that encases a porous lattice-like network of bone tissue in the interior of the bone. This structure saves on material and reduces weight.
S400 Copper Media Interface Characteristics Over Extended DistancesAS5643/1A (Current)7/9/2019
This SAE Aerospace Standard (AS) establishes guidelines for the use of IEEE-1394-2008 Beta (formerly IEEE-1394b) as a data bus network in military and aerospace vehicles. It encompasses the data bus cable and its interface electronics for a system utilizing S400 over copper medium over extended lengths. This document contains extensions/restrictions to “off-the-shelf” IEEE-1394 standards, and assumes that the reader already has a working knowledge of IEEE-1394. This document does not identify specific environmental requirements (electromagnetic compatibility, temperature, vibration, etc.); such requirements will be vehicle-specific and even LRU-specific. However, the hardware requirements and examples contained herein do address many of the environmental conditions that military and aerospace vehicles may experience. One should refer to the appropriate sections of MIL-STD-461E for their particular LRU, and utilize handbooks such as MIL-HDBK-454A and MIL-HDBK-5400 for guidance. This
AS-1A Avionic Networks Committee
Post Lightning Strike InspectionF-0075-2019-146635/13/2019
Inspecting an aircraft after a known or suspected lightning strike can be a tedious and subjective task. While aircraft technical manuals do provide conditional inspections following a lightning strike, these inspections tend to be broad in their approach and based solely on the presence of visual damage. This paper discusses the simple technique of tracing the lightning path through the aircraft by the use of an analog magnetometer to identify ferromagnetic parts that have been magnetized by the substantial electrical current of a lightning strike. While this technique is not novel, it is not often published as an inspection technique. Knowing the approximate path of the lightning can assist aircrews and maintainers in the identification of suspect parts that may require further inspection, repair and/or replacement thereby increasing safety and ensuring continued airworthiness of the aircraft.
Massa, Travis
X-Ray Study of Low-Density MaterialsTBMG-339033/1/2019
It's hard to get an X-ray image of low-density material like tissue between bones because X-rays just pass right through like sunlight through a window. Sandia studies myriads of low-density materials, from laminate layers in airplane wings to foams and epoxies that cushion parts. So they borrowed and refined a technique from the medical field, X-ray phase contrast imaging, to look inside the softer side of things. The technique measures not just the number of X-ray photons that get through the sample, as in conventional X-ray imaging, but also the phase of the X-rays after they pass through, offering a complete look at interfaces inside a structure.
Streamlining EMC Solutions for Avionics Interfaces19AERP02_042/1/2019
Lightning strikes to jet airliners are common - about once every 1000 flight hours. The DO-160G standard, Environmental Conditions and Test Procedures for Airborne Equipment, is a standard for the environmental testing of avionics hardware. Many airplane manufacturers specify DO-160G Section 22, lightning induced transient susceptibility, as a requirement for critical systems like guidance, radars, communications, engine control, and heat and air controls. Aircraft fuselage, wing and tail flight controls, wing tips, fin tips, engine nacelles, and landing gear are the areas most likely to be hit by lightning strikes. Modern aircraft are designed with fly by wire systems for flight controls. Fly by wire means that inputs from either flight control computers or pilot manual inputs are transmitted electrically to a servomotor, which controls flight control actuators. Communication interfaces for these flight control systems can be implemented on an RS-485 physical layer. Communication
Streamlining EMC Solutions for Avionics InterfacesTBMG-337732/1/2019
Lightning strikes to jet airliners are common - about once every 1000 flight hours. The DO-160G standard, Environmental Conditions and Test Procedures for Airborne Equipment, is a standard for the environmental testing of avionics hardware. Many airplane manufacturers specify DO-160G Section 22, lightning induced transient susceptibility, as a requirement for critical systems like guidance, radars, communications, engine control, and heat and air controls. Aircraft fuselage, wing and tail flight controls, wing tips, fin tips, engine nacelles, and landing gear are the areas most likely to be hit by lightning strikes.
