Lockheed Martin [LMT] successfully flight tested its VH-92A helicopter on July 28, signaling a major step towards becoming the next Marine One aircraft used to transport the president.

The company’s Sikorsky VH-92A will enter service in 2020, after signing a $1.24 billion contract in May 2014 to produce two test aircraft and four production aircraft as part of the Presidential Helicopter Replacement Program.

Two flights were conducted at the Sikorsky plant in Stratford, Connecticut, according to a Lockheed statement on Aug. 3. The VH-92A will now begin a 250-hour flight test program out of the Lockheed facilities in Owego, New York.

“This first flight of the VH-92A configured test aircraft is an important milestone for the program, Sikorsky’s director of the VH-92A program Spencer Elani said in a statement. “Having independently tested the aircraft’s components and subsystems, we are now moving forward to begin full aircraft system qualification via the flight test program.”

Sikorsky checked hover controls and low speed flight during the two tests.

A second test helicopter is expected to begin flight testing later in 2017.

“With this successful first flight on the books, we look forward to completion of Sikorsky’s flight test program, operational testing and production of this aircraft to support the Office of the President of the United States,” program manager for the Naval Air System Command’s Presidential Helicopter’s Program Office Col. Robert Pridgen said in a statement.