Understanding Radar Vectors and Their Role in Aviation

Radar vectors play a crucial role in aviation, especially for aircraft approaching airports without an Instrument Landing System (ILS). These vectors, which are headings given by Air Traffic Controllers (ATC) to pilots, serve as a means to guide aircraft to a safe landing. However, the applicability of radar vectors varies among different airports and airfields. This article explores the concept of radar vectors, their usage in airports without an ILS, and the associated procedures.

What is a Radar Vector?

A radar vector is a series of headings issued by ATC to pilots to position the aircraft for an approach, final approach, or any other navigational purpose. These vectors are not intended as a substitute for ILS. Instead, they guide the aircraft to a point where it can then proceed with a normal instrument or visual approach.

Types of Approach Without ILS

Several methods can be used to approach an airport without an ILS. These include:

Standard Terminal Arrival Route (STAR): A pre-programmed course that helps guide an aircraft from the terminal area to the airport's outer or initial approach course. Full Approach with Procedure Turn: This involves a procedure turn to intercept the final approach course. Radar Vectors: ATC provides a series of headings to guide the aircraft to the final approach fix (FAF).

Radar Vectors and the Final Approach Fix (FAF)

The final approach fix (FAF) is the last navigational point that an aircraft must pass before the final approach begins. Radar vectors are typically used to get the aircraft to this point. Once the aircraft reaches the FAF, it can then proceed with the normal instrument approach procedures.

Usage of Radar Vectors in Civilian Airports

While radar vectors are commonly used in civilian airports, the precision required for a full instrument approach to land is not always available. Civilian airports generally do not have the specialized radar equipment necessary for Ground-Controlled Approach (GCA), which provides both heading and altitude information all the way down to landing. Instead, radar vectors only bring the aircraft into the vicinity of the approach course.

Example of Radar Vectors at Heathrow Airport

In the UK, Heathrow Airport is a prime example of where radar vectors are frequently used. Immediately after leaving certain waypoints, aircraft are given vectors to guide them onto the Instrument Landing System (ILS). For instance:

"BAW123 leave Ockham heading this is the vector being given 075 descend FL X."

This vector ensures that aircraft can descend and approach the ILS. Using radar vectors at Heathrow has several advantages, including improved separation between aircraft, quicker and safer changes to the approach, and the ability to adapt the approach as needed.

Radar Vectors vs. Instrument Landing System (ILS)

While radar vectors are a useful tool, they are not a substitute for the precision provided by an ILS. An ILS provides a clear and precise signal for a safe landing, while radar vectors provide guidance to the vicinity of the approach course. Once the aircraft reaches the FAF, it can then use the ILS for the final approach and landing.

Ground-Controlled Approach (GCA)

Some military airfields use Ground-Controlled Approach (GCA), which provides a more precise radar vectored approach all the way to landing. GCA requires specialized radar equipment that is not typically found in civilian airports. This method can offer both heading and altitude information to help guide an aircraft safely to the runway, but it is not widely available in civilian aviation.

Conclusion

Radar vectors are a critical tool for aviation, especially in airports without an ILS. They provide guidance to the FAF and can help ensure the safe and efficient approach to landing. While they are not a substitute for an ILS in terms of precision, they are an effective method for guiding aircraft in a variety of scenarios. Understanding their usage and limitations is essential for pilots and air traffic controllers alike.