Weapons Survivability Lab Marks 50 Years

An aerial view of the nine-engine Super HVAS at the WSL. (U.S. Navy photo by WSL Photo Team)

For 50 years, the Weapons Survivability Laboratory (WSL) at China Lake, California, has played a crucial role in making naval aircraft safer and more survivable in a crash.

Since 1970, the Naval Air Warfare Center Weapons Division’s (NAWCWD) WSL has discovered and resolved vulnerabilities in aircraft before sending naval aviators into enemy territory. Could a rocket-propelled grenade fired at a flying jet’s fuel tank bring the plane down? WSL conducts tests, analyzes what happened and provides data so aircraft designers can do their best to ensure the answer to that question, and many more, is “no.”

A T-33B aircraft is set up for a test at the WSL’s original two-engine High Velocity Airflow System (HIVAS) circa 1975. (U.S. Navy photo)

“I’m always impressed with the passion and dedication of the people working in the survivability discipline,” said Chuck Frankenberger, WSL lead. “That passion provided a great foundation, and it’s alive and well in the workforce today. We continue to expand that foundation by keeping up with or ahead of new aircraft and threat technologies, providing the most survivable aircraft to our warfighters.”

Today, WSL has five primary test sites that can accommodate anything from small, unmanned air vehicles to jumbo-sized transports.

An A-4 Skyhawk undergoes fuel system evaluations at the Weapons Survivability Laboratory (WSL). (U.S. Navy photo)

Naval Air Systems Command initiated the Aircraft Survivability Program in 1969 after survivability issues plagued aircraft from World War I through the Vietnam War. In particular, more than 5,000 aircraft were lost to small arms in Southeast Asia, and there were more than 30,000 incidents of combat damage.

That same year, what was then the Naval Weapons Center (NWC) was chosen as the lead laboratory to conduct research and development work to understand vulnerability and survivability on Navy combat aircraft, such as the A-4 Skyhawk, F-4 Phantom, F-14 Tomcat and A-7 Corsair.

In 1970, NWC started the Vulnerability/Survivability Gun Range and completed its first live-fire test site. The A-4 Skyhawk was the first aircraft tested, marking the beginning of a 50-year tradition of evaluating the lethality of foreign threats against U.S. aircraft and finding potential vulnerabilities.

But it soon became obvious there were limits to testing capabilities, mainly, that planes in flight move through the air at hundreds of miles per hour, while planes on the ground are in still air. Enter the High Velocity Airflow System (HIVAS).

The facility’s first HIVAS was completed in 1975 to provide realistic conditions for live-fire testing. The system simulates in-flight airflow conditions over aircraft surfaces or through internal compartments or engine inlets.

Over the ensuing years, the Aircraft Survivability Range expanded its focus, combining live-fire testing and analysis for a model-test-model approach to identify and test vulnerabilities, then make recommendations on how to fix them. In 1980, the name changed to the Weapons Survivability Laboratory.

Survivability testing, of which WSL is at the forefront, is so vital that the Department of Defense 5000 series of directives in 1991 mandated survivability as a critical system characteristic when acquiring weapons systems. Also, federal law requires realistic survivability testing be done before production ramps up.

An F-14 MANPADS (man-portable air defense system) is tested in static condition, tower mounted at the WSL. (U.S. Navy photo)

As the times change, so does WSL. The first HIVAS used two turbofan engines; today, WSL has a four-engine HIVAS and a nine-engine Super HIVAS, which allows air to move at up to Mach 0.82. In addition to blowing air over wings, the systems enable testing of aerodynamics, flares and rocket motors, stores ejection and separations, seat ejections and parachute deployment, among others.

By performing these tests on the ground with remote controls and full instrumentation, WSL conducts evaluations that would be difficult or impossible to complete safely and cost effectively. As demonstrated over the last 50 years, WSL will continue to adapt to ever-changing conditions to protect America’s forces from threats old and new.

Written by Aaron Crutchfield with Naval Air Warfare Center Weapons Division Public Affairs.

Navy, Air Force Collaborate on Engine Testing Remotely

A Pratt & Whitney F135 engine is fired in a J-2 test cell at the Arnold Engineering Development Complex (AEDC), Arnold Air Force Base, Tenn. When the Remote Data Room at the Propulsion Systems Evaluation Facility at Naval Air Station (NAS) Patuxent River is connected to the AEDC this fall, engineers at both sites will collaborate on testing the engine. (U.S. Air Force photo)

A year in the making, engineers from the Propulsion Systems Evaluation Facility (PSEF) at Naval Air Station Patuxent River, Maryland, and engineers at the Arnold Engineering Development Complex (AEDC) at Arnold Air Force Base, Tennessee, will soon be collaborating on a first-of-its-kind endeavor.

In September, Leo Rubio, a test engineer with the Naval Air Warfare Center Aircraft Division’s (NAWCAD) PSEF at Pax River, will join forces with engineers at AEDC to run a test and analyze the data on a Pratt & Whitney F135, the engine that powers all three variants of the F-35 Lightning II. What makes this particular test unique is that Rubio will be watching and participating from the new Remote Data Room in Maryland while the other engineers, and the engine, will be 700 miles away in Tennessee.

Located inside PSEF, the Remote Data Room—which currently comprises four monitors and two keyboards—allows a test analyst at Pax River to act as a remote team member during a live engine test taking place at the AEDC and view the data being collected.

