Medium Range Aircraft Fuel Policy in the Light of Available Software, and Knowledge in the Industry

The rational use of fuel in aviation industry together with the improved operational safety level and productivity are common and permanent goal that all airlines in the world strive to achieve. Different environmental influences and constraints affect each of them through multiple layers of activities. The constant awareness of them and mastering equipment airline exploits make reaching those goals more viable. Croatia Airlines is the sole Croatian scheduled air carrier. Being major consumer of fuel and having in mind international sense that air transportation has Croatia Air-lines has to obey worldwide applied criteria. Paper lists environmental influences together with airline characteristics that make fuel policy so important factor. It compiles theoretical foundation together with methods used in formulating fuel policy. Operational data and its use for deriving one of the indicators related to medium range aircraft fuel consumption are listed at the end

Different Automation Concepts in Civil Aircraft Cockpits of Today and Their Influence on Airline Flight Operations

Although there are different aircraft manufecturers and hence different practical solutions, there is one bottom line in automation. In aviation automation is only complement to humans. It is not present to challenge the pilot's role and responsibility. The use of new technologies and implementation of new functionality are dictated only by: significant safety benefits, obvious operational advantages, and clear response to the pilot's needs and operational factors influencing his functioning. The paper will discuss different approaches to automation related to flight operations in aviations. The paper intends to demonstrate how different manufacturers' approaches follows quite similar ideas in different automated system designs. The paper does not intend to give any final say when choosing one concept or the other. That is the matter of different circumstances requiring more justifying space and different criteria than the pure scientific one

The Example of Laptop Based Performance Data Generating and Optimisation in Contemporary Commercial Aircraft Operations

Airframe and engine combination gives equal potential to every operator with such a hardware combination. Operator's way of utilization makes its use to the maximum or less. Data related to aircraft performance is one of the basic elements in daily aircraft operations and optimal utiliza-tion of airframe and engine combination in real life environment. New technological solutions and systems affected performance data calculation. Today's laptop computer technology has already boarded the flight deck together with pilots. This paper is to present possible structure and proposed application of one of the system together with envisaged effects of its use in real life commercial aircraft operations. It will present the over-view of the system with considerations taken into account when designing and developing it; it's potentials and advantages compared to paper based performance data calculation and optimiza-tion: and the most important how it is understood as a tool in very demanding, unpredictable air-line operations of today

Automated Operations and Safety Data Collection and Usage in Contemporary Flight Operations Quality Audit Programs

Flight Operations Quality Audit (FOQA) programs are becoming more common to airlines of today. Flight data recording devices modified for repeated and daily data readouts have been dem-onstrating their unquestionable advantages in FOQA programmes. They demonstrate the interest of airlines, that use them, to transport people, cargo and mail in safe and efficient way. The paper will present general FOQA structure, historical developments in this field together with common obstacles when introducing FOQA to an airline. It also brings the latest data and understanding of benefits that FOQA has on airlines operation with potential applications of similar concepts to other means of transportation as well

Flight Operations and Engineering Documentation Managing and Distribution Supported by Intelligent Transport Systems

Aviation as a multitude of activities is meant to satisfy needs of its customers to overcome distance and time between any departure and arrival point in the world. Airlines and other aircraft operators (governments, armed forces, general aviation, and business aviation) differ in their structure depending on their size and services they provide. Some departments are to be found in larger airlines only. However, core departments, to every airline or aircraft operator, are flight operations department and engineering department. Sophistication and the size of these departments depend on the size of the system they are incorporated in. Business logistics of an airline consist of numerous distinctive activities and functions. These activities have to be planned and completed in synchronisation. The paper presents an overview to intelligent systems for the support to these activities with particular stress on flight operations and maintenance functions in a medium sized airline. Authors show how the approach to documentation management, as a part of logistics in the production of transportation service, has evolved since the early 1990s when aviation has started to recognise the value of digital technical data. In light of this, authors analyse conceptual framework adopted by today's aircraft manufacturers towards their logistics activities supported by Internet as a new means of transferring data. The advent of new sophisticated pilot-machine interfaces and aircraft systems tends to increase the volume of the documentation describing these tools drastically. The paper communicates how operational documentation has to change to move towards a more easy and modern media. Intelligent systems that prove aviation entering a period where the "written book" is going to be complemented if not largely supplemented by the "electronic book" are presented from the early beginnings of digital data application to the most recent achievements

Risk Assessment, Modelling And Proactive Safety Management System In Aviation: A Literature Review

Safety and Risk are in the focus of the constant research ranging from strictly technical and technological to organisational influence. The increase of system’s complexity and the shift of errors from purely mechanical to human and organisational has hampered the study and the prediction of accident probability. This paper reviews the literature for the Safety Management System (SMS) in aviation for their ability to account for the complex dynamics from which safety in these kinds of systems tends to emerge – or not. After this, it evaluates existing risk assessment modelling so as to assess the ‘status’ – or analytical strength – in this domain. The shortcomings of those models are presented to identify potential effective model’s elements in relation to assessed the body of literature and current complex socio-technological systems present in air transportation system and other High Risk Organisation

