The Secondary Schools were totally taught by Navy and Marine personnel, and the time was divided between advanced engineering topics and hands-on hardware laboratories. Schools at the NRL (an upgrade from the old RMS), at Treasure Island in the San Francisco Bay, and somewhat later, at Navy Pier in Chicago, were focused on shipboard and shore-based equipment. NATTC Ward Island (described in the next section) was the Secondary School concerned with equipment carried by aircraft. With the students having already been filtered in Pre-Radio and Primary, the pass-rate at the Secondary Schools was comparatively high (about 90 percent), and repeat of one section was allowed.Watson, op. cit. pp. 167–190
