2.3

Question 1

Define bonding

Answer 1

Permanently or temporarily joining metal parts together to keep them at the same level of potential energy, Elminating the risk of sparks between them

Question 2

Define earthing

Answer 2

Establishing a conductive path between a bonded object and earth. The terms earth and ground may be used interchangeably

Question 3

Aircraft and gse are bonded together and to earth to protect pers and equipment from dangers due to

Answer 3

Electrostatic effects

Electrical fault conditions

Question 4

Explain protective equipotential earthing

Answer 4

Prevent Exposed conductive surfaces on structural metalwork from coming live.
Susceptible when 230 volt power cables are brought onboard

Question 5

Types of earthing points

Answer 5

Receptacle/ latching plug

Metal structure/ electrical clip clamp

Question 6

Types of ground/earth points

Answer 6

Permanent- yellow circle with black outline. Test date (every 6months), “static” in red and nato symbol painted on it
Temporary-long spikes that are hammered

Question 7

What’s the maximum length of bonding cable, why? Made of?

Answer 7

Steel wire coz copper melts easily with the massive current. 60m- any longer and it’s internal resistance would be too great the discharge any static build up

Question 8

Types of bonding clips and clamps

Answer 8

Static earth- clip

Protective earthing-trico clamp, ensure on going integrity of connection.

Question 9

When are ac not bonded

Answer 9

Moved
Flight
Connected to a low resistance earth point for electrical safety purposes

Question 10

Single point earthing used when

Answer 10

Parked Ac
Maintenance and servicing without the use of gse
During weapons loading/u loading
When engine driven gse is supplying electrical power to Ac

Question 11

When to dual point earth

Answer 11

During maintenance and servicing of Ac that doesn’t involve highly flammable/combustible fluids when gse is used

Question 12

When to use 3 point earthing

Answer 12

During maintenance/servicing of Ac that involves highly flammable/combustible fluids such as fuel, alcohol, lox/gox, when gse is used

Earthing cable from the fuel nozzle to Ac shall be used

Question 13

Connection sequence for 3 way earth

Answer 13

Ground to Ac
Earth to gse
Gse/fuel nozzle to Ac

Question 14

Why do you need equipotential earthing? Resistance between Ac and earth?

Answer 14

When 230v Power cables are brought inside for supply, they might chafe/cut and an electrical connection opens between power supply and Ac structure.
Resistance dne 0.5ohms

Question 15

What are susceptible to equipotential earthing

Answer 15

Ac

Conductive maintenance docking and scaffolding

Question 16

Earthing requirements when applying electrical power to Ac.
Gpu operation
Hanger mains ground power operation

Answer 16

Gse requiring static earthing must be connected to the static earth point prior to connection to Ac
-Disconnected.

Question 17

What clamp used for equipotential earthing for Ac

Structure around Ac

Answer 17

Trico test clamp

Ce5 clamp