Garmin: Load vs. Activate Approach

"Do I load? Activate? Load? Activate?" - Typical IFR student

Garmin avionics users have certainly experienced the "Load" vs. "Load & Activate" dilemma when programming their Garmin unit for an instrument approach. Garmin's design philosophy exists to facilitate situations where you're expecting an instrument approach but you have not been cleared for it yet.

Scenario

Let's consider a fictitious flight plan from Charleston to Savannah:

KCHS - TERLY - TILLS - KSAV

You're currently flying from TERLY to TILLS, as shown in the image, below. This is what your flight plan and map look like. This is from a GTN 750.

Flight Plan View	Map View

While you fly to TILLS, Savannah Approach tells you "Expect RNAV 10 approach at Savannah". As a good IFR pilot, you want to be ahead of the airplane and prepare the avionics. When you go to the procedures page of the GTN (or G1000, Garmin is the same throughout), you select the RNAV 10 and choose WOXIT as the transition, since it's the most logical choice for your direction of arrival. When you select all the options, you are asked whether you wish to "Load Approach" or "Load Approach & Activate". Which one to choose?? AAAHHH!!! Ok, keep reading.

Loading an Approach

When you select "Load Approach", the entire procedure is appended to the flight plan. Your current flight plan is therefore unchanged. Since you've been told to expect the approach, you are not cleared for it. You need to continue on your current flight plan! Keeping your original flight plan untouched is therefore very important.

However, you also want to have the approach waypoints ready to go! If ATC tells you, proceed direct TELOE, you want to be able to scroll down on the flight plan, select TELOE, and direct-to (super easy, fast, low workload). The alternative is re-loading the approach, which is time consuming and increases workload.

In the below images, you can see how you are still navigating to TILLS, and the approach waypoints are conveniently loaded after the last flight plan waypoint (in this case ,the destination). On the map, you can see how the magenta line still guides you to TILLS, but the approach waypoints are now visible on the map. This provides enhanced situation awareness. When ATC clears you to a waypoint on the procedure and you direct-to, you have "activated" the approach.

Flight Plan View	Map View

Activating the Approach

When you select "Load Approach & Activate", you modify your flight plan - and your guidance - by engaging a direct-to the selected transition.

Let's say ATC tells you "Cleared direct WOXIT, cross WOXIT at 2500, cleared RNAV 10 approach at Savannah". You have been cleared direct-to WOXIT, and your current guidance is now useless. What you would do is "load approach & activate" the approach (assuming you hadn't loaded it already). Since you chose WOXIT as the transition, the activation gives you a direct-to that waypoint. This is what your new flight plan would look like:

Flight Plan View	Map View

Whether you "Activate" the approach (which can be done from the PROC menu or the flight plan menu itself by selecting he approach header) or manually direct-to from the previously loaded approach, the result is the same. The approach is now active.

Other Avionics

Many other avionics handle this situation differently. Honeywell, for example, does not differentiate between loading and activating. The system will replace your destination (KSAV) with the approach. So, if you get to TILLS and haven't been cleared to WOXIT yet, your guidance to KSAV is gone. Many pilots will address that situation by inserting the approach and then modifying the flight plan by re-inserting KSAV or a close-by waypoint (e.g., SAV VOR). This can get tricky if you're too far down the flight plan.