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1 – 10 of 27Susan V. White and Karen Hallows
This case was researched using publicly available sources, including Mercury Systems financial filings and press releases, news stories about the seasoned equity offering…
Abstract
Research methodology
This case was researched using publicly available sources, including Mercury Systems financial filings and press releases, news stories about the seasoned equity offering, financial information from Bloomberg and industry information from IBISWorld Industry Reports and articles related to seasoned/secondary equity offerings, intangible asset valuation and the use of revolving lines of credit. Quotes are taken from Mercury financial reports and press releases and express the (optimistic) opinions of company executives.
Case overview/synopsis
Mercury Systems, a technology company in the aerospace and defense industry, announced a six million share seasoned stock offering in June 2019. This resulted in a 6% stock price decrease. A stock price decrease is a typical event when a firm announces the issuance of new common shares, but with Mercury Systems, there were concerns about how much money the firm needed to fund its strategy of growth through acquisitions. If internally generated funds were not sufficient, should the firm issue debt or have another seasoned equity issue? Students will look at the objectives and success of the most recent seasoned equity issue, determine future funds needs and how the firm should finance these needs.
Complexity academic level
This case is appropriate for undergraduate and graduate students in corporate finance electives. Typically, topics such as seasoned equity offerings are not covered in introductory courses, so this is recommended for finance electives. Even in advanced finance courses, sometimes there is insufficient time to cover seasoned equity offerings.
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Hamdi Ercan, Cüneyt Öztürk and Mustafa Akın
This paper aims to assess the impact of electrifying the environmental control system (ECS) and ice protection system (IPS), the primary pneumatic system consumers in a…
Abstract
Purpose
This paper aims to assess the impact of electrifying the environmental control system (ECS) and ice protection system (IPS), the primary pneumatic system consumers in a conventional commercial transport aircraft, on aircraft weight, range, and fuel consumption.
Design/methodology/approach
The case study was carried out on Airbus A321-200 aircraft. Design, modelling and analysis processes were carried out on Pacelab SysArc software. Conventional and electrical ECS and IPS architectures were modelled and analysed considering different temperature profiles.
Findings
The simulation results have shown that the aircraft model with ±270 VDC ECS and IPS architecture is lighter, has a more extended range and has less relative fuel consumption. In addition, the simulation results showed that the maximum range and relative fuel economy of all three aircraft models increased slightly as the temperature increased.
Practical implications
Considering the findings in this paper, it is seen that the electrification of the conventional pneumatic system in aircraft has positive contributions in terms of weight, power consumption and fuel consumption.
Social implications
The positive contributions in terms of weight, power consumption and fuel consumption in aircraft will be direct environmental and economic contributions.
Originality/value
Apart from the conventional ECS and IPS of the aircraft, two electrical architectures, 230 VAC and ±270 VDC, were modelled and analysed. To see the effects of the three models created in different temperature profiles, analyses were done for cold day, ISA standard day and hot day temperature profiles.
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Erol Can and Ugur Kilic
Static inverters are very important for the emergency energy distribution system of aircraft and similar machines. At the same time, the electrical energy produced at high…
Abstract
Purpose
Static inverters are very important for the emergency energy distribution system of aircraft and similar machines. At the same time, the electrical energy produced at high frequency for electrical devices is used to reduce the weight of the cables in the aircraft and spacecraft because of the skin effect. In the high-frequency system, a thinner cable cross-section is used, and a great weight reduction occurs in the aircraft. So, fuel economy, less and late wear of the materials (landing gear, etc.) can be obtained with decreasing weight. This paper aims to present the development of a functional multilevel inverter (FMLI) with fractional sinus pulse width modulation (FSPWM) and a reduced number of switches to provide high-frequency and quality electrical energy conversion.
Design/methodology/approach
After the production of FSPWM for FMLI with a reduced component, which, to the best of the authors’ knowledge, is presented for the first time in this study, is explained step by step, and eight operating states are given according to different FSPWMs operating the circuit. The designed inverter and modulation technique are compared by testing the conventional modular multilevel inverter on different loads.
