Aircraft Electrical Systems What is Electricity?

Electromagnetic Induction was •Electromagnetic Induction - movement of electrons through wires (or conductors) to create . • passed across a closed-loop of wire at right-angles create an (ELF) ELF – VOLTS – occurr when electrons move in the wire

•Vice Versa: Electricity produces magnetism Vice Versa: Electricity produces magnetism Aircraft Electrical System Power Sources Battery

• Provides Electrical Power when or Generator is not available • Several types of Batteries – Most Common – Lead-Acid Battery • Lead and Acid produce electrical charge Electrical battery

• Small, light, not a lot of power • Simple and effective built to last • Recharges during flight from Alternator or Generator Aircraft Electrical System Power Sources Alternator Converts • Alternating Current (AC) to • Direct Current (DC) • For electrical system uses •DC is easier to use, • Lower volts, Safer

•Also, provides Current to Battery to maintain battery power at max levels Aircraft Electrical System Power Sources Generator Produces Direct Current (DC) • For electrical system uses •DC is easier to use, • Lower volts, Safer

•Like Alternator- provides Current to Battery to maintain battery power at max levels when Battery is “off –line” Aircraft Electrical System Controls Aircraft Electrical System Controls Master Switch Controls ALL aircraft electrical power from Source to Use Points

•Left Side Switch controls Alternator Power Source

•Right Side Switch controls Battery Power Source Aircraft Electrical System Controls Circuit Breaker & Fuses •Protect individual electrical User Systems from Electrical Overload (too much power)

•Breakers and Fuses do Same Job •Difference: • Replace a Fuse • Reset a Circuit breakers •Technology Improvement • Fuses- Older Technology • Circuit Breakers – Newer Technology Airplane Electrical Systems Ammeter

•Monitors electrical system performance Two types •To/from battery •Alternator load Aircraft Electrical System Controls

Voltage Regulator • Volt is a measure of Electrical Power • regulator automatically maintains constant voltage level Master Switch Master Solenoid Solenoid Electrical Switch • starter solenoid relays a large electrical current from origination source (Battery or – APU) to rotate Starter Motor Starter Switch Starter

• Electric Motor connected by special gearing to Engine • Rotates at very high speeds to rotate Engine Crankshaft • Engine Crankshaft rotation

• Magneto is a Field Generator – Rotating surrounded by loops of conducting wires • Rotating magnets generate electrical current flow through wires • Aircraft engines have TWO Magnetos for Redundancy – Safety feature – two spark sources are better than one Magneto Systems AND, TWO Spark Plugs

• Two plugs fire simultaneously in Each from Each Spark Source • Efficiency – More even spark – More even, steady burning – More complete burning – Spark improves burning in all areas of cylinder – Plug fouling – A problem Airplane Electrical Systems Battery

•Stores Electricity •Powers Engine •Short-term Power

Magneto and Electrical System

By Cory and Amanda Electrical System- 727 Simplified Magneto and electrical system Jonathan Hord

Magnetoes are self-sufficient Air, fuel and spark starts engine Glass Cockpits

• Electrical power is • Magneto Powered Engine essential for Glass Panel can run without Battery Cockpits power • Glass Panels Can’t Power - Critical

• Backup Battery – 30 Minutes?? Aircraft Electrical Systems

The End – Fly Safe! Basic Electrical/Magneto Aircraft System A cylinder is a central working part of an engine. The space in which a travels. Multiple cylinders are arranged side by side by the . The distance the piston travels in a cylinder is called the . In the cylinder is where combustion occurs. A busbar in electrical power in distributing refers to thick strips of copper and aluminum and conducts electricity within a switchboard, distributing board, or other electrical apparatus. ELECTRICALBrian Bates, Baron Gould, & MAGNETO & Richard Lynch SYSTEMS FOR SMALL AIRCRAFT The Magnetos

• A magneto operates on the principle of electromagnetic induction, is self-contained and engine driven • A magneto provides the electrical power for the to keep the engine running once the engine has been started. • A magneto is a combination of a low voltage alternating current generator and a high voltage coil and . • Timing of magnetos is • The distributor in the magneto determined in the picks up the high voltage development phase. It is current from the coil and important to prevent pre- delivers it through the coil to ignition and/or detonation. the spark plugs. • Small, general aviation aircraft are usually equipped with two magnetos for efficiency, smoother operation of the engine, and redundancy, to prevent the loss of the system if one magneto were to fail (L & R) Alternator or Generator?

• Most small aircraft are equipped with a 28-volt direct current (DC) electrical system, because OR an alternator produces more output for less weight compared to a generator and can produce a specific amount of power at a much lower rotational speed. • An alternator drives the electrical devices and stores energy in the battery. • The battery provides the power to the starter. Electrical System, (in a nutshell)

• The second electrical system connects the electrical buses and the devices to the battery through a switch, the master switch. • The battery provides the power to crank the starter which will start the engine. Now, since the engine is running, the engine will supply power to the alternator and recharge the battery. • The magnetos continually work to create spark, ignite fuel and crank the engine.

