Search results

This paper aims to investigate the effects of descent time spent with flaps extended on fuel burn (FB) and specific range for five different flight path angles (FPAs) ranging between 2.0° and 4.0° for a commercial aircraft.

A large data set of actual flight data (n = 475) of the same type of a frequently used commercial aircraft were investigated by using statistical methods.

The result of the comparison of the highest and the lowest FBs of flight profiles for each FPAs present that the fuel saving was achieved by keeping at as a high airspeed as possible and deploying flaps as late as possible, which is in line with the objective of delayed deceleration approaches. From analyzing the flight profiles, it was proven that delaying deceleration and also descending without flaps or with flap over a shorter time resulted in less FB of 101.1, 70.9 and 94.9 kg for FPA 2.5°, FPA 3.0° and FPA 3.5°, respectively.

This study differs from prior studies because it focused on the effects of the different vertical profiles on FB. Also, the use of real flight data recorder data in the analysis presents the originality of this study.

Metroplex is a system of two or more airports, in physical proximity, with highly interdependent arrival and departure operations. The purpose of this study is the construction of an efficient and effective air route model based on the point merge system (PMS) to reduce aircraft fuel consumption and CO₂ emissions for three metroplex airports in Istanbul terminal control area (TMA).

A PMS arrival route model is constructed for metroplex airports. In the proposed model, two situations are taken into consideration: for delay which can be defined as flying on sequencing legs (PMS_del) and for no delay (PMS_{no del}). An empirical model is developed using a data set including the flight data records of ten actual B737-800 domestic flights. With this empirical model, both the baseline and the PMS models (PMS_del and PMS_{no del}) are compared in terms of fuel consumption, CO₂ emissions and flight distance and time as a theoretical computation.

In the proposed PMS_{no del} arrival route model, according to different entry points for Istanbul Ataturk International Airport (LTBA), the analyses show an average reduction of 26 per cent in flight time, 24.5 per cent in flight distance, 17 per cent in fuel burned and CO₂ emissions; in addition, for Sabiha Gökcen International Airport (LTFJ) there are 34, 23 and 32 per cent average savings for flight time, flight distance and fuel burned together with CO₂ emissions obtained, respectively. Even if the PMS_del model, for LTFJ except only one entry point, for LTBA except two entry points, better results are obtained than baseline.

The point merge model for metroplex airports in this paper can be applied by airspace designers and Air Navigation Service Providers to perform efficient and effective arrival routes.

In this study, a point merge model is constructed for metroplex airports. Quantitative results, using an empirical model, are achieved in terms of fuel consumption, CO₂ emissions and flight distance and time at metroplex airports.

The purpose of this paper is to create a new fuel flow rate model using cuckoo search algorithm (CSA) for the descending stage of the flight.

Using the actual flight data record data of the B737-800 aircraft, a new fuel flow rate model has been developed for this aircraft type. The created model is to predict the fuel flow rate with high accuracy depending on the altitude and true airspeed. In addition, the CSA fuel flow rate model was used to calculate the fuel consumption for the point merge system, which is used for combining the initial approach to the final approach at Istanbul Airport, the largest airport of Turkey.

As a result of the analysis, the correlation coefficient value is found as 0.996858 for Flight 1, 0.998548 for Flight 2, 0.995363 and 0.997351 for Flight 3 and Flight 4, respectively. The values that are so close to 1 indicate that the model predicts the real fuel flow rate data with high accuracy.

This model is considered to be useful in air traffic management decision support systems, aircraft performance models, models used for trajectory prediction and strategies used by the aviation community to reduce fuel consumption and related emissions.

The importance of this study lies in the fact that to the best of the authors’ knowledge, it is the first fuel flow rate model developed using CSA for the descent stage in the existing literature; the data set used is real values.

The study aims to design a new route model for unmanned aerial vehicles (UAVs) to integrate them into non-segregated airspace.

The proposed route model was assessed and validated through real-time simulations.

The comparison results of baseline and proposed route model show that a reduction of 38% and 41% in the total flight time and total flight distance were obtained in favour of the proposed model, respectively.

The proposed route model can be applied by airspace designers and UAV users to perform safe and efficient landing in non-segregated airspace.

In this study, a new proposed route model is constructed for UAVs. Quantitative results, using a real-time simulation method, are achieved in terms of flight distance and flight time.

Unmanned aerial vehicles (UAVs) are more affected by adverse wind conditions in especially landing. Therefore, they need to change the runway in use. In case of this change, to eliminate the uncertain maneuvers, there is a need for a special prescribed track. The purpose of this study is the construction of a prescribed track at a single runway to provide a facility to change the runway in use.

Two forms of prescribed tracks, as standard and alternate, were constructed for UAVs by taking into consideration the key parameters to design flight procedures. Both tracks were assessed in a real-time simulation method. Moreover, unmanned vehicle simulation was used for a validation process.

According to the real-time simulation results, 8.14 NM and 6.64 NM of flight distance and 5.43 min and 4.43 min of flight time for the standard and alternate prescribed tracks were found, respectively. The obtained results were in favor of the alternate prescribed track. Furthermore, the prescribed track was assessed and validated in both air traffic control and UAV simulations. The feedback of pilots and controllers was very positive for a prescribed track, as it provided them with foresight and time to take care in any situations.

