If a pilot is on radar vectors and plans to approach an ILS, what should be done if essential instruments fail?

The best course of action when essential instruments fail while on radar vectors for an ILS (Instrument Landing System) approach is to engage alternate approach procedures with Air Traffic Control (ATC). This decision is rooted in safety and compliance with aviation regulations.

When a pilot experiences instrument failure, they must prioritize flying safely and maintaining control of the aircraft. Communicating with ATC allows the pilot to receive additional guidance and support, which can include alternative approach options or guidance to divert to a safer location. Engaging alternate procedures specifically ensures that the pilot is taking proactive steps to handle the situation in line with established protocols and minimizes the risk of miscommunication or uncoordinated actions.

While other options may seem viable, they do not necessarily provide the structured support and safety net that working with ATC would offer during an emergency situation. Thus, involving ATC is a crucial measure in managing the risks associated with instrument failures during an instrument approach.