AEM 121 Introduction to Aerospace Engineering
Glossary
Additional definitions will be added throughout the semester, as new terms are introduced in class.
aeronautics - Aeronautics is the science and engineering of systems capable of achieving flight due to the aerodynamic forces acting upon the system. Examples of aeronautic systems include fixed wing aircraft, rotorcraft, and lighter-than-air vehicles.
aerospace engineering - Aerospace engineering is the field of engineering that focuses on the design, construction, testing, analysis, and operation of aircraft and spacecraft, i.e. vehicular systems that operate within and beyond a planetary atmosphere. Aerospace engineering is an inherently interdisciplinary field that involves, at its core, the study of complex engineering systems and the physical phenomena that affect the behavior of such systems.
astronautics - Astronautics is the science and engineering of systems capable of flight beyond a planetary atmosphere. Examples of astronautic systems including launch vehicles, spacecraft, and other space related technology.
drag - Drag is the aerodynamic force exerted on an aerospace system in the direction "rearward" and parallel to the relative wind. Drag is one of the four principal forces acting on an aerospace system and, in isolation, will decelerate the system. Drag is proportional to the density of the surrounding fluid and to the square of the speed of the system.
engineering - Engineering is the profession that uses mathematical, computational, and/or physical models to create, design, test, analyze, and/or predict the behavior of technology and technological systems. It is a profession that is fundamentally about creating practical knowledge and problem solving.
force - A force is the push or pull experienced by an object during its interaction with another object. When the forces acting on an object are not in balance, i.e. not in equilibrium, the object will accelerate or decelerate. Force is a vector quantity, i.e. it has a magnitude and a direction. In a much broader sense, a force may refer to any phenomenon that is capable of changing the state of the system.
free body diagram - A free body diagram is a schematic representation of the forces and moments acting on an object (including the direction of the forces and moments). Such diagrams are used to conceptualize the impact that support structures, weight, drag, lift, thrust, etc. have on an object.
equilibrium - A system is in equilibrium when all the phenomena that can cause the state of a system to change are in balance. For example, mechanical equilibrium implies that there are no unbalanced forces acting on a system.
lift - Lift is the aerodynamic force exerted on an aerospace system in the direction "upward" and perpendicular to the relative wind. Lift is one of the four principal forces acting on an aerospace system and is used to overcome the weight of the aircraft during flight.
mechanics (engineering) - Engineering mechanics (also known as engineering science or applied physics) is a field of study that focuses on the application of mathematical, scientific, and engineering principles to understand how forces fundamentally affect the behavior and/or motion of a system. Engineering mechanics is the broad foundation on which the study of most engineering disciplines is built.
moment - The term moment refers to the tendency of a force to rotate an object about a specific axis. In the most basic sense, the product of the force acting on the object times the distance between where the force is applied and a reference axis, i.e. the moment arm, defines the moment.
thrust - Thrust is a force acting on an aerospace system that, in isolation, will produce an acceleration of the system in the same direction as the applied thrust. Thrust is one of the four principal forces acting on an aerospace system and is typically used to overcome drag (and/or weight depending upon the direction of flight).
weight - Weight is the force acting on an aerospace system due to the presence of a gravitational force field. Weight is one of the four principal forces acting on an aerospace system and is equal to the product of the mass times the acceleration due to gravity. Weight always acts in the same direction as the vector associated with the acceleration due to gravity, i.e. "downward."
aeronautics - Aeronautics is the science and engineering of systems capable of achieving flight due to the aerodynamic forces acting upon the system. Examples of aeronautic systems include fixed wing aircraft, rotorcraft, and lighter-than-air vehicles.
aerospace engineering - Aerospace engineering is the field of engineering that focuses on the design, construction, testing, analysis, and operation of aircraft and spacecraft, i.e. vehicular systems that operate within and beyond a planetary atmosphere. Aerospace engineering is an inherently interdisciplinary field that involves, at its core, the study of complex engineering systems and the physical phenomena that affect the behavior of such systems.
astronautics - Astronautics is the science and engineering of systems capable of flight beyond a planetary atmosphere. Examples of astronautic systems including launch vehicles, spacecraft, and other space related technology.
drag - Drag is the aerodynamic force exerted on an aerospace system in the direction "rearward" and parallel to the relative wind. Drag is one of the four principal forces acting on an aerospace system and, in isolation, will decelerate the system. Drag is proportional to the density of the surrounding fluid and to the square of the speed of the system.
engineering - Engineering is the profession that uses mathematical, computational, and/or physical models to create, design, test, analyze, and/or predict the behavior of technology and technological systems. It is a profession that is fundamentally about creating practical knowledge and problem solving.
force - A force is the push or pull experienced by an object during its interaction with another object. When the forces acting on an object are not in balance, i.e. not in equilibrium, the object will accelerate or decelerate. Force is a vector quantity, i.e. it has a magnitude and a direction. In a much broader sense, a force may refer to any phenomenon that is capable of changing the state of the system.
free body diagram - A free body diagram is a schematic representation of the forces and moments acting on an object (including the direction of the forces and moments). Such diagrams are used to conceptualize the impact that support structures, weight, drag, lift, thrust, etc. have on an object.
equilibrium - A system is in equilibrium when all the phenomena that can cause the state of a system to change are in balance. For example, mechanical equilibrium implies that there are no unbalanced forces acting on a system.
lift - Lift is the aerodynamic force exerted on an aerospace system in the direction "upward" and perpendicular to the relative wind. Lift is one of the four principal forces acting on an aerospace system and is used to overcome the weight of the aircraft during flight.
mechanics (engineering) - Engineering mechanics (also known as engineering science or applied physics) is a field of study that focuses on the application of mathematical, scientific, and engineering principles to understand how forces fundamentally affect the behavior and/or motion of a system. Engineering mechanics is the broad foundation on which the study of most engineering disciplines is built.
moment - The term moment refers to the tendency of a force to rotate an object about a specific axis. In the most basic sense, the product of the force acting on the object times the distance between where the force is applied and a reference axis, i.e. the moment arm, defines the moment.
thrust - Thrust is a force acting on an aerospace system that, in isolation, will produce an acceleration of the system in the same direction as the applied thrust. Thrust is one of the four principal forces acting on an aerospace system and is typically used to overcome drag (and/or weight depending upon the direction of flight).
weight - Weight is the force acting on an aerospace system due to the presence of a gravitational force field. Weight is one of the four principal forces acting on an aerospace system and is equal to the product of the mass times the acceleration due to gravity. Weight always acts in the same direction as the vector associated with the acceleration due to gravity, i.e. "downward."