Rinse and slice them thin. Lay on paper towels and press moisture off so they are dry and oil will stick well. Preheat air fryer for 5 minutes at 380 degrees F.
Put slices into a bowl and drizzle with oil. Toss to coat. Pour into basket and shake so they are in a single layer. Sprinkle top with salt.
Air fry for 6-10 minutes depending on how crispy you want them to be and how thick they were sliced.