WASHINGTON (Reuters) -The U.S. Air Force has suspended plans it had proposed with Elon Musk's SpaceX to test hypersonic rocket cargo deliveries from a remote Pacific atoll, according to a report this week in Stars and Stripes, an independent publication of the U.S. military. The Air Force had said it would undertake an environmental assessment of the project, but publication of a draft assessment was delayed after opposition to the plan by environmental groups. The Air Force and SpaceX did not immediately respond to requests for comment.