Plasma Generator Using Spiral ConductorsTBMG-337032/1/2019
NASA's Langley Research Center has developed a patented SansEC sensor technology for use in many different areas, including tall structures and wind turbines. The SansEC technology is a proven wireless sensing platform capable of measuring the electrical impedance of physical matter in proximity to the sensor based on a change in its resonance response. The SansEC sensor also exhibits a unique characteristic to disperse the lightning strike current to help mitigate lightning damage. In a turbine blade application, an array of SansEC sensors will cover the surface area of the composite blade, providing both lightning mitigation and damage sensing. NASA Langley is seeking industrial partners/licensees to commercialize this technology. The research team at NASA Langley is available to assist with further development.
Aircraft Lightning ZoneARP5414B (Current)12/5/2018
This SAE Aerospace Recommended Practice (ARP) defines lightning strike zones and provides guidelines for locating them on particular aircraft, together with examples. The zone definitions and location guidelines described herein are applicable to Parts 23, 25, 27, and 29 aircraft. The zone location guidelines and examples are representative of in-flight lightning exposures.
AE-2 Lightning Committee
ASSEMBLED COUPLING ENVELOPE, THREADLESS - FLEXIBLE, FIXED CAVITY, CURRENT CARRYING, SELF BONDING, ENVELOPE DIMENSIONSAS7511A (Historical)4/18/2018
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
Sequential/Simultaneous Multi-Metallized Nanocomposites (S2M2N)TBMG-2798712/1/2017
NASA Langley Research Center has developed a method to create Sequential/Simultaneous Multi-Metallized Nanocomposites (S2M2N) via supercritical fluid (SCF) sequential or simultaneous multi-metal infusion. The SCF infusion process provides deep impregnation of metal nanoparticles into a variety of materials, including those with challenging topographies and complex structures. The resulting multi-metallized nanocomposites can possess high electrical conductivity, permittivity, permeability, wear resistance/anti-penetrant, and radiation shielding along with high toughness.
Thermoplastic Fuselage DemonstratorTBMG-2766110/1/2017
Porcher Industries Badinières, France +33 (0)4 74 43 10 10
Electromagnetic Compatibility and Interference - Design Methodology, Challenges and Guidelines for Avionics Product and Systems2017-01-21189/19/2017
Avionics industry is moving towards more electric & lightweight aircrafts. Electromagnetic effects becomes significantly challenging as materials starts moving towards composite type. Traditional methods for controlling EMC will not be sufficient. This shift increases the complexity of in-flight hardware elements for EMI/EMC control. This paper discusses the need for EMI/EMC Control and brings out the analysis & applicability of various EMI/EMC standards in aerospace, commercial and industrial electronic products, provides comparative study with respect to levels. The study include various sections of DO-160 and applicable guidelines for controlling EMI/EMC with respect to LRU (Line Replaceable Unit) & wire/cable harnesses. Also presents guidelines with respect to shielding of components, selection of components, grounding schemes, filter topologies and layout considerations. It provides comparative study made for different filters, good layout examples, generic simulation examples and
Vadgaonkar, Prashant S, banik, Diptar
ASSEMBLED COUPLING ENVELOPE, THREADLESS - FLEXIBLE, FIXED CAVITY, CURRENT CARRYING, SELF BONDING, ENVELOPE DIMENSIONSAS7511 (Historical)9/7/2017
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
Rotorcraft Fastener Electrical Contact Analysis for Optimal Carbon Fiber Composite Lightning Strike ProtectionF-0073-2017-121585/9/2017
ABSTRACT In this paper we investigate the importance of electrical contact efficiency between fasteners and skin-level expanded metal mesh and how it influences lightning current energy transport. Since carbon fiber reinforced polymer composites (CFRPs) are electrically anisotropic and typically exhibit relatively low conductivities which are directionally distinct, aerospace manufacturers frequently use metallic foil layers or an expanded metal mesh on outer surfaces of composite structures for lightning strike protection. Due to irregular topology and associated micro-texture of machined holes in composites it is shown non-uniform interface surfaces between the fastener and composite layers reduces electrical continuity, thereby impeding current flow as a result of increased contact resistance levels. Furthermore, lightning strike experiments have indicated that metal mesh intimacy around the perimeter of the fastener head directly affects overall electromagnetic response of the
Liebscher, Andreas, Rizza, Gregory, Prachumsri, Wudhidham
Risks of Lightning to Automotive Occupants and Electrical/Electronic Systems2017-01-00613/28/2017