Findings
According to application results, it is seen that there is a 50% reduction in cross-section from 100 Hz to 400 Hz with the skin effect. At 1000 Hz, there is a 90% cross-section reduction. The decrease can be in cable weights that may occur in aircraft from 10 kg to 100 kg according to different frequencies. It causes less harmonic distortion than conventional converters. This supports the safer operation of the system. Compared to the traditional system, the proposed system provides more amplitude in converting the source to alternating voltage and increases the efficiency.
Practical implications
FSPWM is developed for multilevel inverters with reduced components at the high frequency and cascaded switching studies in the power electronics of aircraft.
Social implications
Although the proposed system has less current and power loss as mentioned in the previous sections, it contains fewer power elements than conventional inverters that are equivalent for different hardware levels. This not only reduces the cost of the system but also provides ease of maintenance. To reduce the cable load in aircraft and create more efficient working conditions, 400 Hz alternative voltage is used. The proposed system causes less losses and lower harmonic distortions than traditional systems. This will reduce possible malfunctions and contribute to aircraft reliability for passengers and cargo. As technology develops, it is revealed that the proposed inverter system will be more efficient than traditional inverters when devices operating at frequencies higher than 400 Hz are used. With the proposed inverter, safer operation will be ensured, while there will be less energy loss, less fuel consumption and less carbon emissions to the environment.
Originality/value
The proposed inverter structure shows that it can provide energy transmission for electrical devices in space and aircraft by using the skin effect. It also contains less power elements than the traditional inverters, which are equivalent for different levels of hardware.
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Albert Zajdel, Michal Welcer and Cezary Jerzy Szczepanski
This paper aims to present assessment of models and simulation results used in the development process of flight stabilisation system that uses trim tabs for PZL-130 Orlik…
Abstract
Purpose
This paper aims to present assessment of models and simulation results used in the development process of flight stabilisation system that uses trim tabs for PZL-130 Orlik turboprop military trainer aircraft. Flight test of the system allowed to compare software and hardware simulation results with real flight recordings.
Design/methodology/approach
Proposed flight stabilisation system was developed using modern techniques of model-based design, automatic code generation, software and hardware in the loop testing. The project reached flight testing stage which allowed to gather data to verify models and simulation results and asses their quality.
Findings
Results of the comparison showed that the trim tab actuator model used in simulation can be improved by adding play. This reduced the difference between simulation and real flight system output – actuator angle. The influence of airloads on the flying actuator angle compared to hardware in the loop simulation in lab is less than ± 0.6°.
Originality/value
Proposed flight stabilisation system that uses trim tabs has several benefits over classic automatic flight system in terms of weight, energy consumption and structure simplicity and does not need aircraft primary control modification. It was developed using modern techniques of model-based design, automatic code generation and hardware in the loop simulations.
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Serap Kiriş and Muharrem Karaaslan
The purpose of this study is to design a radio altimeter antenna whose production process is facilitated and can work with multiple-input multiple-output (MIMO) properties to…
Abstract
Purpose
The purpose of this study is to design a radio altimeter antenna whose production process is facilitated and can work with multiple-input multiple-output (MIMO) properties to provide space gain on the aircraft.
Design/methodology/approach
To create an easy-to-produce MIMO, a two-storied structure consisting of a reflector and a top antenna was designed. The dimensions of the reflector were prevented to get smaller to supply easy production. The unit cell nearly with the same dimensions of a lower frequency was protected through the original cell design. The co-planar structure with the use of a via connection was modified and a structure was achieved with no need to via for easy production, too. Finally, the antennas were placed side by side and the distance between them was optimized to achieve a MIMO operation.
Findings
As a result, an easy-to-produce, compact and successful radio altimeter antenna was obtained with high antenna parameters such as 10.14 dBi gain and 10.55 dBi directivity, and the conical pattern along with proper MIMO features, through original reflector surface and top antenna system.
