DENVER -- Senior Air Force leaders disclosed that negotiations with Boeing to contract for the first E-7A Wedgetail aircraft have been "difficult" due to non-recurring engineering development. An initial contract was signed last year , but negotiations on cost are ongoing for the first two rapid prototype platforms, service Secretary Frank Kendall told reporters today at the Air and Space Forces Association Air Warfare Symposium . “We’re having a hard time with that one getting price agreement with Boeing,” Kendall...