Sikorsky’s CH-53K King Stallion heavy-lift helicopter programme for the U.S. Marine Corps has taken a new step forward with the maiden flight of the second CH-53K.

The first and second CH-53K heavy lift helicopter Engineering Development Models (EDM) achieved their first flights on 27th October 2015 and 22nd January 2016, respectively. To date these helicopters have achieved over 35 flight hours combined including multiple flights with an active duty USMC pilot at the controls.

As the flight test programme proceeds, these two helicopters will be joined by two additional aircraft to complete flight qualification of the next-generation heavy-lift capability over an approximately three-year flight test programme.

The first two aircraft are the most heavily instrumented of the EDM models and will focus on structural flight loads and envelope expansion. The first aircraft into the test programme recently achieved flight envelope expansion to 120 knots. When the other two EDM aircraft join the flight line in 2016 they will focus on performance, propulsion and avionics flight qualification.

The King Stallion maintains similar physical dimensions with a reduced "footprint" compared to its predecessor, the three-engine CH-53E Super Stallion, but will more than triple the payload to 27,000 pounds over 110 nautical miles under "high hot" ambient conditions.

The U.S. Department of Defense's programme of record remains at 200 CH-53K aircraft. The Marine Corps intends to stand up eight active duty squadrons, one training squadron, and one reserve squadron to support operational requirements.