ADF / NDB

What is the term for a direction property error?

• A180° ambiguity
• B90° ambiguity
• Cquadrantal error

An aircraft flying on a heading of 315° will experience maximum quadrantal error from which of the following signals?

• A360°
• B225°
• C135°

Variations in the signal of NDB receivers due to skywaves suggest the presence of:

• Anight effect
• Bcoastal refraction
• Cmountain or terrain effect