Flight Instrument Research Articles

O Layout do Painel do C-130 Modernizado e sua Influência na Operação Segura da Aeronave:

The automation technology found in Aviation a fertile field for its development. This development reached the Brazilian Air Force C-130 aircraft through the modernization program of the ten aircraft acquired from the Italian Air Force, with its beginning in 2005. The objective of this study was to determine whether the modernization of the C-130 meets the ergonomic principles for a perfect human-computer interaction, aiming mainly at the safe operation of aircraft, and considering the piloting or the pilot as the main factor in the cause of accidents. In order to achieve this goal, we adopted a descriptive methodology, through desk research and literature. Through a thorough theoretical study on the subject, it was possible to evaluate the ergonomic influence based on two aspects: the suitability of the position of EFIS control panel for the pilot, under instrument flight, and adequacy of the position of the backup instruments. To do that, the equipment incorporated in the aircraft for modernization were described, detailing their role and location in the cabin. Data on ergonomic factors related to automation and the flight were also collected, in order to seek a well-designed cockpit and the problems that may occur if that is not observed. In these two devices, probable loss of situational awareness and the appearance of visual illusions or spatial disorientation in the pilot were identified. These points were listed and discussed as a contribution to the operators of the aircraft and the other Brazilian Air Force squadron passing through the same process.

Impact of automation level on airline pilots' flying performance and visual scanning strategies: A full flight simulator study.

Cockpit automation has brought significant benefits in terms of mental workload and fatigue. However, the way primary flight instruments are monitored by pilots may be negatively affected by the high confidence in systems. We examined the effects of automation level on mental workload, manual flight performance and visual strategies. Twenty professional pilots performed six landing scenarios at three levels of automation depending on flight director (flight path guidance) and autothrust (automatic management of the speed) engagements. Higher levels of automation increased flight performance and reduced mental workload, but were associated with a decrease in vigilance to primary instruments, particularly flight path indicators and engines' thrust. We also found that gaze entropy was sensitive to pilot role (pilot flying vs pilot monitoring) and automation level. These results confirmed the risks of adverse effects of automation on visual monitoring. Designing procedures for pilots to actively monitor automated cockpit systems should be encouraged.

Computational Algorithms for Representing Aircraft Instruments with Barometric Physics (Numerical Methods Applied to Flight Simulation)

The present work describes the development of a graphical environment to represent typical flight instruments on a computer screen. The instruments’ behavior is displayed according to information regarding the aircraft’s flight conditions. Some of the instruments represented in this work, such as the altimeter, the vertical speed indicator, the aircraft speed indicator, and the Mach indicator, use air pressure principles. The algorithms and routines developed for the screen display are created using the C++ programming language and compiled independently to be included as libraries to improve the software performance. The algorithms developed for this purpose also include the corresponding relationship between the physical variables, such as the speed and displacement, and the standard atmosphere to provide an equivalent value. These algorithms are successfully tested using data information to simulate three hypothetical flights, which are divided into maneuvers with the aircraft in a stopped position, running on the ground, taking off and flying away, including some changes in directions. Moreover, the routines for displaying the aircraft path with the instruments’ animation are also successfully tested by comparison. Finally, an approach analysis as a function of the step time (Δt) used for calculation of the aircraft displacement to evaluate the efficiency of the numerical method integrated in the simulator is also described. It is proved that the aircraft instrument representation is appropriate according to the input data of the analyzed flights, and an improvement in the calculation can be easily obtained, making it possible to represent any flight condition on the aircraft instruments.

Multi-facial freeform monolith optics for astronomical and space applications

The utilization of a multi-facial freeform monolithic (MFFM) component in a compact Cassegrain configuration design offers unprecedented capabilities to accommodate various next-generation science instruments. The concept of the MFFM component can be employed for applications in telescopes working at ultra-violet, optical, infrared, terahertz, microwave, and even radio frequencies. MFFM finds its scope in space optical and astronomical systems where the risks are associated with the alignment, manufacturability, and maintaining large-sized apertures, large number of components, cost, and volume of the flight optical terminals and instruments. The current challenges faced at the manufacturing phase of MFFM are the precision positioning of each surface concerning the optical axis and maintaining the required edge thickness. This paper presents the optical design, fabrication, measurement, and in-laboratory characterization of MFFM. The results of a prototyping effort through ultra-precision single-point diamond turning (SPDT) and coating demonstrate the feasibility of producing these elements as per size and weight requirements. The experimental results show excellent surface qualities in terms of nanometric surface roughness and close-to-submicron form accuracy on each surface of the freeform monolith. Focusing performance and imaging performance are carried out to validate the designed and manufactured precision component. The main contribution is highlighted in terms of the optimized fabrication process for producing the precision MFFM for a fast optical system while balancing the alignment errors. The demonstrated research work highlights the intriguing possibilities of the monolith and creates new avenues for research in domains that use huge optical systems, such as astrophysical study, planetary observation, earth monitoring, and geosciences.

