Gary Hamann, Infinite Flight ATC Supervisor and veteran controller, on the advantages of using the S-Approach strategy:
There are a number of advantages with this strategy…
- Keeps everyone relatively close to the airport, allowing you to manage the airspace without zooming all over the place.
- Following each clear, you only have to manage the turns. It becomes mechanical… clear someone, manage your turn points, go back and clear the next one or 2 depending on the number of runways.
- I give each leg a unique altitude, making it easy to tell if someone has missed a turn. Believe it or not, sometimes people get distracted and miss a turn. I can turn the following plane early and insert the guy that missed his turn one plane back.
- Since each leg has a unique altitude it’s straight forward to handle emergencies. I can immediately turn someone in the upwind leg toward the airport knowing separation won’t be an issue. If I’ve got someone flying faster than everyone else, I can recycle him to the end without separation issues.
it’s easy to manage separation by extending or cutting a turn short. If you have a single long line, and someone drops out for whatever reason, it’s next to impossible to make up that gap in the line.
- Adding someone to the middle of the line is straight forward as you can extend a turn point and insert the new guy at the next leg. This occurs when you’ve got people arriving from different directions.
The approach consists of four legs forming an S, hence the name. Here’s an example of what that looks like. Gary goes on to note:
This strategy evolves during a session. If traffic is light, I’ll give everyone a direct approach. As traffic builds, I’ll add a downwind leg. More traffic, add the upwind leg. Traffic dies down, eliminate legs. Ideally you make these adjustments while maintaining a consistent separation on final.