12 Aircraft Magnitism And Deviation

Question 1

Describe the following:

• Soft Magnetism
• Hard Magnetism

Answer 1

• Soft magnetism is temporary

- Hard magnetism is permanent

Question 2

What effect on Deviation will the following have:

• AC orientation
• Latitude of the AC

Answer 2

• If the AC is oriented such that it’s mag field is aligned perpendicular to the Earth’s mag field then deviation will be increased.
• If an AC is flying near the mag poles, where the Earth’s mag field is weakest, then the AC’s constant mag field will have a bigger effect and deviation will be greater.

Question 3

What is a Compass Swing and what are the conditions for it to be performed?

Answer 3

• Compass Swing is a re-calibration of an AC’s compass
• The AC is taxied to a specific area away from anything which would disrupt a compass reading
• All engines and electrical systems are powered up and on
• The AC is then set at different cardinal points and it’s compass reading is then compared

Question 4

What requirements are there to perform a Compass Swing?

Answer 4

• Major change in equipment
• New compass installed
• Struck by lightning
• Parked in the same direction for a long period of time
• Hard landing or shock
• Scheduled maintenance
• Significant deviation has been reported
• Large change in latitude
• AC carrying a specific ferromagnetic cargo