Those Mysterious Black Panels On The B-21 Raider’s Belly: What They Actually Are

More and more photos of the Northrop Grumman B-21 Raider strategic bomber are being released. Online, some commentators have noticed small, darker panels standing out against the mostly white bomber. In images, four dark square panels can be seen under the nose and four under each side/wing of the aircraft. A bunch of other larger panels are also visible on the underside of the aircraft, making a section of the underbelly resemble a house wall that has only received the primer coat of paint.