7d: Colour of American military uniforms (5,4) : o???? ?r?b
18d:Dangerous fungus (7): a??????
27a: Enforcers of naval service (5,4): ??e?? ????
24d: Not flat or natural (5): s???p
26a: Travelling round (9): ????e???t
21a: Short, simple, solo song (7): ??i????