Use of Attitude and Heading Reference System (AHRS) to Analyze the Impact of Safety Nets on the Accelerations Occurring in the Human Body During a Collision.

The article presents accelerations occurring in the human body when falling onto a safety net. An attitude and heading reference system (AHRS) consists of sensors on three axes that provide attitude information for objects, including pitch, roll, and yaw. These sensors are made of microelectromechanical systems (MEMS) gyroscopes, accelerometers, and magnetometers. Usually, they are used in aircraft flight instruments due to their high precision. In the present article, these sensors were used to test safety nets, protecting people or objects falling from heights. The measurement was made for two heights: 6 m and 3.5 m. During the research, a type of mannequin that is a representative model of the human body for the largest segment of the adult population was used. The measurement was carried out using two independent measurement systems. One recorded the accelerations at the chest of the tested object, while the sensors of the second system were placed at the head, arms, and legs. The compiled measurement results were related to the permissible acceleration values that do not threaten human health and life.

Numerical Simulation Study on Predicting the Critical Icing Conditions of Aircraft Pitot Tubes.

Aircraft pitot tubes are sophisticated instruments designed to detect airflow pressure and relay this information to onboard computers and flight instruments, enabling the calculation of airspeed through the measurement of total-static pressure differences. The formation of ice on aircraft pitot tubes can compromise the acquisition of airspeed data, misguide pilots, and potentially cause catastrophic flight control failures. This article introduces a predictive methodology for identifying critical conditions that lead to icing on aircraft pitot tubes. Utilizing numerical simulation techniques, the methodology calculates the critical conditions for pitot tube icing across cruise flight regimes and atmospheric conditions, resulting in the generation of a critical condition envelope surface. By comparing these critical conditions against actual sensor data, a predictive danger zone can be established, offering an advanced warning system to ensure flight safety.

Research on Runway Capacity Evaluation of General Aviation Airport Based on Runway Expansion System

To enhance the operational management capabilities of general aviation airports, this paper proposes a method for evaluating the runway capacity of general aviation airports based on the runway expansion system. Firstly, it provides a brief introduction to the flight rules of general aviation airports and arrival and departure flight procedures with symmetrical characteristics, which serve as a theoretical basis for establishing the runway expansion system. Subsequently, a runway expansion system that covers symmetrical flight activities such as departure and arrival under a visual flight rule and an instrument flight rule is proposed, providing a conceptual model for evaluating the runway capacity of general aviation airports. On this foundation, the classical space–time analysis model is improved to establish a single runway arrival, departure, and mixed operation capacity evaluation model for general aviation airports. Finally, the reliability and rationality of this method are verified through case evaluations and three sets of numerical experiments with symmetrical relationships. The experiments demonstrate that this method can better reflect the actual conditions of the runways at general aviation airports while ensuring flight safety, and it can provide a reference for related research.

Investigating the chemical space coverage of multiple chromatographic and ionization methods using non-targeted analysis on surface and drinking water collected using passive sampling

