What are LP approaches designed to simulate?

LP approaches, or Localizer Performance approaches, are designed to provide lateral guidance similar to that of a Localizer associated with an Instrument Landing System (ILS), but without the vertical guidance component offered by an ILS. These approaches utilize the Localizer signal to navigate laterally to the runway while employing other means, such as a published descent profile or Vertical Navigation (VNAV), to handle vertical descent.

The focus of LP approaches is specifically on their localizer-like characteristics, ensuring pilots can maintain precise lateral tracking during the approach phase. While they may be enhanced by additional technologies or procedures, the core function is to replicate the lateral guidance aspect of localizer approaches, making them effective when ILS is not available, even in challenging conditions.

In summary, LP approaches uniquely offer lateral guidance that simulates the localizer component, while not necessarily providing the full precision of ILS approaches.