Sikorsky’s CH-53K King Stallion Lifts Like a Beast

By crosscheckpres on March 11, 2018.

The U.S. Marine Corps is a step closer to taking delivery of a new heavy lift helicopter that will make them the envy of rotorcraft aviators around the world. On February 10, 2018, Sikorsky (a division of Lockheed Martin) performed a maximum performance sling load test as part of its envelope expansion testing for the new CH-53K King Stallion heavy-lift helicopter. The King Stallion is destined to supplant the existing Sikorsky CH-53E Super Stallion in the Marine heavy transport role.

The February 10th test—held at Sikorsky’s flight test facility in West Palm Beach, Florida—lifted a 36,000 pound load and successfully maneuvered both in and out of ground effect. This load is triple what the legacy CH-53E can lift. The total gross weight of the helicopter and the load was 91,000 pounds, which is the highest gross weight ever achieved by a Sikorsky helicopter, and second only to the Russian Mi-26 Halo in vertical lift capability among production model helicopters. View the Sikorsky test video below:

According to Wikipedia, the Sikorsky CH-53K King Stallion is powered by three 7,500 shp General Electric GE38-1B turboshaft engines driving a seven-bladed composite rotor. The design cruising speed is 170 knots, and the service ceiling is 14,400 feet MSL.

Interestingly, the tail rotor on both the CH-53E and K models is canted 20° from vertical. Generally this design feature enlarges the allowable cg range and offers nominal improvements in low-speed stability, but at the expense of significant flight control complexity due to the flight control couplings introduced by the tail rotor vertical lift component.

Stay tuned to the CrossCheck Flight Test Services blog for an upcoming article in the Flight Test Best Practices page concerning helicopter and tilt-rotor sling load testing. Thanks for reading!

Bell V-280 Valor First Flight

In the aviation world, few events are as anticipated, exciting and momentous as the first flight of a new prototype. Bell Helicopter’s V-280 Valor development team experienced that emotional rush on December 18, 2017 when the product of many years’ hard work lifted off the tarmac in Amarillo, Texas for the first time.

Check out this first flight video, courtesy of Bell Helicopter:

The V-280 Valor is Bell’s entry in the U.S. Army’s Future Vertical Lift–Medium (FVL-M) competition to replace the storied UH-60M Blackhawk, and possibly also the AH-64A Apache medium helicopters. The Valor can cruise at 280 knots, nearly double that of the Blackhawk. Additionally, its combat range of 500-800nm is far superior to the UH-60M, and it carries 14 troops, which is 2 more than the Blackhawk.

Bell is competing with the entry from the Boeing-Sikorsky team, the SB-1 Defiant. Also unconventional, the Defiant features a coaxial contra-rotating main rotor paired with a pusher propeller to improve cruising speed and range. The Defiant is expected to begin flight testing later this year.

It will be interesting to watch this procurement battle play out. Whichever team ultimately wins the contract, the U.S. Army will be getting a stellar replacement for the venerable Blackhawk. Furthermore, the boundaries of vertical flight technology will be stretched ever-outward.


Boeing Introduces U.S. Navy Tanker Drone

On December 19, 2017, Boeing unveiled its prototype in the U.S. Navy’s MQ-25 Stingray unmanned tanker drone competition. Boeing’s prototype will compete with entries from Lockheed-Martin and General Atomics. This aircraft will be carrier-based and is expected to have a 15,000lb payload of off-loadable fuel (around 2,300 gallons).

It’s appears to have stealth characteristics designed in, which will make it a nice compliment to the F-35B/C Lightning fighters it will be refueling. It doesn’t make much sense to send stealth fighters off to battle accompanied by refueling tankers that betray the squadron’s position with barndoor-sized RCS signatures!

On the flip side, however, 2,300 gallons isn’t a whole lot of gas for a thirsty squadron of fighter jets! It’ll be interesting to watch this procurement dance play out.