Multiple non-targeted analysis tools were used to look for a broad range of possible chemical contaminants present in surface and drinking water using liquid chromatography separation and high-resolution mass spectrometry detection, including both quadrupole time of flight (Q-ToF) and Orbitrap instruments. Two chromatographic techniques were evaluated on an LC-Q-ToF with electrospray ionization in both positive and negative modes: (1) the traditionally used reverse phase C18 and (2) the hydrophilic interaction liquid chromatography (HILIC) aimed to capture more polar contaminants that may be present in water. Multiple ionization modes were evaluated with an LC-Orbitrap, including electrospray (ESI) and atmospheric pressure chemical ionization (APCI), also in both positive and negative modes. A suspect screening library of over 1300 possible environmental contaminants, including pesticides, pharmaceuticals, personal care products, illicit drugs/drugs of abuse, and various anthropogenic markers was made with experimentally collected data with the LC-Q-ToF with both column types, with 227 chemicals being retained by the HILIC column. The non-targeted methods using multiple chromatographic and ionization modes were applied to environmental water samples collected with polar organic chemical integrative samplers (POCIS), including surface water upstream and downstream from wastewater effluent discharge, and the downstream drinking water intake and treated drinking water for three distinct sampling events. For the LC-Q-ToF, 442 chemical features were detected on the C18 column and 91 with the HILIC column in the POCIS extracts, while 556 features were found on the Orbitrap workflow by ESI and 131 features detected by APCI. Over 100 chemicals were tentatively identified by suspect screening and database searching. The comprehensive and systematic evaluation of these methods serve as a step in characterizing the chemical space covered when utilizing different chromatography and ionization methods, or different instrument workflows on complex environmental mixtures.

Validation of a Motion Sickness Prediction Model via Flight Tests on DLR’s Bo-105 Helicopter

In previous work, a motion sickness prediction model aimed at vertical lift applications was developed. To validate this model, flight tests with an MBB Bo-105 Helicopter owned and operated by the DLR were conducted. In total, 32 test subjects were flown in 16 sorties on 30 min sinusoidal flight paths of various frequencies. The test design and implementation included the development of a suitable measurement flight instrumentation, auditive cueing systems for accurate following of the test trajectory, and questionnaires for recording motion sickness during flight. The results are analyzed, and it is shown that the previously developed motion sickness prediction model agrees well with the motion sickness observed during flight in the case of medium motion sickness.

A Survey of Medical Visualization Through the Lens of Metaphors.

We provide an overview of metaphors that were used in medical visualization and related user interfaces. Metaphors are employed to translate concepts from a source domain to a target domain. The survey is grounded in a discussion of metaphor-based design involving the identification and reflection of candidate metaphors. We consider metaphors that have a source domain in one branch of medicine, e.g., the virtual mirror that solves problems in orthopedics and laparoscopy with a mirror that resembles the dentist's mirror. Other metaphors employ the physical world as the source domain, such as crepuscular rays that inspire a solution for access planning in tumor therapy. Aviation is another source of inspiration, leading to metaphors, such as surgical cockpits, surgical control towers, and surgery navigation according to an instrument flight. This paper should raise awareness for metaphors and their potential to focus the design of computer-assisted systems on useful features and a positive user experience. Limitations and potential drawbacks of a metaphor-based user interface design for medical applications are also considered.

Experimental evaluation of wind turbine wake turbulence impacts on a general aviation aircraft

Abstract. Continued development of wind farms near populated areas has led to rising concerns about the potential risk posed to general aviation aircraft when flying through wind turbine wakes. There is an absence of experimental flight test data available with which to assess this potential risk. This paper presents the results of an instrumented flight experiment in which a general aviation aircraft was flown through the wake of a utility-scale wind turbine at an operating wind farm. Wake passes were flown at different downwind distances from the turbine, and data were collected on the orientation disturbances, altitude and speed deviations, and acceleration loads experienced by the aircraft. Videos and pilot statements were also collected, providing qualitative information about the disturbances encountered in the wake. Results show that flight disturbances were small in all cases, with no difference observed between flight data inside and outside the wake at distances greater than six rotor diameters from the turbine. At distances closer than six rotor diameters, small load factor and orientation disturbances were noted but were commensurate with those experienced in light or moderate atmospheric turbulence. Overall, the loads and disturbances experienced were far smaller than those that would risk causing loss of control or structural damage.

