Preheat oven to 350 degrees. Grease a 9x5 inch loaf pan.
In a large bowl, stir together flour, oats, salt, cinnamon, and baking powder. Set aside.
In another bowl, stir together sugar, oil, eggs, yogurt, applesauce, and vanilla. Stir in dry ingredients by hand until just combined.
Pour the batter into the loaf pan and bake for about 45-50 minutes, or until a toothpick inserted into the center comes out clean.
Remove from the oven. Let cool slightly.
While bread cools, whisk together the powdered sugar and maple syrup in a bowl. Add a little powdered sugar if it looks too thin. Pour over slightly cooled bread. Let cool completely, then serve.