Airplanes and electricity...how does it work?

Question

How do planes get the electricity to power tv's, lights, intercoms, radios, etc? Is there a giant generator or do they collect static electricity in the air? I would love a correct answer with an explanation.

Answer 1

There are alternators on the engines, just like in your car.  Some also have air driven generators, in case the engines fail.  They deploy out of the side of the plane or underneath if the engines fail and there is no electrical power.  They also have methods of changing AC to DC and vice versa.

PS, nick, I have flown planes with air driven generators, also known as RAT's.  They make electricity to provide power to an electric hydraulic pump to provide hydraulic power as well.  But, the RAT, or air driven generator itself only makes electrical power.

Answer 2

Why would it be a "giant" generator?  No.  Each engine has an alternator like the alternator on your car.  When an engine is running, it charges the batteries--again, just like your car.

If an airplane has more than one engine, the electrical system is more complicated than it is on your car, but the basic principle is the same.  A basic course in electricity and electrical circuits will help you most of all.

You can go to the library or the internet and look up "aircraft electrical system."

Other answerers have the terminology backward.  They are, in fact, called "alternators" at Hoover Dam.  Maybe not by tourists, but by the electrical engineers.  And the alternators on the engines of a jet airliner are called "alternators."  The electrical systems distribute both AC (400Hz) and DC current in a variety of ways for various purposes.

Answer 3

They are called generators, not alternators. Alternators deliver DC. They don't call them alternators at the Hoover dam.

They are switched by generator switching relays. As an example, the C130 uses 4 generators. They supply Essential AC, Main AC,  AC left hand Bus and AC right hand bus.

If one is not working, the other generators take over the job via an extensive relay circuit.

For DC, the AC goes to Transformer Rectifiers (TRs) to produce DC and charge the aircraft batteries.

Answer 4

The airplane gets its power from the Engine... as the Engine spools up, it has an onboard generator on each engine and they both are distrubted througout the aircraft to power different things.

When the engines are off and the airplane is on the ground, there is actually another small engine in the tail of the plane called an APU (Auxillary Power Unit) and this is usually running. This engine powers the lights and essential electrics on the ground and also powers up the main engines for starting.

Hope that helps.

Answer 5

Each engine has a generator to provide power to the various electrical systems in the plane. They are split up so no one generator is required to provide too much of the load. They are also designed to provide power to systems not normally powered by that generator in the event one fails. There is no air powered generator. What they are referring to is the RAT or ram air turbine which supplies limited hydraulic power in the event of a system failure. To the person who says I am wrong about the RAT....I installed and tested them when I worked for Boeing. I know what they do and how they work.

Answer 6

Airplanes generators electricity in a similar way that your car generators for your car radio.

Basically, the engines will be connected to some kind of alternator or generator, which is basically a magnet contained inside coils of wire. The engine turns the magnet, and this creates a flow of electricity in the coils of wire.

Also, most large airliners have a smaller jet engine that does not provide thrust, called an  APU or auxiliary power unit.

APU are often used when the aircraft is on the ground, as they can easily be started by the airplane's DC power, and once started, can be used to start up the bigger engines.

Or they can be used to keep all the aircraft lights on when they shut off the engines.

Answer 7

For small plane -there is an alternator

For Narrow and wide body, a generator per engine supplies elect. power. Modern aircraft have an IDG (integral drive generator.) the former is driven by a constant speed drive the latter is now a single unit. Usually generators are rated at 60KVA 115VAC 400Hz. These same generators with cooling can be rated @90KVA 115VAC 400Hz with induced cooling and installed in the APU (auxialliary power unit.)

These same 115VAC goes into a TRU where they are reduced to a 28VDC 400HZ.

In case of loss of engine ergo generator power loss aircraft battery thru inverters can power some navigational equipment use for landing and can power it for 15 mins good for the aircraft to land.

The Ram Air turbine (RAT/CSM generator) in case of hyd loss hyd of green system will be power at the same time a constant speed motor generator will power the aircraft 4.5KVA. This is for A340, A330 while on all other Airbus there is a RAT for Hyd. only.

Answer 8

they dont use static charges.

aircraft dont have giant generotors but the engine are there generators

the genset called alternators used there are using electromagnets and the design made them to loose less energy and thus they are small is size but capable of producing large currents by the use of amplifiers

the aircraft uses the electricity of 115volts with 440hz freequency which gives power desired at lower amperage and  is used parallel by the components making less loss in voltage.

Answer 9

The other guys discussed commercial airliners, but when it comes to small general aviation aircraft, like a Cessna, they use an alternator just like your car does (looks just like your cars, as well.) In you looked under the cowling (hood), you'd find what looks like a lot like a VW engine setup (pardon the comparison! It's just a visual). The one thing that's different is that instead of the alternator giving the spark to the spark plugs, aircraft engines have magnetos, that run mechanically apart from the electrical system (also have two plugs per cylinder instead on one.)

You turn the key and the battery jolts the starter like in your car, while the magnetos begin to turn and provide the spark to the plugs. Once started, the magnetos run the plugs while the alternator runs the radios, lights, certain instruments, etc, in addition to charging the battery back to full charge.

Unlike your car, if the battery goes bad or the alternator give out, or breaks the belt, while your in the air, the engine keeps running and the plane keeps flying. However, if you kept all the radios and lights on, once the battery ran dead, you be flying along deaf (no radio) and with no lights and no transponder to identify you on radar (i.e., you're just a blip, nothing more).

Hope that helps.