The prescribed track in this paper may be applied by airspace designers and UAV users to perform safe and efficient landing in adverse wind conditions.

In this study, a prescribed track was constructed for UAVs. Quantitative results were achieved using a real-time simulation method in terms of flight distance and flight time. Additionally, validation of the prescribed track was achieved by unmanned air vehicle simulation.

The purpose of this paper is to design a new standard instrument arrival called the point merge system (PMS) for converging runways. The PMS enables controllers to handle traffic with no heading instruction, as well as aiming to reduce a controller's frequency occupancy time.

The point merge model was designed for converging runways. Istanbul International Ataturk Airport, which has converging runways, was chosen as an application area for this model. The same 50 traffic arrivals per hour were used both for point merge and vectoring. Implementation was compared using a real time simulation.

The simulation results show that the total average number of instructions is about 33 per cent less and the frequency occupancy is about 37 per cent less for point merge than for vectoring. In addition, in terms of trajectory dispersion, in point merge, traffic is within a narrower triangular area, while in vectoring large traffic dispersion occurs.

The point merge model for converging runways proposed in this paper can be applied by airspace designers and air navigation service providers to perform efficient standard instrument arrival routes.

The PMS has been developed for single and parallel runways; however, in this study, the point merge model is designed for converging runways at Istanbul International Ataturk Airport.

This case study was prepared through secondary research. The secondary data was collected in electronic format from the internet. Archived data from the company sources as well as other resources available online was used. Financial reporting about Pfizer Inc. (Pfizer) was done using data from the company’s annual reports.

This case discusses US-based pharmaceutical giant Pfizer’s successful rollout of the Covid-19 vaccine under the leadership of its Chief Executive Officer Albert Bourla (Bourla). In March 2020, when the World Health Organization declared Covid-19 a pandemic, leaders of pharmaceutical giants worldwide were in no way prepared to find a cure for the disease caused by the novel coronavirus. On the other hand, Bourla stood up like a true leader and sought to do something to address the problem. Bourla’s huge gamble paid off. In December 2020, the Food and Drug Administration approved the Covid-19 vaccine developed by Pfizer. Pfizer was ready with 50 million vaccine doses for global distribution.

This case is intended for use in MBA/MS level programs as part of the curriculum on Effective Leadership and Decision-making, and Crisis Management.

Continuous descent approach (CDA) is a method, which allows the aircraft flying its individual optimal vertical profile down to runway threshold with engines operating at low‐thrust power. The main objective of this paper is to provide less‐fuel consumption, less noise and less emission with using CDA procedures instead of conventional procedures.

Conventional and CDA procedures were modelled in the Istanbul terminal area (TMA), which has five entry points. The real speed and the real altitude limitations were maintained on these entry points. System for Assessing Aviation's Global Emissions research results were also used to determine the emission savings.

With CDA procedures, more than 40 kg fuel and 2 min time savings per flight are obtained; furthermore, regarding CO₂ and H₂O, significant emission savings are also noted.

Some of the benefits of CDA procedures are reported for Istanbul TMA by using true flight data.

The purpose of the research is to analyze the factors that determine the intention of small- and medium-sized enterprises (SMEs) to adopt the Metaverse. For this purpose, the analysis of the effort expectancy and performance expectancy of the constructs in relation to business satisfaction is proposed.

The analysis was performed on a sample of 182 Spanish SMEs in the technology sector, using a PLS-SEM approach for development. For the confirmation of the model and its results, an analysis with PLSpredict was performed, obtaining a high predictive capacity of the model.

After the analysis of the model proposed in this research, it is recorded that the valuation of the effort to be made and the possible performance expected by the companies does not directly determine the intention to use immersive technology in their strategic behavior. Instead, the results obtained indicate that business satisfaction will involve obtaining information, reducing uncertainty and analyzing the competition necessary for approaching this new virtual environment.

The study represents one of the first approaches to the intention of business behavior in the development of performance strategies within Metaverse systems. So far, the literature has approached immersive systems from perspectives close to consumer behavior, but the study of strategic business behavior has been left aside due to the high degree of experimentalism of this field of study and its scientific approach. The present study aims to contribute to the knowledge of the factors involved in the intention to use the Metaverse by SMEs interested in this field.

This study aims to explore ways of developing, implementing and validating a new framework and criteria for self-evaluation of programme curricula, with specific reference to the quality assurance certification process in a particular case.

The framework is developed using a case study research methodology and implemented based on criteria extraction through the triangulation of indicators achieved from internal goals and external directives.

The findings reveal that this is an improvement-led framework that can be adapted to other contexts during the quality assurance processes to facilitate periodical programme evaluations with a focus on the curriculum.

The proposed practical tool is developed for the programme evaluation process with a curricular focus during the quality assurance certification process of an interior architectural programme while enlightening the processes for the periodical self-evaluations of other institutions. The framework depends on both institution-specific internal and external directives and fulfilling curriculum-related criteria of the European Standards and Guidelines for Quality Assurance.

Within quality assurance processes, despite external quality assurance mechanisms, there is a shortage of self-evaluation tools for internal quality assurance procedures, which allow the dissociation of programme-specific qualities. The proposed framework is developed as an example of a self-tailored internal quality assurance tool and process for educational institutions to reveal their unique qualities.