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Training / Education

AS9100D Internal Auditor Training

2024-10-28
Internal audits are a requirement of the AS9100, AS 13100 and RM 13005 and are intended to verify the compliance and effectiveness of an organization's quality management system. The methods and techniques for performing internal audits have significantly changed in the aviation, space and defense industries, and internal auditors must be knowledgeable of these requirements and the expectations as identified in the standard.
Training / Education

Vehicle Crash Reconstruction Principles and Technology

2024-09-17
Crash reconstruction is a scientific process that utilizes principles of physics and empirical data to analyze the physical, electronic, video, audio, and testimonial evidence from a crash to determine how and why the crash occurred. This course will introduce this reconstruction process as it gets applied to various crash types - in-line and intersection collisions, pedestrian collisions, motorcycle crashes, rollover crashes, and heavy truck crashes. Methods of evidence documentation will be covered. Analysis methods will also be presented for electronic data from event data recorders and for video.
Training / Education

Aircraft Cabin Safety and Interior Crashworthiness

2024-07-23
This two-day course will begin with a discussion of commercial off the shelf (COTS) test requirements.  The instructor will then guide participants through the various cabin interior emergency provisions and their requirements such as supplemental passenger oxygen, emergency equipment, seats, flammability, emergency exits, emergency lighting and escape path markings, and various other cabin interior systems.  
Technical Paper

Current and Torque Harmonics Analysis of Triple Three-Phase Permanent-Magnet Synchronous Machines with Arbitrary Phase Shift Based on Model-in-the-Loop

2024-07-02
2024-01-3025
Multiple three-phase machines have become popular in recent due to their reliability, especially in the ship and airplane propulsions. These systems benefit greatly from the robustness and efficiency provided by such machines. However, a notable challenge presented by these machines is the growth of harmonics with an increase in the number of phases, affecting control precision and inducing torque oscillations. The phase shift angles between winding sets are one of the most important causes of harmonics in the stator currents and machine torque. Traditional approaches in the study of triple-three-phase or nine-phase machines mostly focus on specific phase shift, lacking a comprehensive analysis across a range of phase shifts. This paper discusses the current and torque harmonics of triple-three-phase permanent magnet synchronous machines (PMSM) with different phase shifts. It aims to analyze and compare the impacts of different phase shifts on harmonic levels.
Technical Paper

Choosing the Best Lithium Battery Technology in the Hybridization of Ultralight Aircraft

2024-06-12
2024-37-0017
Many research centers and companies in general aviation have been devoting efforts to the electrification of propulsive plants to reduce environmental impact and/or increase safety. Even if the final goal is the elimination of fossil fuels, the limitations of today's battery in terms of energy and power densities suggest the adoption of hybrid-electric solutions that combine the advantages of conventional and electric propulsive systems, namely reduced fuel consumption, high peak power, and increased safety deriving from redundancy. Today, lithium batteries are the best commercial option for the electrification of all means of transportation. However, lithium batteries are a family of technologies that presents a variety of specifications in terms of gravimetric and volumetric energy density, discharge and charge currents, safety, and cost.
Technical Paper

CFD Methodology Development to Predict Lubrication Effectiveness in Electromechanical Actuators

2024-06-01
2024-26-0466
Electromechanical actuators (EMAs) play a crucial role in aircraft electrification, offering advantages in terms of aircraft-level weight, rigging and reliability compared to hydraulic actuators. To prevent backdriving, skewed roller braking devices called "no-backs" are employed to provide braking torque. These technology components are continuing to be improved with analysis driven design innovations eg. U.S. Pat. No. 8,393,568. The no-back mechanism has the rollers skewed around their own transverse axis that allow for a combination of rolling and sliding against the stator surfaces. This friction provides the necessary braking torque that prevents the backdriving. By controlling the friction radius and analyzing the Hertzian contact stresses, the brake can be sized for the desired duty cycle. No-backs can be configured to provide braking torque for both tensile and compressive backdriving loads.
Technical Paper

Aerospace Vehicle Motion Simulation with Real-Time Telemetry Data

2024-06-01
2024-26-0483
In any aerospace mission, after the vehicle has taken off, the visual is lost and the information about its current state is only through the sensor data telemetered in real-time. Very often, this data is difficult to perceive and analyze. In such cases, a 3D, near to real representation of the data can immensely improve the understanding of the current state of mission and can aid in real-time decision making if possible. Generally, any aerospace vehicle carries onboard an inertial system along with other sensors, which measures the position and attitude of the vehicle. This data is communicated to ground station. The received telemetry data is encoded as bytes and sent as packets through the network using the Universal Datagram Protocol (UDP).  The transmitted data is often available in a very low frequency, which is not desirable for a smooth display. It is therefore necessary to interpolate the data between intervals based on the time elapsed since last rendered frame.
Technical Paper

Deep Learning-Based Digital Twining Models for Inter System Behavior and Health Assessment of Combat Aircraft Systems

2024-06-01
2024-26-0478
Modern combat aircraft demands efficient maintenance strategies to ensure operational readiness while minimizing downtime and costs. Innovative approaches using Digital Twining models are being explored to capture inter system behaviours and assessing health of systems which will help maintenance aspects. This approach employs advanced deep learning protocols to analyze the intricate interactions among various systems using the data collected from various systems. The research involves extensive data collection from sensors within combat aircraft, followed by data preprocessing and feature selection, using domain knowledge and correlation analysis. Neural networks are designed for individual systems, and hyper parameter tuning is performed to optimize their performance. By combining the outputs of these during the model integration phase, an overall health assessment of the aircraft will be generated.
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