Relativistic Winds from Compact Gamma-ray Sources: I. Radiative Acceleration in the Klein-Nishina Regime

We consider the radiative acceleration to relativistic bulk velocities of a cold, optically thin plasma which is exposed to an external source of gamma-rays. The flow is driven by radiative momentum input to the gas, the accelerating force being due to Compton scattering in the relativistic Klein-Nishina limit. The bulk Lorentz factor of the plasma, Gamma, derived as a function of distance from the radiating source, is compared with the corresponding result in the Thomson limit. Depending on the geometry and spectrum of the radiation field, we find that particles are accelerated to the asymptotic Lorentz factor at infinity much more rapidly in the relativistic regime; and the radiation drag is reduced as blueshifted, aberrated photons experience a decreased relativistic cross section and scatter preferentially in the forward direction. The random energy imparted to the plasma by gamma-rays can be converted into bulk motion if the hot particles execute many Larmor orbits before cooling. This `Compton afterburn' may be a supplementary source of momentum if energetic leptons are injected by pair creation, but can be neglected in the case of pure Klein-Nishina scattering. Compton drag by side-scattered radiation is shown to be more important in limiting the bulk Lorentz factor than the finite inertia of the accelerating medium. The processes discussed here may be relevant to a variety of astrophysical situations where luminous compact sources of hard X- and gamma-ray photons are observed, including active galactic nuclei, galactic black hole candidates, and gamma-ray bursts.Comment: LateX, 20 pages, 5 figures, revised version accepted for publication in the Ap

Quantifying overdispersion effects in count regression data

The Poisson regression model is often used as a first model for count data with covariates. Since this model is a GLM with canonical link, regression parameters can be easily fitted using standard software. However the model requires equidispersion, which might not be valid for the data set under consideration. There have been many models proposed in the literature to allow for overdispersion. One such model is the negative binomial regression model. In addition, score tests have been commonly used to detect overdispersion in the data. However these tests do not allow to quantify the effects of overdispersion. In this paper we propose easily interpretable discrepancy measures which allow to quantify the overdispersion effects when comparing a negative binomial regression to Poisson regression. We propose asymptotic $\alpha$-level tests for testing the size of overdispersion effects in terms of the developed discrepancy measures. A graphical display of p-values curves can then be used to allow for an exact quantification of the overdispersion effects. This can lead to a validation of the Poisson regression or a discrimination of the Poisson regression with respect to the negative binomial regression. The proposed asymptotic tests are investigated in small samples using simulation and applied to two examples

The right stuff ‘v’ the right (safe) thing

This is not the 1950’s where test pilots needed the ‘right stuff’ and certainly not the beginning of aviation where the Wright brother’s early designs needed pilots with more than the right stuff. In those formative years of aviation and jet development, designers and pilots did not have the same design understanding and knowledge that we have today. In addition, they did not have the same understanding and knowledge of Systems Safety engineering and Human Factors expertise that we have today. Manned suborbital flights of today should be undertaken in vehicles that have been designed effectively with appropriately derived safety requirements including fault-tolerance, safe life and design-for-minimum risk approaches – and all to an acceptable level of safety. Therefore, although initial suborbital pilots will originate from flight test schools and still possess similar traits to their earlier test pilot brethren, they should be protected by the right (safe) thing by design and analysis rather than rely on the right stuff due to ineffective design and operating procedures. The paper presents a review of the SpaceShip2 accident as a case study to highlight the right (safe) things that should be considered in the design, analysis and operations for suborbital operators. The authors of this paper contend that suborbital piloted vehicles should be designed with the knowledge and understanding and lessons learned from those early X-plane flights, lessons learned from general space safety, lessons learned from pilot Human Factors/Crew Resource Management training and by understanding that safety management and safety engineering are essential disciplines that should be integrated with the design team from the concept phase

Lean Six-Sigma in Aviation Safety: An implementation guide for measuring aviation system’s safety performance

The paper introduces a conceptual framework that could improve the safety performance measurement process and ultimately the aviation system safety performance. The framework provides an implementation guide on how organisations could design and develop a proactive, measurement tool for assessing and measuring the Acceptable Level of Safety Performance (ALoSP) at sigma (σ) level, a statistical measurement unit. In fact, the methodology adapts and combines quality management tools, a leading indicators programme and Lean-Six Sigma methodology to formally measure and continuously improve a stable and in-control safety management process by reducing safety defects and variability from core organisational processes and objectives. The implementation guide was empirically tested and validated with data collected and analysed within a period of nine months by the safety department of a complex aviation organisation operating a large transport aircraft fleet