You can also click the Add layer mask icon at the bottom of the Layers panel (which, by default, selects Reveal All). Note that if you already have a layer mask on the layer, this icon will change to Add vector mask. Or you can click the Add a Layer Mask icon in the Properties panel.
The top American ace of all time, the U.S. Ace of Aces was Richard Ira Bong. He shot down 40 Japanese planes in the Pacific. Over the years, there's been a lot of ink spilled about the relative scores of German and American aces. 27 Americans shot down over 20 enemy planes.
The Japanese lost, or recorded as lost, 29 planes from the Pearl Harbour attack. Of those, a few were lost because of running out of fuel (could not find their carriers), at least two and perhaps as many as four dive-bombers may have been shot down by Lts Welch and Taylor flying the only two US fighters (P-40s) to get off the ground and score kills, and the remainder were downed by AA fire.