• Inside the cockpit, you will find an ammeter • Some instruments require electricity to function Know Your Systems

• Read the pilot’s operating manual (POH) and aircraft flight manual (AFM) to learn how to identify and possibly handle any electrical problem in flight. • In the event of a power failure, you should know whether or not an emergency landing is necessary. • Evaluate Conditions

•VFR or IFR = Nav equipment? •Retractable Gear = extended? • ER Procedures 101 •Flaps retracted or extended? •Transponder/Comms avail? • Aviate • Best Landing Site • Communicate References

Glenn Research Center, http://www.grc.nasa.gov/WWW/K-12/airplane/icengine.html, 1-11-2008 Glenn Research Center, http://www.grc.nasa.gov/WWW/K-12/airplane/elecsys.html, 1-11-2008 Pilot Friend, http://pilotfriend.com/training/flight_training/tech/elec.htm, 1-11-2008 http://selair.selkirk.bc.ca/systems1/Engines/Aircraft%20Magneto%20systems.html, 1-11-2008 Electrical & Magneto Systems

Mark Kinder Nathan Williamson Richard Douglas AVIA 112 Outline

•Electrical Systems •Alternator •Battery •Ammeter •Master Switch •Circuit Breakers & Fuses •Magnetos Airplane Electrical Systems Battery

•Stores Electricity •Powers Engine •Short-term Power Magnetos

• Supplies current to plugs

• Changes mechanical energy to electrical

•Each A/C has 2 magnetos •Provides redundancy •Improves combustion

•Magneto is engine-driven Summary

•Electrical Systems •Alternator •Battery •Ammeter •Master Switch •Circuit Breakers & Fuses •Magnetos Electrical System Magneto Systems Typical Ignition System aircraft electrical systems generate, regulate and distribute electrical power throughout the aircraft. Many aircraft flight instrument systems use electricity •Aircraft electrical components operate on many different both AC and DC •Most aircraft systems use : •115 Volt Alternating Current (AC) @ 400 Hz •28 Volt Direct Current (DC) Most aircraft engines provide power to generate AC generator (alternator) power.

Electrical Systems • The function of the aircraft electrical system is to generate, regulate and distribute electrical power throughout the aircraft. • It is essential for the flight instrument systems. • Aircraft electrical components operate on many different voltages both AC and DC • However, most of the systems use: – 115 VAC @ 400 Hz – 28 VDC • Each of the engines on an aircraft drives an AC generator (alternator). Electrical Power System Components

• AC Generator or Alternator • Constant Speed Drive: in this case would be the driven by the engine. • Today's modern small aircraft contain all of this inside the alternator: – Integrated Drive Generator – Rectifier Unit – Generator Control Unit

Basic Functions

• The basic functions of the electrical system’s components are to: – Generate Power – Control Electrical Power – Protect the Electrical System – Distribute Electrical Power Throughout the Aircraft Magneto How they WoRk! • The ignition magneto combines the functions of a , points, "condenser", and . • The engine spins a magnet inside a coil, and also operates a contact breaker, interrupting the current and causing the voltage to be increased sufficiently to jump a small gap. The spark plugs are connected directly from the magneto output.

All pilots are…

Aircraft Electrical and Magneto Systems

Corey Hjalseth Ali Spirggs Fernando Rodriguez Aircraft Magneto Systems

• A magneto is a combination of low and high voltage current generator and distributor. • The magnetos ignition coil transforms low voltage to high voltage. • The distributor picks up the high voltage from the coils and delivers it to the spark plugs for ignition. Magneto Diagram Aircraft Electrical Systems

• The purpose of an aircraft electrical system is to generate, regulate, and distribute electrical power through the entire aircraft. • It consists of a battery, an alternator, and regulators for these devices. • The alternator charges the battery just like in a . Electrical System Run Through

• The master switch turns on the battery. • The battery turns on all of your aircraft lights. • The Alternator is activated along with the radio and instrument lighting. • The alternator continues to work and recharge the battery and thus light the aircraft. Aircraft Electrical System Diagram General Aviation Aircraft Electrical and Magneto Systems

By: Silvia Fresnedo, Mark Tison and Karen Fisher Electrical System

• The airplanes electrical system consists of a battery and a generator or alternator with associated voltage regulators, current limiters, or other protective devices. • The primary function of the battery is to provide power to the starter motor. • After the engine starts, the magnetos provide ignition, – generator or alternator takes on the tasks of powering: • Radios • Instruments lights • Electrical landing gear • Flaps • Recharging the battery • Individual circuits are protected by circuit breakers or fuses. Electrical System Magneto System

Magneto-equipped aircraft engines are typically dual-plugged, that is, each cylinder has two spark plugs, with each plug having its own separate magneto; This arrangement provides: – redundancy in the event of a failure of one of the magnetos. – more complete and efficient burn of the fuel mixture, and – if placed far apart in the , decreases burn time, allowing higher engine speeds. For this reason, double plugging is also used in high performance automobiles and . Magneto System

Magneto Components Magneto Internals Questions? Electrical and Magneto Systems

Mark, Godfrey, Shane 996 MAGNETO GENERATOR P12W150 835 996 1 MAGNETO P12W150 1 1 821 From serial# 4084219 & above 996 MAGNETO FLYWHEEL 1 Up to serial# 820 4084218 996 COIL KIT P12W150 1 2-5 996-840 2 849 STATOR PLATE ASSY. How the Electrical system works

Aircraft Electrical System Power Sources Alternator Converts • Alternating Current (AC) to • Direct Current (DC) • For electrical system uses •DC is easier to use, • Lower volts, Safer

•Also, provides Current to Battery to maintain battery power at max levels