What is the valid ILS localizer coverage area within 10 nautical miles from the transmitter?

The valid Instrument Landing System (ILS) localizer coverage area is significant for ensuring that pilots can effectively utilize this system for precision approaches. The correct answer indicates that the localizer has a coverage area of 35 degrees either side of the runway centerline within a distance of 10 nautical miles from the transmitter.

The ILS localizer operates by providing lateral guidance to pilots during the approach phase of flight, and the specified coverage angle ensures that aircraft can achieve the required lateral alignment with the runway. This 35-degree coverage on each side provides the necessary operational margin for pilots to intercept and track the localizer signal effectively, which is critical for safe landings in low visibility conditions.

The degrees specified represent the angular width of the localizer signal that pilots will need to fly to remain on course. This allows for some deviation from the centerline while still ensuring that the aircraft is within the effective range to receive guidance. The reason why it's essential to have this specific angle defined is to standardize procedures across airports and ensure a uniform level of safety and reliability for approaches using ILS.

A critical point to consider is the reason for the other angles not being correct. Coverage beyond 35 degrees, such as 40 degrees, could lead to increased confusion