Glossary
/EC: “/EC” on Sky-Tec starters means that the unit has “extra cranking”. The aircraft starter which is recommended for aircraft with frequent starting such as at flight schools.
Aircraft Ignition Harness: Shield the high voltage and conducts it to the spark plugs, often bound together. The wires are screened or in a metal braid or conduit to shield the radio against the high frequency ignition interference.
Aircraft Magneto: Part of ignition system on most reciprocating aircraft engines. This part is a self-contained unit which is driven by the engine and produces the electrical current for the engine with no outside source of current.
Bendix Magneto: Part of ignition system on most reciprocating aircraft engines. This part is a self-contained unit which is driven by the engine and produces the electrical current for the engine with no outside source of current.
Boost Pump: An electrical pump, housed in or below the fuel tank, which moves fuel from the tank to the main, engine-driven fuel pump. Also known as a centrifugal pump.
Cam Impulse Spring: Spring inside of the impulse that builds tension as the impulse coupling rotates until the magneto is ready to fire.
Cam Lobe: a rotating or sliding piece in a mechanical linkage used especially in transforming rotary motion into linear motion or vice versa.
Capacitor (Condenser): The component in an airplane magneto that is used to store electrical energy temporarily in an electrical field. It is a passive two-terminal electrical component.
Coil: The part in the aircraft magneto that creates high voltage current necessary to fire a spark plug. The part is made of a soft iron core with two windings of wire around it.
Constant Displacement: A term describing the movement of fuel at the same volume and rate as long as the pump is in operation. This is a feature of Gear type fuel pumps.
Distributor Gear Assembly: Takes the high-voltage electric current from the coil and distributes it to the four electrodes in the distributor block.
Dual Magneto: An airplane magneto which contains one drive source to power both magnetos and therefore firing all sparkplugs and cylinders for the engine.
Engine-Driven Fuel Pump: The primary pump which pressurizes the fuel system and delivers fuel to the engine. The two main types of engine-driven pumps are gear type constant displacement fuel pumps and piston type variable displacement fuel pumps.
Factory Overhaul: A condition description for a part that has been worked on to restore it to factory new conditions.
Ferrule: Combines with the special electrical properties of the coiled conductor for a ground shield and to reduce radio interference. Mechanically secures the wire to the harness cap. This part is found in the terminated ends of aircraft ignition harness leads.
Frame (Housing): The magneto frame is the aluminum alloy shell that houses most of the Bendix Magneto components.
Gear Type Fuel Pump: A type of engine-driven fuel pump consisting of a system of gears that move fuel to the engine. Gear type pumps use constant displacement, which means that while they are in operation, they pump a fixed volume of fuel at a constant rate.
Gravity Feed Fuel System: A characteristic of some high-wing aircraft with fuel tanks situated above the engine, and thus able to feed fuel to the engine using gravity.
Harness Nut: A small metal collar, usually having a hexagonal shape. The nut is used to secure the ignition wire to the spark plug for the aircraft ignition harness.
HT: “-HT” stands for High-Torque which is a category of Sky-Tec Starter.
Ignition Wire: Copper-coated, stainless steel coiled conductor encased in silicone and fiberglass and sheathed by a woven metallic braid impregnated with silicone. The wire in an aircraft ignition harness that carry the charge from the aircraft magneto the cylinder for ignition.
Impulse Coupling Assembly: Enables the magneto to produce sufficient spark for starting the engine. Normally mounted on the left Bendix Magneto only, consists of a main body, cam plate, large coiled spring, and flyweights which pivot on pegs welded to the cam plate.
Insulator: Layer of coating that separates the shielding from the ignition wire. In most aircraft ignition harnesses this layer is made from fiberglass or silicone in order to keep moisture away from the ignition wire and not allow the voltage to escape the ignition wire. Often these are referred to as “cigarettes”.
Key Start: A Sky-Tec starter that uses a key to starter the aircraft starter and automatically engage with the engine on Continental engines.
Magneto: an electric generator that creates periodic pulse of alternating current by using permanent magnets
NL: “-NL” stands for Inline aircraft starters offered by Sky-Tec. This Sky-Tec starter offers a greater gear reduction.
Overhaul: A part that is disassembled and examined, parts are replaced as necessary according to the manufacturer’s overhaul manual.
Piston Type Fuel Pump: A type of engine-driven fuel pump consisting of a plunger system that moves fuel to the engine. Piston type pumps are variable displacement pumps, which means that they can provide fuel to the engine at variable rates.
Points (Contact Breaker): an electrical switch which is used to interrupt the current flowing in the primary circuit. It is found in the distributor side of aircraft magnetos.
Pole Shoes: consist of thin, soft iron plates laminated together. They allow the transfer magnetic flux from the rotor to the iron core of the coil in aircraft magnetos.
Positive Displacement: A term describing the movement of fuel at the same volume for every rotation of a fuel pump. This is a quality of both gear type and piston type pumps.
Primer Pump: A small, hand-operated pump that allows a pilot to move a small amount of fuel to the engine for ignition in cold conditions.
Pull Start: A Sky-Tec starter used on Continental engines where a lever is pulled in order to engage the aircraft starter.
Relief Valve: A feature of gear type constant displacement fuel pumps that allows excess fuel to recirculate into the aircraft fuel system.
Rotor: Rotated in the aircraft magneto by the engine’s accessory drive via the impulse coupling. The central drum of the rotor is magnetized with north and south magnetic poles. The magnetic flux from the rotor is transferred by the pole shoes to the coil.
Shielding: The outer coating of an aircraft ignition harness that protects the insulation and conductor wire. Can be made from a silicone base or metal braiding and is colored based on choice of color of the user.
Single Magneto: An aircraft magneto that is half of the ignition system in one unit and will be paired with another airplane magneto. It fires half of the sparkplugs that go to all of the cylinders in the engines.
Slick Magneto: Part of ignition system on most reciprocating aircraft engines. This part is a self-contained unit which is driven by the engine and produces the electrical current for the engine with no outside source of current.
Swage: To press the individual leads of an aircraft ignition harness into a magneto cap.
Tooth Ring Gears: The gear used to match to the starter adapter for starter and will either be 122-tooth or 149-tooth on Sky-Tec Starters.
Variable Displacement: A term describing the movement of fuel at a variable rate by the engine-driven fuel pump. This is a feature of piston type fuel pumps.