Lightning strikes on automobiles are usually rare, though they can be fatal to occupants and hazardous to electronic control systems. Vehicles’ metal bodies are normally considered to be an effective shield against lightning. Modern body designs, however, often have wide window openings, and plastic body parts have become popular. Lightning can enter the cabin of vehicles through their radio antennas. In the near future, automobiles may be integrated into the electric power grid, which will cause issues related to the smart grid and the vehicle-to-grid concept. Even today, electric vehicles (EVs) and plug-in hybrid vehicles (PHEVs) are charged at home or in parking lots. Such automobiles are no longer isolated from the power grid and thus are subject to electric surges caused by lightning strikes on the power grid. A charging system connected to an EV or PHEV should absorb the surge, but powerful lightning strikes can overwhelm the surge protection and intrude into the electric and
Alkhteeb, Sultan A.M, Oho, Shigeru, Nagashima, Yuki, Nishimura, Seisuke, Shimizu, Hiroyuki
Lightning Protection and Detection SystemTBMG-261551/1/2017
NASA’s Langley Research Center has developed a sensor technology for structural health monitoring on composite aircraft surfaces. When conventional aircraft are struck by lightning, the result can range from no damage to serious damage requiring extensive repairs that can take the airplane out of service for an extended period of time. The SansEC technology is a proven wireless sensing platform capable of measuring the electrical impedance of physical matter in proximity to the sensor based on a change in its resonance response. The sensor also exhibits a unique characteristic to disperse the lightning strike current to help mitigate lightning damage. In this application, an array of SansEC sensors will cover a selective area of the aircraft surface, providing both mitigation and damage sensing.
Electric Field Quantitative Measurement System and MethodTBMG-261391/1/2017
NASA Langley Research Center’s Electric Field Imaging (EFI) system is the only noncontact method capable of quantitatively measuring the magnitude and direction of electrostatic fields in near- and far-field applications. Based on low-cost, commercially available components, the EFI system uses measurement of very-low-current, human-safe electric fields to construct a three-dimensional image of objects and people based on their dielectric properties. This platform technology, originally developed for measurement of the efficacy of electrical shielding around cables, could be optimized for a variety of applications, including medical imaging, security and detection, weather and natural disaster prediction, and nondestructive evaluation of composites and insulators. The EFI system has the potential to offer a lower-cost, portable, and safer alternative to the imaging systems currently used in these applications.
A Suitable Platform for Storm Penetration, Risk Analysis for the SPA-10 Aircraft Modification2016-01-20439/20/2016
The SPA-10 project, sponsored by U.S. National Science Foundation, is to acquire and qualify a replacement for the retired T-28 “storm penetration” aircraft previously used to acquire meteorological data to enable understanding and modelling of mid-continent thunderstorms. The National Science Foundation selected the Fairchild A-10 (bailed from the U.S. Air Force) as the platform to be adapted to perform the storm penetration mission to altitudes of eleven kilometers, and funded Naval Postgraduate School’s Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) as prime contractor. An expert panel conducted a review of the SPA-10 project in 2014 and recommended a risk analysis addressing hazards to the aircraft and pilots, such as icing, hail, turbulence and lightning. This paper presents the results of the risk analysis performed in response to this need, including recommended mitigations. In general the A-10 aircraft systems and structure were shown to be robust and
Millar, Richard C., Mazzuchi, Thomas, Jonsson, Haflidi
Aerospace & Defense Technology: June 201616AERP066/1/2016
Digital Design Tools Simulating Thermal Expansion in Composites with Expanded Metal Foil for Lightning Protection Rugged Computing Designing VME Power Systems with Standard Modules Optical Sensors Optical Ice Sensors for UAVs Rotorcraft Technology Rotorcraft Icing Computational Tool Development RF & Microwave Technology Curled RF MEMS Switches for On-Chip Design: Design Software Supports BAE System's Mixed-Signal Chip Design
Dual-Use Structures: Composite Wing with Structural Antenna ApertureF-0072-2016-115525/17/2016
Many modern aircraft, including rotorcraft, require conformal antennas and fairings to reduce wind drag, ice accretion, lightning strikes, and impact damage. An innovative composite wing configuration with a structural Ultra High Frequency (UHF) antenna window "aperture" has been developed. The wing is based on variants of lightweight X-Cor® sandwich core technology for durability and damage tolerance, with tailored electromagnetic properties in the aperture region of the wing. This paper presents a brief introduction to helicopter wings, a summary of recent research at Boeing and Army leading to this design, and the development approach used for this project. Structural and electromagnetic analyses are provided, and measurement results of an early prototype are summarized. The emphasis of this paper is on the wing configuration details surrounding the antenna aperture. The approach can be replicated on almost any current or future aircraft or rotorcraft.