Artemis I Versus Wind-Tunnel Buffet-Induced Forces and Structural Responses

This paper presents comparisons of buffet forcing functions (BFFs) and associated structural responses for the Space Launch System from two data sources: 1) Artemis I (AR01) Developmental Flight Instrumentation (DFI) and 2) transonic wind-tunnel (WT) tests. Failures of DFI sensors prevented the development of a complete set of flight-based BFFs, where each BFF is based on azimuthal integration over 360 deg of unsteady pressures acquired by sensor rings placed at many longitudinal stations along the vehicle. Instead, a set of equivalent flight- and WT-based BFFs was developed based on functional DFI and WT sensors that share the same locations. Root-mean-square (rms) levels of equivalent BFFs from flight and WT data are in-family for most of the cardinal Mach numbers. However, at stations downstream of the solid rocket booster (SRB) forward attachment (FA) protuberance, the rms of flight-based BFFs exceeds their WT counterparts. Strikingly, vortex shedding off the FA protuberance occurs at lower frequencies during flight than in WT experiments. This frequency shift propagates onto the spectrum of flight-measured versus WT-based structural responses. As a result of this frequency mismatch, at certain AR01 vortex shedding frequencies, the flight responses are an order of magnitude higher than their WT-based counterparts. Thus, at AR01 vortex shedding frequencies, the WT-based BFFs do not provide an accurate estimation of the flight environments. Away from AR01 vortex shedding frequencies, the AR01-based responses are within or sometimes exceed a range of WT-based responses. This observation indicates that, outside of frequencies that are impacted by vortex shedding, the WT-based BFFs are fairly well representative of the flight environments.

The Use of Computational Algorithms to Display the Aircraft Instruments That Work with Gyroscopic and Magnetic Physics (Theory for Programming an Elementary Flight Simulator)

The Use of Computational Algorithms to Display the Aircraft Instruments That Work with Gyroscopic and Magnetic Physics (Theory for Programming an Elementary Flight Simulator)

SuperBIT Superpressure Flight Instrument Overview and Performance: Near-diffraction-limited Astronomical Imaging from the Stratosphere

SuperBIT was a 0.5 m near-UV to near-infrared wide-field telescope that launched on a NASA superpressure balloon into the stratosphere from New Zealand for a 45-night flight. SuperBIT acquired multiband images of galaxy clusters to study the properties of dark matter using weak gravitational lensing. We provide an overview of the instrument and its various subsystems. We then present the instrument performance from the flight, including the telescope and image stabilization system, the optical system, the power system, and the thermal system. SuperBIT successfully met the instrument’s technical requirements, achieving a telescope pointing stability of 0.″34 ± 0.″10, a focal plane image stability of 0.″055 ± 0.″027, and a point-spread function FWHM of ∼0.″35 over 5-minute exposures throughout the 45-night flight. The telescope achieved a near-diffraction-limited point-spread function in all three science bands (u, b, and g). SuperBIT served as a pathfinder to the GigaBIT observatory, which will be a 1.34 m near-UV to near-infrared balloon-borne telescope.

High‐Efficiency Multilevel Phase Lenses with Nanostructures on Polyimide Membranes

AbstractThe emergence of planar meta‐lenses on flexible materials has profoundly impacted the long‐standing perception of diffractive optics. Despite their advantages, these lenses still face challenges in design and fabrication to obtain high focusing efficiency and resolving power. A nanofabrication technique is demonstrated based on photolithography and polyimide casting for realizing membrane‐based multilevel phase‐type Fresnel zone plates (FZPs) with high focusing efficiency. By employing advantageous techniques, these lenses with nanostructures are directly patterned into thin polyimide membranes. The computational and experimental results have indicated that the focusing efficiency of these nanostructures at the primary focus increases significantly with increasing the number of phase levels. Specifically, 16‐level phase lenses on a polyimide membrane can achieve a focusing efficiency of more than 91.6% of the input signal (9.5 times better than that of a conventional amplitude‐type FZP) and focus light into a diffraction‐limited spot together with very weak side‐lobes. Furthermore, these lenses exhibit considerably reduced unwanted diffraction orders and produce extremely low background signals. The potential impact of these lenses extends across various applications and techniques including microscopy, imaging, micro‐diffraction, remote sensing, and space flight instruments which require lightweight and flexible configurations.

Cognitive load assessment for cadet pilots in simulated aircraft environment-pilot study

PurposeThis study aims to propose a methodology aimed at understanding the cognitive and physiological processes inherent in cadet pilot operations. Through analyzing responses from two cadet pilots with varied experience levels across diverse simulation scenarios, the research uses descriptive statistics, t-test, one-way ANOVA and percentage change analysis to explore crucial variables, including heart rate (HR), heart rate variability (HRV) and respiratory rate (RR).Design/methodology/approachThe investigation meticulously examines HR, HRV and RR under circumstances encompassing resting state, visual flight rules and instrument flight rules with engine failure. Pilots undergo comprehensive analyses employing statistical techniques and visual representations to comprehend cognitive loads and physiological adaptations.FindingsSignificant disparities emerge between the two pilots, elucidating the profound impact of experience on cognitive and physiological outcomes. Novice cadet pilots exhibit heightened variability during scenario transitions, while experienced cadet pilot demonstrate controlled responses, indicative of adaptability. Visual flight simulations evoke distinct responses, whereas instrument-based scenarios, particularly those simulating emergencies, lead to pronounced physiological changes.Practical implicationsThe findings of this research hold practical significance in introducing the proposed novel methodology for monitoring Cadet pilots to refine pilot training simulation protocols and enhance aviation safety by illuminating the interplay between experience levels and scenario complexities.Originality/valueThis study proposes a novel methodology for investigating cognitive and physiological responses in pilot operations, mainly investigating cadet pilots’ vital parameters through diverse analytical methods and an exploration of scenario-specific demands.

