Unit 1-10 Part 1

Question 1

What are power distribution systems?

Answer 1

One or more electrical connections to disperse electrical power
Power must be distributed where it is needed
Employed in virtually all electrical devices

Question 2

How is power distributed on an aircraft?*

Answer 2

Often use a solid copper bar (a bus or bus bar)
Could be a simple terminal (connection point) connecting several wires

Question 3

What is a single wire system?*

What kind of aircraft uses it?*

Answer 3

The airframe is ground and distributes the negative voltage
Metal airframe is referred to the ground system

Metal/aluminum aircraft

Question 4

What is a two wire system?*

What kind of aircraft uses it?*

Answer 4

Both positive and negative voltage must have a distribution system
Need ground conductor to complete the loop because the airframe itself is not a conductor

Composite aircraft

Question 5

What is bus hierarchy?*

What is its purpose?*

Answer 5

A design concept

To ensure the most critical distribution bus is the least likely to loose electric power

Question 6

What is the most important distribution bus?*

Answer 6

Hot battery bus
Connected to:
Aircraft battery
Critical systems (fire protection & fuel pumps