Unit 4 Aerospace Terms

Wash In/Wash Out

A built-in twist in the wing where the trailing edge at the wingtip is raised (Wash out) or lowered (Wash in), affecting slow flight and stall characteristics.

Boundary Layers

A thin layer of air next to the surface of an airfoil, which shows a reduction in speed due to the air's viscosity.

Moon

A natural satellite of a planet.

MSL

Mean Sea Level.

NDB

Non-directional Beacon; an L/MF or UHF radio beacon transmitting non-directional signals for aircraft guidance.

NGO

Non-Government Organizations.

Deformation

Any alteration of shape or dimensions of a body caused by stresses, thermal expansion, or moisture change.

Open Loop System

A control circuit where the system output has no effect on the control.

Output

The information produced by a computer.

Moment of Inertia

A mathematical property of a cross section concerning how area is distributed about a centroidal axis.

Perigee

The point in an orbit that is closest to Earth.

Switch

A device for making, breaking, or changing connections in an electrical circuit.

Photopic Vision

Use of color-sensitive cones for direct vision in good light.

Pilotage

Navigation by visual reference to landmarks.

Pitch

Motion around the lateral axis caused by elevator deflection controlled by moving the yoke.

Power Stroke

When the spark plug fires and ignites the compressed mixture to begin the power stroke.

Propellant

A mixture of fuel and oxidizer that burns to produce rocket thrust.

Pupil

The opening in the iris that admits light into the vertebrate eye.

Resilience

A mechanical property showing how effectively a material absorbs mechanical energy without permanent damage.

Retina

The sensory membrane that lines the large posterior chamber of the vertebrate eye, converting images into signals for the brain.

Reynolds Number

The ratio of inertial forces to viscous forces.

Right Ascension of the Ascending Node (RAAN)

The angle along the equatorial plane between a fixed reference point and the point on the orbit where motion crosses the equator.

Turbojet

A type of gas turbine engine with no bypass.

Syntax

The set of rules defining the combinations of symbols in programming languages.

TACAN

Tactical Air Navigation; an electronic rho-theta air navigation aid providing bearing and distance to the TACAN station.

Turboprop

A turbojet engine with a propeller mounted on the shaft ahead of the inlet.