Originality/value
Since radio altimeter antennas require high radiation properties, the microstrip antenna structure is generally used in literature. This paper contributes by presenting the radio altimeter application with antenna-reflective structure participation. The technical solutions were developed during the design, focusing on an easy manufacturing process for both the reflective surface and the upper antenna. Also, the combination of International Telecommunication Union’s recommended features that require high antenna properties was achieved, which is challenging to reach. In addition, by operating the antenna as a successful MIMO, two goals of easy production and space gain on aircraft have been attained at the same time.
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The basis of safe flight is the management of risks. This paper aims to present a new process-based risk assessment model, with an approach to calculate the risk score.
Abstract
Purpose
The basis of safe flight is the management of risks. This paper aims to present a new process-based risk assessment model, with an approach to calculate the risk score.
Design/methodology/approach
Since thousands of minor changes occur within ground operations, it is difficult to calculate how much risk these variations will pose. This paper proposes a risk assessment model fed from analysis of ground operation processes using functional resonance analysis method (FRAM) and fuzzy logic.
Findings
FRAM is used to detect variations in ground operation. Using the FRAM analysis, it has been revealed how much risk the process steps described in the procedures involve. The risk score was calculated by combining the probability value obtained from the airline’s database and the severity assessment of the expert group in fuzzy logic. The risk level can be monitored dynamically with the transfer of events in the airline’s database to the process-based risk assessment model.
Originality/value
FRAM analysis, which is used to detect function variations before undesirable risk occurs, has brought a proactive approach to risk assessment. The process-based risk assessment model allows the creation of new safety parameter indicators to be followed to reduce the risk level of the function with a high-risk level. The proposed approach can be used for other operational areas in aviation as well.
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Preeti Godabole and Girish Bhole
The main purpose of the paper is timing analysis of mixed critical applications on the multicore system to identify an efficient task scheduling mechanism to achieve three main…
Abstract
Purpose
The main purpose of the paper is timing analysis of mixed critical applications on the multicore system to identify an efficient task scheduling mechanism to achieve three main objectives improving schedulability, achieving reliability and minimizing the number of cores used. The rise in transient faults in embedded systems due to the use of low-cost processors has led to the use of fault-tolerant scheduling and mapping techniques.
Design/methodology/approach
The paper opted for a simulation-based study. The simulation of mixed critical applications, like air traffic control systems and synthetic workloads, is carried out using a litmus-real time testbed on an Ubuntu machine. The heuristic algorithms for task allocation based on utilization factors and task criticalities are proposed for partitioned approaches with multiple objectives.
Findings
Both partitioned earliest deadline first (EDF) with the utilization-based heuristic and EDF-virtual deadline (VD) with a criticality-based heuristic for allocation works well, as it schedules the air traffic system with a 98% success ratio (SR) using only three processor cores with transient faults being handled by the active backup of the tasks. With synthetic task loads, the proposed criticality-based heuristic works well with EDF-VD, as the SR is 94%. The validation of the proposed heuristic is done with a global and partitioned approach of scheduling, considering active backups to make the system reliable. There is an improvement in SR by 11% as compared to the global approach and a 17% improvement in comparison with the partitioned fixed-priority approach with only three processor cores being used.
Research limitations/implications
The simulations of mixed critical tasks are carried out on a real-time kernel based on Linux and are generalizable in Linux-based environments.
Practical implications
The rise in transient faults in embedded systems due to the use of low-cost processors has led to the use of fault-tolerant scheduling and mapping techniques.
Originality/value
This paper fulfills an identified need to have multi-objective task scheduling in a mixed critical system. The timing analysis helps to identify performance risks and assess alternative architectures used to achieve reliability in terms of transient faults.
