* The Sikorsky company of the USA was a pioneer in modern helicopter development. In the 1970s, Sikorsky continued its tradition of excellent rotorcraft by developing the twin-engine "S-70" military utility helicopter, which went into US Army service as the "UH-60 Black Hawk", and the similar "S-70B" naval helicopter, which went into US Navy service as the "SH-60 Seahawk". They remain in service, with Sikorsky -- as of 2015, an arm of US defense giant Lockheed Martin -- continuing to introduce new variants. This document provides a history and description of the S-70 / S-70B family of helicopters.