Improve anti-glare ability of helicopters based on the anti-reflective structure of bionic moth eyes

This thesis focuses on the issue of glare during helicopter night navigation, which is caused by the high reflectivity of cockpit instruments, displays, and windshield surfaces. This can result in pilot eye fatigue and pose a serious threat to flight safety. To address this problem, a bionic moth eye antireflection structure is designed and prepared on the windshield glass surface using a combination of self-assembly and reactive ion beam technology. The aim is to reduce the surface reflectivity of the windshield glass and prevent glare. The anti-reflective structure comprises of conical structures with a size cycle of 15 nm and a structure height of 2000 nm. The surface of both sides is microstructured, resulting in a reduction of surface reflectivity from 8% to 0.5% at the wavelength of 300 nm to 800 nm. The passing rate is increased from 92% to 99.5%, and the applicable angle is greater than 50°). The anti-glare ability is improved by about 16 times. This thesis proposes a solution to the problem of glare during helicopter night navigation by designing and implementing a bionic moth eye antireflection structure on the windshield glass surface using self-assembly and reactive ion beam technology. The results show a significant reduction in surface reflectivity and improved anti-glare ability, which can contribute to enhancing flight safety.

Review of the Air Force Academy No.1 (49)/2024 49 FROM CLEAR SKIES TO ALL - WEATHER: THE EVOLUTION OF THE U.S. ARMY'S OPERATIONAL CAPABILITIES

Nowadays, within the Air Force, pilots train for instrumental flying in adverse weather conditions. The instrument flight program developed by the US military over 30 years ago, from the end of World War I to the late 1940s, is still in use today in many pilot training programs around the world. During the development of this program, the military was at the forefront of technological development.

Simulation of spin-echo SANS (SESANS) using McStas on monochromatic and time of flight instruments

We conduct simulations of Spin Echo Small Angle Neutron Scattering (SESANS) by employing Monte Carlo methods to a setup using four magnetic Wollaston prisms. Our primary focus involves the validation of these models, encompassing monochromatic scenarios across various neutron wavelengths to ascertain the reliability of the simulations. Subsequently, we extend this validation to encompass simulations in time-of-flight mode. Our model consistently and precisely predicts the scattering patterns emanating from dilute spheres in both monochromatic and time-of-flight modes. Notably, it also accurately reproduces the intricate encoding associated with scattering occurring between the third and fourth magnetic Wollaston prism, which provides us with another approach to increase the solid angle coverage of a SESANS instrument. This validation process conclusively demonstrates the efficacy of our simulation methods. Importantly, it paves the way for simulating more intricate and realistic instrumental configurations, broadening the horizons for future research endeavours.

Additional Clearance over Obstacles to Determine Minimum Flight Altitude in Mountainous Terrain

The International Civil Aviation Organization (ICAO) specifies that in the design phase of instrument flight procedures, an additional clearance may be added to an obstacle when flights are over mountainous terrain. This clearance increase can be up to 100 per cent of the minimum obstacle clearance (MOC). Airspace and instrument flight procedure designers usually face the problem of determining what value should be applied, since setting the maximum value of 100% often implies operational penalties, but there are no standardized criteria to determine lower values. The ICAO PANS-OPS indicates that the additional clearance over obstacles in mountainous areas is caused by two effects, both related to orography and wind speed. The first effect is due to the altimeter indication error. The second one is related to the loss of altitude when an aircraft is exposed to turbulence produced by mountain waves. This paper presents a methodology for determining the additional clearance to be applied over obstacles when, in the flight procedure design phase, the overflight of mountainous terrain is expected. Through this methodology, results have been achieved for the proposal of an appropriate additional clearance. The development of graphs and tables allows us to identify which additional value should be considered in each case.