Overview
This lecture provides concise definitions and explanations of essential terms and concepts in aerospace engineering, focusing on aircraft systems, navigation, flight dynamics, material properties, and space-related terminology.
Aircraft Components & Controls
- Ailerons control the rolling motion of an aircraft.
- Elevators control the pitch (nose up or down) of an aircraft.
- Flaps increase wing lift and decrease stall speed.
- The cockpit holds the pilot, copilot, and sometimes passengers.
- The fuselage is the main body housing the cabin and cockpit; it's the attachment point for other components.
- Empennage refers to the tail assembly, including stabilizers and rudder.
- Horizontal stabilizer maintains pitch alignment.
- Gliders are engine-less aircraft designed for unpowered flight.
Flight Dynamics & Forces
- Lift is the upward force generated by airflow over the wing.
- Drag opposes the aircraft's thrust and limits speed.
- Angle of attack is the angle between the wing's chord line and relative wind.
- Center of gravity is the common reference point for the aircraft's axes.
- Center of pressure is where the surface area of an object is centered.
- Keel effect helps to stabilize the aircraft, like a weathervane.
Navigation & Instrumentation
- ADF (Automatic Direction Finder) locates NDB (Non-directional Beacon) signals.
- GPS provides precise position, velocity, and time data worldwide.
- DME (Distance Measuring Equipment) measures slant distance from a navigation aid.
- INS (Inertial Navigation System) is a self-contained navigation system.
- ATC (Air Traffic Control) organizes and expedites air traffic.
- IFR (Instrument Flight Rules) govern instrument-based flight procedures.
- ILS (Instrument Landing System) assists with precision landings.
- LAAS provides GPS augmentation for precision operations around airports.
- Dead reckoning is navigation using airspeed, heading, wind, and elapsed time.
Orbital & Space Concepts
- Apogee is the farthest point in orbit from Earth.
- Perigee argument defines orbit’s orientation in its plane.
- Eccentricity measures orbit roundness.
- Geostationary and Low Earth Orbits are specific satellite paths.
- Molniya orbit is highly elliptical and inclined.
- Kessler syndrome predicts collision cascades in orbit.
- Asteroids and comets are solar orbiting bodies of rock, metal, or ice.
Materials & Structures
- Composites are made of fiber layers in a matrix.
- Axial stress acts parallel to the structure's long axis.
- Ductility is the plasticity before failure.
- Modulus of elasticity measures material stiffness.
- Fatigue is failure from repeated loads.
Measurement & Units
- AGL is altitude above ground level.
- MSL is mean sea level.
- Knots measure speed in nautical miles per hour.
- Lapse rate is the temperature decrease with increased altitude.
Key Terms & Definitions
- Aerospace Engineer — Develops technologies for aviation, defense, and space.
- Airfoil — Surface (e.g., wing) generating aerodynamic force.
- Avionics — Onboard electronics for navigation, communication, and control.
- Blind Spot — Area on retina without visual receptors.
- Boundary Layer — Slow air layer next to airfoil surface.
- Inclination — Angle between equatorial plane and orbital plane.
- Indicated Airspeed — Speed reading on the airspeed indicator.
- Mach — Ratio of aircraft speed to speed of sound.
Action Items / Next Steps
- Review and create flashcards for unfamiliar terms.
- Study diagrams of aircraft parts and flight control surfaces.
- Read assigned textbook chapters on flight dynamics and orbital mechanics.