GPS Confusion: There’s Definitely a Myth About ‘Activating the Approach’

When learning the systems of an airplane and the nuances of its avionics, no detail is too small.

Max Trescott

Wednesday, September 10, 2025 at 08:00 AM ET

Verified

Edited By:

Travis Tingle

In today’s glass cockpit world, knowing everything you can about your avionics is as important as knowing how to fly the airplane. [Courtesy: Max Trescott]

Key Takeaways:

Many pilots misunderstand the "ACTIVATE APPROACH" function in GPS navigators, mistakenly believing it's a necessary step for flying an approach.
Activating an approach directs the GPS to draw a straight line from the current position to the Initial Approach Fix (IAF), which can be counterproductive or dangerous if activated when already established on the approach or past the IAF.
This misunderstanding can cause automation surprises, such as an autopilot commanding a 180-degree turn, and is speculated to have contributed to a fatal accident.
Thorough knowledge of avionics and their functions is crucial for pilot safety, especially in modern glass cockpits.

See a mistake? Contact us.

Does that APR, or approach mode key, on your autopilot somehow activate a GPS receiver so it can fly an approach? The answer is no, it doesn’t. And if you’re confused about that, you’re not alone.

And is there something in a GPS receiver that must be “activated” at some point before one can fly an approach? Again, the answer is no. You can fly any instrument approach, either via pilot navigation or vectors and never have to “activate the approach.”