NASA on Monday announced a contract award to Lockheed Martin Corp's unit for the preliminary design of a "low boom" flight demonstration aircraft.NASA's Commercial Supersonic Technology Project had asked industry teams to submit design concepts for a test aircraft that can fly at supersonic speeds, creating a supersonic "heartbeat" - a soft thump rather than the disruptive boom currently associated with supersonic flight. (go.nasa.gov/1oTp9h1)NASA said it selected a team led by Lockheed Martin's unit, Lockheed Martin Aeronautics Co, to complete a preliminary design for Quiet Supersonic Technology (QueSST). This is the first in a series of 'X-planes' in NASA's New Aviation Horizons initiative, introduced in the agency's fiscal year 2017 budget.Lockheed Martin will receive about $20 million over 17 months for QueSST preliminary design work, NASA said. Depending on funding, the aircraft will start flight campaign around 2020, NASA said. (Reporting by Radhika Rukmangadhan in Bengaluru)