- Ampere
A unit of electric current equal to a flow of one coulomb per second.
- Assembly
Group of machine parts, especially one forming a self-contained, independently mounted unit.
- Blade
Radial airfoil designed to rotate about an axis, as in Propeller, lifting rotor, axial compressor rotor or axial turbine.
- Bonding
Structurally joining parts by adhesive, especially adhesives cured under elevated temperature and/or pressure.
- Castellated Nut
Typically, hexagon nut with six radial slots for split-pin or other lock.
- CHT
Cylinder Head Temperature.
- Cowl
Covering over installed Engine or other device, normally mainly of hinged or removable panels.
- Fixed Pitch
One that has no provision for changing pitch of blades, and hence efficient at only one flight speed.
- Fuel Control Unit
Governs Engine fuel supply in accordance with pilot demand, ambient conditions and Engine limitations.
- Honeycomb
Low-density structural technique and materials based on hexagon-cell honeycomb sandwiched between two sheets too thin for stability alone; can be all metal, or any of the three components can be of various other materials, joined by various adhesives.
- Hub
The central portion of a wheel, propeller, fan, etc, through which the axle passes.
- Mandrel
Centre body, usually circular section, around which tubular or female part is hand-forged, extruded or formed.
- Mixture Control
Manual inceptor formerly included in carburettor to maintain desired mixture as piston engine gains altitude.
- Nozzle
A cylindrical or round spout at the end of a pipe, hose, or tube, used to control a jet of gas or liquid.
- Oil Cooler
Heat exchanger whose purpose is to remove heat from lubricating-oil circuit; usually cooled by air or fuel flow.
- P/N
Part Number.
- Propeller
Rotating hub with helical radial blades converting shaft power into aerodynamic thrust, shaft power provided by human or prime mover.
- Pump
A mechanical device using suction or pressure to raise or move liquids, compress gases, or force air into inflatable objects such as tires.
- RPM
Revolutions per minute.
- S/N
Serial Number.
- Shank
Inner portion of blades where section is not aerodynamic but circular.
- Spinner
Streamlined fairing over Propeller hub; not used for similar fairing over helicopter rotor hub.
- Spar
Main span wise structural member(s) of wing or rotorcraft rotor.
- Spark plug
plugs for spark-ignition engine and those few jet engines where ordinary commercial plug is used; term for gas turbines generally is igniter plug.
- Stick
Control column.
- Starter
Single electrical machine, usually DC, serving both as electrical starter and electrical generator
- Trim tab
Small hinged portion of trailing edge of primary flight-control surface that's setting relative to surface is set by pilot via screw thread, powered trimmer actuator or other system preventing subsequent rotation under air loads and whose effect is to hold main surface in desired neutral position for trimmed flight.
- Vacuum Pump
Device for establishing unidirectional flow of gas molecules and thus of evacuating fixed enclosure; following gross evacuation by mechanical pump alternatives include vapour/diffusion pump, cryopump etc. Also, in aircraft, simple device for applying depression to air-driven flight instruments.
- Valve
Device for controlling fluid flow, into and out of piston-engine cylinder or into/out of aerostat, esp. airship.
- Vernier
Aid to fine adjustment or refined measurement, ege.g. linear scale placed adjacent to main scale, with which, by aligning two corresponding divisions, main scale can be read with enhanced accuracy.
- Yoke
Tie linking helicopter main-rotor blade to Hub.