Tyrell, Stacey, Robeson, Mark, Kube, Courtney, McCarthy, Dennis, Lavin, Ronald
Imager Maps Cell Composition in 3DTBMG-2360012/16/2015
An instrument built at Colorado State University lets scientists map cellular composition in three dimensions, at the nanoscale. Researchers are able to watch how cells respond to new medications at the most minute level ever observed.
Lightweighting Focus for TE's Connectivity SolutionsTBMG-2313510/1/2015
TE Connectivity recently announced two new aerospace connectivity solutions that offer substantial weight savings: its COPALUM Lite sealed terminals and splices, and its Raychem INSTALITE lightweight braid system.
Aerospace - Lightning Effects on Hydraulic Transport Elements on AircraftAIR6185 (Historical)8/28/2015
This SAE Aerospace Information Report (AIR) describes hydraulic system design and installation to minimize the effects of lightning, especially when the aircraft structure is composite. Techniques for effective electrical bonding, hydraulic system lightning protection, and lightning protection verification techniques are discussed.
A-6A1 Commercial Aircraft Committee
Fiber-Optic Sensor for Aircraft and Structure Lightning MeasurementTBMG-224297/1/2015
An optical-fiber sensor based on Faraday Effect was developed for measuring total lightning current. Designed for aircraft installation, it is lightweight, non-conducting, structure conforming, and is immune to electromagnetic interference, hysteresis, and saturation. It can also be used on windmills, lightning towers, and can help validate lightning detection network measurements.
Aircraft In Situ Validation of Hydrometeors and Icing Conditions Inferred by Ground-based NEXRAD Polarimetric Radar2015-01-21526/15/2015
MIT Lincoln Laboratory is tasked by the U.S. Federal Aviation Administration to investigate the use of the NEXRAD polarimetric radars* for the remote sensing of icing conditions hazardous to aircraft. A critical aspect of the investigation concerns validation that has relied upon commercial airline icing pilot reports and a dedicated campaign of in situ flights in winter storms. During the month of February in 2012 and 2013, the Convair-580 aircraft operated by the National Research Council of Canada was used for in situ validation of snowstorm characteristics under simultaneous observation by NEXRAD radars in Cleveland, Ohio and Buffalo, New York. The most anisotropic and easily distinguished winter targets to dual pol radar are ice crystals. Accordingly, laboratory diffusion chamber measurements in a tightly-controlled parameter space of temperature and humidity provide the linkage between shape and the expectation for the presence/absence of water saturation conditions necessary for
Williams, Earle, Donovan, Michael F., Smalley, David J., Hallowell, Robert G., Griffin, Elaine P., Hood, Kenta T., Bennett, Betty J., Wolde, Mengistu, Korolev, Alexei V.
Dual-Use Structures: Apache Empennage Integral Driveshaft Cover AntennaF-0071-2015-102515/5/2015
ABSTRACT Many modern aircraft, including rotorcraft, require conformal antennas and fairings to reduce wind drag, ice accretion, lightning strikes, and impact damage. An innovative approach to embedding Very High Frequency (VHF) antenna elements in the leading and trailing edges of a helicopter empennage has been developed. A prototype has been fabricated and tested on a mockup of a helicopter empennage, consisting of the vertical stabilizer (tail), horizontal stabilator, and gearbox. Testing has shown that the design can meet typical communications range requirements. A history of helicopter empennage antennas, the development approach, design features and key innovations, and measured results are presented and discussed. The approach can be replicated on almost any current or future aircraft or rotorcraft.
