IMPLEMENTATION OF TRANSONIC AREA RULE AND SWEPT BACK DELTA WING DESIGN ON AN AIRCRAFT.

The transonic area rule was first implemented in the 1950s. It is an important concept related to the drag on an aircraft or other body in transonic and supersonic flight which states that two airplanes with the same longitudinal cross-sectional area distribution have the same wave drag, independent of how the area is distributed laterally. A swept back delta wing increases the critical Mach number of the wing and performs well at low speeds, as a result of unique swirling vortices that form on the upper surface of the wing. BOOM Supersonic plans to bring back Supersonic Commercial aircrafts by implementing these modifications in the famous Concorde. In this paper two aircraft designs inspired by Concorde and BOOM Overture are compared using ANSYS Fluent. These were designed in CATIA with changes in fuselage dimensions, wing configuration and engine configuration. The lift to drag ratio of both the designs are calculated and compared. Pressure contours, velocity vectors, vector pathlines, turbulence pathlines and pressure pathlines are also compared. The results show that the design with the implementation of transonic area rule and swept back delta wing has a better Lift to Drag ratio when compared to the design with a wide fuselage and a delta wing design.

Sensor fault detection and reconstruction system for commercial aircrafts

The aim morphing of this study is to detect and reconstruct a fault in angle-of-attack sensor and pitot probes that are components in commercial aircrafts, without false alarm and no need for additional measurements. Real flight data collected from a local airline was used to design the relevant system. Correlation analysis was performed to select the data related to the angle-of-attack and airspeed. Fault detection and reconstruction were carried out by using Adaptive Neural Fuzzy Inference System (ANFIS) and Artificial Neural Networks (ANN), which are machine-learning methods. No false alarm was detected when the fault test following the fault modeling was carried out at 0–1 s range by filtering the residual signal. When the fault was detected, fault reconstruction process was initiated so that system output could be achieved according to estimated sensor data. Instead of using the methods based on hardware redundancy, we designed a new system within the scope of this study.

PIV measurement of a jet from a gasper in an aircraft cabin mockup

The air conditioning system of most commercial aircrafts consists of a main system, which operates on the principle of mix ventilation, and a personalized system called gasper. Field studies show that passengers prefer to keep gasper parcially open or redirect it away from the head due to the discomfort. Therefore, there is a demand to characterize the flow of this device for future improvements. In this way, the present work aims to experimentally study the gasper jet inside a real cabin mockup using PIV. The results indicate that passengers are subjected to a high speed jet and the air in their breathing zone is mostly supplied by the mixed ventilation system due to the large entrainment ratio.

Evaluation method of military aircraft noise using AI analysis of aircraft images

In recent aircraft noise survey in Japan, noise data is associated with each aircraft by flight log or by radio information including transponder signals. Especially, above Tokyo metropolitan area, flight tracks are tangled extremely each other, therefore assessments from various perspectives such as departure / arrival airport, used runway, aircraft model, and operator have been demanded for determining noise policies. However, for military aircrafts, it is not easy to identify their information with the same way as commercial aircrafts, because their flight logs are not disclosed and many of them do not emit transponder signals like commercial aircrafts. Therefore, manned 24 hours survey around air bases have been necessary to obtain flight information of military aircrafts. In this paper, we propose an AI-based analysis using captured aircraft images for obtaining actual flight data of military aircrafts. In the past trials, we could determine the takeoff/landing time and the aircraft model by the above method. Associating these information and noise data measured at monitoring stations, details of noise characteristics around the air base can be clearly grasped. Advanced analysis of the causes of noise impact will lead effective and concrete countermeasures.

Civil Aviation Occurrences in Slovakia and their Evaluation Using Statistical Methods

The nature of a civil aviation occurrence may be defined in three different categories while considering its severity. General categories include civil aviation accidents, serious incidents and incidents. The present article analyses the civil aviation occurrences in Slovakia which happened in the period from 2000 to 2019. In this period, there was a significant increase in the number of civil aviation occurrences, and incidents, in particular, represented the highest percentage. A Pareto analysis was applied to identify the key incident categories (wildlife strike, technical failures of the aviation technology and unauthorised penetration of airspace). A multiple regression analysis and the Poisson regression were used to create two models of correlations between the number of civil aviation occurrences and the selected input variables. Both models are statistically significant, and, based on the AIC (Akaike Information Criterion), the Poisson regression model appeared to be of higher quality. The model showed, for example, that an increase in variables (the number of commercial aircrafts aged over 14 years and the number of total aircraft movements) resulted in a slight increase in the expected number of civil aviation occurrences.

