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It is expected for pilots to apply wind correction angles to the aircraft heading while following the tracks depicted in a procedure, as described in PANS-OPS, (Doc 8168), Procedures for Air Navigation Services — Aircraft Operations.
How is this practice reflected in real world while tracking to or from a NDB?
• A
Once the aircraft is established on the depicted track the head or tail of the needle will point straight up on the instrument regardless of wind conditions.
• B
The head of the needle will be pointing at 3600 when the aircraft is established on the inbound or outbound track.
• C
The head or tail of the needle may point slightly left or right of the top of the instrument when maintaining the appropriate QDM or QDR.
• D
The relative bearing will be equal to the wind correction angle required to maintain the depicted track towards or away from the NDB.

Refer to figure.
The needle of an ADF always points towards the NDB that it is tuned into. Relative bearings are measured from the aircraft heading (to the NDB). When tracking towards a NDB, the relative bearing equals to 360 degrees minus wind correction angle. When tracking away from a NDB, the relative bearing equals to 180 degrees minus wind correction angle. Note the wind correction angle is added to track to give headings.

• It can be seen that the head or tail of the needle need not be pointing straight up when there’s wind to correct for. Hence “Once the aircraft is established on the depicted track the head or tail of the needle will point straight up on the instrument regardless of wind conditions.” is not the correct option.
• Even if there’s no wind, the head of the needle will be pointing at 180 degrees (relative to the top of the instrument) when tracking outbound of NDB. Thus “The head of the needle will be pointing at 3600 when the aircraft is established on the inbound or outbound track.” is incorrect.
• From the diagram it is clear that relative bearing only equals to the magnitude of the wind correction angle when tracking inbound and the wind correction angle is negative. Therefore, “The relative bearing will be equal to the wind correction angle required to maintain the depicted track towards or away from the NDB.” is incorrect as well.
• The only option left is “The head or tail of the needle may point slightly left or right of the top of the instrument when maintaining the appropriate QDM or QDR.” which is correct when crosswind is light. When crosswind is strong, the head or tail of the needle may point significantly from the left or right of the instrument though when maintaining the appropriate QDM or QDR. However, it is the most sensible answer choice present in this question.

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