Lavin, Ronald, Pyle, Glenn, Robeson, Mark, McCarthy, Dennis
RotorShield Advanced Rotor Blade Erosion Protection, Application to V-22F-0071-2015-102575/5/2015
ABSTRACT Rotorcraft operating in desert and shore environments continue to experience severe rotor blade erosion. To mitigate damage from sand and rain, rotor blade leading edges have historically been designed with a metallic abrasion strip that serves as sacrificial material to absorb the damage. Erosion of the metal abrasion strip can become a major contributor aircraft downtime and maintenance activities. Sand erosion takes place during takeoff and landing, or during ground operations where dust, sand, and other debris are lifted by the rotor downwash. Rain erosion occurs during aircraft operation in heavy rainfall. To alleviate the maintenance costs associated with rotor erosion, a number of research efforts have investigated alternative rotor blade abrasion strip treatments to develop new structures or coatings that are more resistant to erosion damage. The ONR RotorShield erosion coating system is a technology applied to the V-22 to enable extended erosion protection and
Nissen, Jeffrey, Holemans, Peter, Venezia, Jonathan
NASA Launch Pads Protected Against Lightning-Induced Power SurgesTBMG-2066810/1/2014
Circuit protection components Littelfuse Chicago, IL 773-628-1000
KSC Spaceport Weather Data ArchiveTBMG-198926/1/2014
The Spaceport Weather Data Archive provides a fully searchable database of weather data gathered at Kennedy Space Center and the Cape Canaveral Air Force Station. Weather data includes wind, temperature, and humidity data from a surface meteorological tower network; upper air soundings from both weather balloons and radar wind profilers; and data from the extensive rain gauge network. Not only can the user easily retrieve data and download it, but the user can also view graphically the weather data on a map overlay. For example, the user can enter search criteria to view all lightning strikes ending at a particular date/time, and graphically see the lightning strikes color-coded based on elapsed time for the prior seven hours. A unique feature of the software is the capability to invoke an automated playback for cloud-to-ground lightning events on a geographic overlay for a selected date and time interval.
LED DriversTBMG-196535/1/2014
SL Power Electronics (Ventura, CA) has introduced its new LE Series of LED drivers. Available in 10 models from 75 to 300 watts, the constant current LED drivers enable highly efficient LED lighting for applications that require more than eight hours per day of operating life. Featuring a wide input voltage range of 90 to 305 VAC, up to 95 percent efficiency and the ability to survive lightning strikes, the LE-Series have UL 8750 and EN61347 safety approvals with an IP67 rating and are housed in a waterproof metal case in order to withstand hot and cold temperatures in outside installations.
Aerospace & Defense Technology: February 201414AERP022/3/2014
Thermal simulation and testing of expanded metal foils for lightning protection With the implementation of major aircraft structures fabricated from carbon fiber reinforced plastic materials, lightning protection has become a more complicated issue for designers and engineers to solve. Electronics take charge Digital controls are handling more engine control tasks on a wider range of aircraft.
