By Mr. Mark Schauer (ATEC)November 13, 2018
YUMA PROVING GROUND, Ariz.-- What has three 7,500 horsepower engines and will ultimately be able to externally carry a 27,000 pound load for 110 nautical miles?
It's the CH-53K King Stallion, the newest iteration of the Marine Corps' heavy lift helicopter, which recently underwent testing at U.S. Army Yuma Proving Ground (YPG).
"It looks very similar to the old CH-53s, but this one is completely new," said Hi-Sing Silen, YPG test officer. "There is such major improvement that it is basically a new aircraft."
The CH-53 type helicopter has been a potent member of the Marine Corps aviation community's fleet for over 40 years, and the newest version takes the platform to a whole new level.
"It's meant to be faster, stronger, lighter, and perform all the duties of the previous iteration with nearly triple the payload capability ," said Silen.
For the men and women who fly the aircraft, however, the most exciting new feature is probably the replacement of hydraulic flight controls with fly-by-wire technology that computerizes the function.
"The benefits of using a computer are that you have less hydraulic fluid and lighter components," said Silen. "You can eliminate pilot errors by enhancing the pilot's ability to operate in different profiles. It's not auto pilot, but a pilot assistance."
"The beauty of fly-by-wire is that when a brownout occurs and the view of the ground goes away, you can put it into a stable hover mode where there is zero drift on the aircraft," added John Rucci, test pilot.
The degraded visual environment course at YPG is highly coveted by helicopter testers seeking to protect flight crews from the potentially catastrophic consequences of brownouts. Caused by rapidly blowing sand and dirt thrown into a vortex by the rotor blades of a helicopter, a brownout's swirling dust gives pilots the illusion they are moving even if they are hovering stationary. Hazardous in any situation, it is particularly risky when landing in a combat zone with multiple other aircraft.
The CH-53K testers reported good results as a result of their evaluations at the proving ground.
"We maintained stability in a hover with very little pilot intervention," said Rucci. "We were able to perform tasks in the hover and do pretty much anything the Marine Corps would want to do with the aircraft in a degraded visual environment."
Silen says that factors such as degraded visual environments underscore the necessity of testing military equipment in the natural environment.
"You have a design on paper and think as an engineer that you accounted for everything, but you have to put it together and use it in the natural environment to verify what you have designed," said Silen. "There is a difference between the notional and the actual."
The 'moon dust' on YPG's DVE course, tilled for maximum diffusion when a helicopter hovers overhead, was adequately harsh for the testers' purposes.
"The view from inside the cockpit in the degraded visual environment here in Yuma was extremely poor," said Rucci. "It was about as bad as any of us have seen in any part of the world."
YPG's contributions to this testing were significantly greater than many other previous helicopter tests here.
"We developed a very elaborate test methodology that is different from the typical test in brownout conditions," said Silen. "We produced an independent link-to-link network from the airfield to the test site for their data acquisition instrumentation to operate from the airfield but talk to the aircraft at the test site. Our range communications personnel gave the customer an independent digital highway that monitored in real time the performance of all aspects of the aircraft."
The experimental nature of the aircraft, which had never before flown in this specific environment prior to its time at YPG, required additional safety measures.
"We had standby crash and rescue personnel on site and at the airfield," said Silen. "It is a new aircraft that had never flown in those conditions, so we took all precautions to rapidly execute emergency procedures if necessary."
Thanks to a carefully executed plan, the test reaped enormous dividends.
"It's a win for the customer based on the amount of data we were able to collect," said Silen.
Overall, the pilots who flew the craft had rave reviews about it and its state-of-the-art capabilities.
"From approach to landing to hover to take-off, the aircraft was incredibly stabile," said Rucci. "This technology will allow the Marine Corps to get in, deliver, and get out of any place in the world they choose to go."