Results of a Feasibility Study of a Prognostic System for Electro-Hydraulic Flight Control Actuators

Electro-Hydraulic Servo-Actuators (EHSA) are currently the most used actuation technology for primary flight control systems of civil and military aircrafts. Although some alternatives have emerged in the last decade, such as electromechanical or electro-hydrostatic solutions, electrohydraulic systems are still considered the most effective technology in flight-critical application of new commercial aircrafts. Moreover, the vast majority of aircraft currently in service are equipped with this technology. Considering the number of actuators typically employed in a primary flight control system and the expected service life of a commercial aircraft, the development of an effective PHM system could provide significant benefits to fleet operators and aircraft maintenance. This paper presents the results of a feasibility study of such a system for electro-hydraulic actuators used in fly-by-wire primary flight control systems, considering the actuator of a wide body commercial aircraft as use case. Aim of the research is the implementation of a PHM system without the addition of dedicated sensors, solution which would allow for the application of the proposed prognostic solution on both new and existing platforms. This paper describes the methodology and the results of the feasibility study through simulation and experimental activities, which shows how the novel PHM technologies proposed for a PHM system for the EHSAs of primary flight control actuators can allow the migration from scheduled to condition-based maintenance.

Environmental impact of pollutants from commercial aircrafts at Hasan Polatkan airport

Purpose This paper aims to investigate the environmental impact of various pollutant emissions including carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxide (NOx) and hydrocarbon (HC) from aircraft exhaust gases during the landing and take-off (LTO) cycles at Eskisehir Hasan Polatkan Airport, Turkey, between 2017 and 2018. Design/methodology/approach The methodology approach used to calculate the emissions from aircrafts is based on the ICAO databank and the actual data records taken from Presidency of The Republic of Turkey Directorate of Communications (DoC). Findings The maximum amount of total fuel burnt during the two years is 80.898 and 70.168 tons in 2017 and 2018, respectively, while the average fuel burnt per year from 2017 to 2018 is approximately 369.773 tons. The highest CO, CO2, NOx and HC emissions are found to be 248.3 kg in 2017, 261.380 tons, 1.708 tons and 22.15 kg, during the 2018 year, respectively. Average CO, HC, NOx and CO2 emissions amount per year are observed to be 1.392 tons, 135 kg, 6.909 tons and 1,143 tons, respectively. Considering the average of total emission amount as an environmental factor, as expected, CO2 emissions contributed the most to the total emissions while HC emissions contributed the least to the total emissions from the airport. Practical implications The study presents the approach in determining the amounts of emissions released into the interannual atmosphere and it explicitly provides researchers and policymakers how to follow emissions from commercial aircraft activities at different airports. Originality/value The value of the study lies in the transparent computation of the amounts of pollutants by providing the data directly from the first hand-DoC.

Elliptical Tabs as a Mixing Enrichment Tool for Jet Nozzles

Mixing efficiency helps to thrust gain and jet noise reduction. Aerospace and aviation research communities around the world are constantly demanding cleaner, quieter and more efficient commercial aircrafts. Though there are many sources of noise during flight, one such is deficient mixing of air at the rear of the nozzle, uneven expansion of nozzle and corresponding engine noise is quite dominant. The mixing proficiency is achieved by mixing of cold air at the surroundings with the hot air that exits through the nozzle. To reduce the engine noise, elliptical tabs are employed at the exit of convergent nozzle. These are passive noise controllers which create vortices to the existing flow and entrains cold mass from the surroundings in order to reduce noise level. This paper is concerned with the various shapes and sizes of tabs to test the mixing efficiency at different Mach numbers. Further, it is evaluated by both qualitative and quantitative analysis of shadowgraph system and the pressure identifying method using some of the propitious pressure scanner.

On COVID-19-safety ranking of seats in intercontinental commercial aircrafts: A preliminary multiphysics computational perspective

The evolution of coronavirus disease (COVID-19) into a pandemic has severely hampered the usage of public transit systems. In a post-COVID-19 world, we may see an increased reliance on autonomous cars and personal rapid transit (PRT) systems, with inherent physical distancing, over buses, trains, and aircraft for intracity, intercity, and interstate travel. However, air travel would continue to be the dominant mode of intercontinental transportation for humans. In this study, we perform a comprehensive computational analysis of typical intercontinental aircraft ventilation systems to determine the seat where environmental factors are most conducive to human comfort with regards to air quality, protection from orally or nasally released pollutants such as CO2 and coronavirus, and thermal comfort levels. Air velocity, temperature, and air pollutant concentration emitted from the nose/mouth of fellow travelers are considered for both Boeing and Airbus planes. In each plane, first class, business class, and economy class sections were analyzed. We present conclusions as to which is the optimum seat in each section of each plane and provide the data of the environmental conditions to support our inferences. The findings may be used by the general public to decide which seat to occupy for their next intercontinental flight. Alternatively, the commercial airliners can use such a model to plan the occupancy of the aircraft on long-duration intercontinental flights (viz., Airbus A380 and Boeing B747).