Aerospace - Testing of Electromechanical Actuators, General Guidelines ForARP5724 (Current)10/4/2013
This document provides an overview of the tests, and issues related to testing, that are unique to Electromechanical Actuators (EMAs). The tests, and issues documented, are not necessarily all-inclusive. This document discusses both the tests applicable to EMAs and the test methodologies to accomplish the test objectives. EMAs may be used in a wide variety of applications such as utility, secondary flight controls and primary flight controls, in a wide variety of markets including manned and unmanned civil and military aircraft, small missile fin and thrust vector control applications up to high powered utility and flight controls. EMAs may also have either a rotary or a linear output, be servo controlled or use simple open loop point-to-point or other control topologies. As such this document covers a wide range of potential applications, the application of any given test requirement is determined by the application and the user. This document attempts to provide basic guidance on
A-6B3 Electro-Mechanical Actuation Committee
More About Lightning Induced Effects on Systems in a Composite Aircraft2013-01-21569/17/2013
In order to guarantee systems immunity, lightning induced electromagnetic energy has to be lower than the system's susceptibility threshold. This can be achieved, if the aircraft structure provides a good protection against lightning current as well as against its electromagnetic induced field. Moreover such a structure is also required to constitute a ground plane that guarantees very low common mode impedance between all grounded systems in order to keep them at the same electrical potential. The interaction of lightning with aircraft structure, and the coupling of induced energy with harnesses and systems inside the airframe, is a complex phenomenon, mainly for composite aircraft. Composite structures are either not conductive at all (e.g., fiberglass) or are significantly less conductive than metals (e.g., carbon fiber). Consequently, current from a lightning strike will not linger long time on aircraft skin (outside) but will enter the structure and seek metal paths available to
Moupfouma, Fidele, Tse, William, Jalali, Mohsen
Thermal Simulation and Testing of Expanded Metal Foils Used for Lightning Protection of Composite Aircraft Structures2013-01-21329/17/2013
Since the 1960's, lightning protection of aircraft has been an important design aspect, a concern for the flying public, aircraft manufacturers and the Federal Aviation Administration (FAA). With the implementation of major aircraft structures fabricated from carbon fiber reinforced plastic (CFRP) materials, lightning protection has become a more complicated issue to solve. One widely used material for lightning strike protection of CFRP structures within the aerospace industry is expanded metal foil (EMF). EMF is currently used in both military and commercial passenger aircraft. An issue that has historically been an area of concern with EMF is micro cracking of paint on the composite structure which can result in corrosion of the metal foil and subsequent loss of conductivity. This paper addresses the issues of stress and displacement in the composite structure layup which contribute to paint cracking caused by aircraft thermal cycling. The analysis of EMF by computer modeling is
Morgan, Jeffrey
Aircraft Structure Paint Thickness and Lightning Swept Stroke Damages2013-01-21359/17/2013
During its flight an aircraft can be struck by lightning and the induced high current will require a highly conductive airframe skin structure in order for it to propagate through with minimum damage. However an aircraft skin is generally coated with paint and the airframer does not always have control on the paint thickness. Paint thickness generates heightened concerns for lightning strike on aircraft, mainly because most of coatings dedicated to that purpose are non-conductive. Using insulating material or non-conductive coating with certain thickness may contribute to or increase damage inflicted by the swept stroke lightning energy, even on metallic structures Due to its high relative permittivity, a non-conductive paint or coating on a fuselage skin surface will contribute to slow down the lightning current propagation through structure. With this comes the risk of increasing heat that will favor structural damage and possible melt through. The correlation between paint thickness
Moupfouma, Fidele
Electromagnetic Protection Hazards on Composite versus Metallic Aircraft2013-01-21579/17/2013
The lightning represents a fundamental threat to the proper operation of aircraft systems. For aircraft protection, Electromagnetic Compatibility requires conductive structure that will provide among all, electromagnetic shielding and protection from HIRF and atmospheric electricity threat. The interaction of lightning with aircraft structure, and the coupling of induced energy with harnesses and systems inside the airframe, is a complex subject mainly for composite aircraft. The immunity of systems is governed by their susceptibility to radiated or conducted electromagnetic energy. The driving mechanism of such susceptibility to lightning energy is the exposure to the changing magnetic field inside the aircraft and IR voltage produced by the flow of current through the structural resistance of the aircraft. The amplitude of such magnetic field and IR voltage is related to the shielding effectiveness of the aircraft skin (wiremesh, composite conductivity). However, it is also known
Moupfouma, Fidele, Klim, Zdzislaw, Skorek, Adam
Electromagnetic Compatibility (EMC) System Design ChecklistAIR1221 (Current)2/24/2013
This checklist is to be used by project personnel to assure that factors required for adequate system electromagnetic compatibility are considered and incorporated into a program. It provides a ready reference of EMC management and documentation requirements for a particular program from preproposal thru acquisition. When considered with individual equipments comprising the system and the electromagnetic operational environment in which the system will operate, the checklist will aid in the preparation of an EMC analysis. The analysis will facilitate the development of system-dependent EMC criteria and detailed system, subsystem, and equipment design requirements ensuring electromagnetic compatibility.
AE-4 Electromagnetic Compatibility (EMC) Committee
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