Entire fleets of U.S. Air Force tankers, reconnaissance aircraft and early informing machines have been grounded in fresh weeks due to 1 faulty component of airframes based on the Boeing 707 platform. It required replacement, for example, in 24 of 90 inspected KC-135 Stratotanker tankers, but the issue besides affected the RC-135/WC-135 reconnaissance and key E-3 Sentry for air operations.. It was they who passed the inspection last, but the number of grounded aircraft has not been disclosed.