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The imposition of Western sanctions on Russia’s commercial aviation sector in response to the full-scale invasion of Ukraine led some to predict the collapse of the industry…
Details
DOI: 10.1108/OXAN-DB284403
ISSN: 2633-304X
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Geographic
Topical
Satyanandini Arjunan, Minu Zachariah and Prathima K. Bhat
Alpha Design Technologies Private Limited (ADTL) was started in 2004 by Colonel H.S. Shankar after his retirement from services in the Indian Army and Bharat Electronics Limited…
Abstract
Learning outcomes
Alpha Design Technologies Private Limited (ADTL) was started in 2004 by Colonel H.S. Shankar after his retirement from services in the Indian Army and Bharat Electronics Limited (BEL). Aggressively growing the company from US$0.04m in 2004 to US$100m in 2022, he proved that age was not a barrier to success in entrepreneurship. His aspirations were to gain a greater presence in foreign markets through higher exports. After reading this case study, the students will be able to understand how the defence sector evolved in India and the role of private-sector enterprises; recognise the risks and opportunities in the changing dynamics of defence sector in India; believe that the ideas and capabilities of an entrepreneur increase with relevant previous experiences; appreciate the ambition and managerial capabilities of an entrepreneur even at the age of 60; apply Ajzen’s theory of planned behaviour on the entrepreneurial journey of Shankar and formulate strategies for growth.
Case overview/synopsis
Started in the year 2004, ADTL specialises in manufacturing defence-related products. ADTL was cofounded by Shankar, at the age of 60. His experience of working with the Indian Army and BEL in various capacities gave him the proficiency to start a venture on his own after his retirement. The ecosystem in India was favourable for ADTL as the Government opened up the defence sector for private players. Nevertheless, age was not a barrier for this senior citizen to tap the opportunity and work aggressively to grow his venture from US$0.04m in 2004 to US$100m in 2022. By 2023, ADTL had an employee strength of 1,200 including 650 engineers, and they emerged as a market leader in Software Defined Radio space. They manufactured around 200 different products for defence and space. ADTL exported 60% of the defence products to countries such as Israel, the USA and Germany. Moving forward, the dream for Shankar was to make a mark in the defence geography of the world through ADTL, by improving its export volumes and also through strategic alliances.
Complexity academic level
This case study can be taught to Master of Business Administration/postgraduate degree in management students as a part of the introductory course on entrepreneurship and strategy. This case study can be used specifically to make the students understand the role of private sector in the manufacturing of defence products after the liberalisation policy of the Government of India. The intention was not only to protect the nation from the threat posed by neighbouring countries but also to promote exports of defence products to other countries to improve foreign exchange earnings.
Supplementary materials
Teaching notes are available for educators only.
Subject code
CSS 3: Entrepreneurship.
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José Nogueira da Mata Filho, Antonio Celio Pereira de Mesquita, Fernando Teixeira Mendes Abrahão and Guilherme C. Rocha
This paper aims to explore the optimization process involved in the aircraft maintenance allocation and packing problem. The aircraft industry misses a part of the optimization…
Abstract
Purpose
This paper aims to explore the optimization process involved in the aircraft maintenance allocation and packing problem. The aircraft industry misses a part of the optimization potential while developing maintenance plans. This research provides the modeling foundation for the missing part considering the failure behavior of components, costs involved with all maintenance tasks and opportunity costs.
Design/methodology/approach
The study models the cost-effectiveness of support against the availability to come up with an optimization problem. The mathematical problem was solved with an exact algorithm. Experiments were performed with real field and synthetically generated data, to validate the correctness of the model and its potential to provide more accurate and better engineered maintenance plans.
Findings
The solution procedure provided excellent results by enhancing the overall arrangement of the tasks, resulting in higher availability rates and a substantial decrease in total maintenance costs. In terms of situational awareness, it provides the user with the flexibility to better manage resource constraints while still achieving optimal results.
Originality/value
This is an innovative research providing a state-of-the-art mathematical model and an algorithm for efficiently solving a task allocation and packing problem by incorporating components’ due flight time, failure probability, task relationships, smart allocation of common preparation tasks, operational profile and resource limitations.
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