Wash, dry, and slice the russet potatoes into uniform half-inch wedges. Pat them dry with a paper towel to remove excess surface starch and moisture.
Place the potatoes directly into the air fryer basket. Drizzle with the oil and sprinkle with sea salt, tossing them well so every piece is lightly coated.
Set the air fryer to 315°F (155°C) and cook for 20 minutes. This low-temperature phase cooks the inside of the potato without burning the outside.
Leave the potatoes in the basket and increase the heat to 400°F (205°C). Cook for an additional 10-15 minutes, shaking the basket halfway through, until the exterior is golden, blistered, and highly crunchy.