Emirates Team New Zealand have shown the Foiling Gybe in San Francisco Bay. In this video from John Navas, taken bayside in San Francisco, we have the foiling gybe up close.
Also obvious is the technique the team uses to execute the technique. The principal advantage of the move is that the AC72 is able to maintain a much higher speed during the gybe, and this should make a significant gain on a competitor that is unable to properly execute the move. Although the team has never confirmed their ability to do the foiling gybe, speeds through the gybe are understood to be at least 10kts higher, plus the time to accelerate up to full speed out of the gybe is much less.
The downside is the 'S' shaped course, which is slightly longer than the 'L' shaped track taken in a normal style of gybe.
The team has been practicing the maneuver in New Zealand for several months.
The foiling gybe is at 16m.55sec into the 18 minute video, you can see daylight under both hulls throughout the turn.
Also features Oracle Team USA and Emirates Team NZ sailing in lighter conditions in San Francisco on the same day.