“One thing we worried about was the latency when working in real time; will there be dropouts or will we see a number of data points from a minute ago or a second ago,” said John Kelly, branch head for Test Operations and Facilities Engineering at Pax River. “But, so far, with just the few trials we’ve run, it’s milliseconds. Now that the proof of concept is real, we’re pushing forward and building an actual dedicated room with four work stations and two big screen TVs so we can see the engine running in the test cell; and we’ll do a Skype setup so we can also see each other.”

The Remote Data Room is saving time and money. In the past, if the Navy needed to help support an engine test, they would have to pay travel expenses and send personnel to AEDC.

“Even then, we wouldn’t be qualified to sit and analyze data with the test team,” Kelly said. “We’d be more of an observer, or the customer, waiting for data. But now, we’ll be more integrated; we’re one of the test team people watching with this data room.”

That’s where Rubio plays a big part, having recently completed AEDC’s Aeropropulsion Combined Test Force Basic-Level Training curriculum.

Advancing Technical Skill Sets

In 2019, Rubio was sent to the AEDC facility—which operates more than 60 aerodynamic and propulsion wind tunnels, rocket and turbine engine test cells and other specialized units—to support the Navy’s MQ-25 Stingray program and observe an altitude test for the AE3007N engine.

“The goal was to work with my counterpart at AEDC, Seth Beaman, to develop a training curriculum to get NAVAIR personnel certified as basic-level analysts,” Rubio said. “I ended up integrating myself well with the test team and taking on more of the training and serving as a test analyst during all of their air periods for this test program.”

AEDC has training standards they follow, and the engineers worked to determine what portion of those standards applied to Navy employees, whether they are present at AEDC or remotely supporting a test from PSEF, Beaman said. The curriculum the team developed will ultimately help advance the workforce and enable them to more quickly respond to critical evolving requirements of current and future programs like F-35.

“Any engineers [at Pax River] who will be coming down here or who will be remotely supporting will be going through that training program at some point,” said Beaman, a test analyst and one of 10 NAVAIR employees with the Aeropropulsion Combined Test Force who work with the Air Force at AEDC.

Improved Speed and Readiness

With the Navy’s combined interest in some of the engine testing being done at AEDC, the Remote Data Room offers NAWCAD engineers the ability to access data, not only in real time while seeing the test, but also by accessing historical data without having to call down to Tennessee for assistance.

“[In the past], there wouldn’t have been much communication between any type of testing [at AEDC] and what they were doing at Pax,” Beaman said. “If they were interested in accessing data, they maybe would’ve called a branch chief here to request it, but the lead time required gathering, analyzing and reporting the data before sharing. Now, [with the Remote Data Room connection] if Leo wants to access AEDC data, he just has to log in and he’ll have access to plot any type of historical data he’d need to reference.”

In a move benefitting both sides, the analysis group in Tennessee assigned a certain objective, or portion of the upcoming F135 test, to Rubio, who will analyze fan duct heat exchanger effectiveness.

“We have certain objectives we’re trying to accomplish, and with Leo responsible for an objective, it will give him the work he needs to gain experience while [simultaneously] offloading a little of the work from the analysis force here at AEDC,” Beaman said. “That gives us time to do a more thorough analysis on the remaining objectives. Ultimately, this will yield more quality and quicker post-test reports.”

In fact, the biggest winners in all of this may be the engineers themselves.

“This is a remarkable opportunity for engineers at Pax,” Rubio said. “We primarily deal with turboshaft engines in PSEF whereas AEDC deals with turbofan and turbojet engines. This allows our folks to get a greater variety of testing experience and encourages more of a collaborative effort. Also, rather than having data forwarded to our teams here for an engine test they may have some stake in, they can access live test data and perform their own analysis much faster and with some elaborate tools that AEDC engineers have at their disposal.”

Kelly also noted another plus to engineers comes in their role as the voice of the Navy when talking to original engine manufacturers (OEM), such as Pratt & Whitney, Rolls Royce or GE.

“One of the best ways to get a PSEF engineer knowledgeable on an engine is through doing the testing where you can really see how it operates—the good stuff and the faults,” Kelly said. “It’s a better in-depth understanding of the engine versus just studying what the engine is supposed to do. So, if we have engineers going through this training and learning what the engine is, they’ll be much more knowledgeable at their job and work better with the OEMs.”

“It’s definitely like a ‘Field of Dreams’ thing: ‘build it and they will come,’” Kelly said. “We know as soon as we get it going, everyone will be saying, ‘Really? I want to see this.’ I’m expecting it’ll keep building the more we use it.”

Even as the team starts up the Remote Data Room, they’re certain it will generate interest beyond their own division.

Donna Cipolloni is editor of the Tester newspaper and supports NAS Patuxent River Public Affairs

Navy Test Engineers to Regain Hands-on Experience

Leo Rubio, seated, Propulsion & Power test engineer, shows John Kelly, Test Operations and Facilities Engineering branch head, data plots from historical engine data acquired at the AEDC using the Remote Data Room set up at NAS Patuxent River. (U.S. Navy photo by Adam Skoczylas)

The idea of the Remote Data Room was kicked into action when John Kelly, branch head for Test Operations and Facilities Engineering, arrived at the Propulsion Systems Evaluation Facility (PSEF) a couple years ago. He was tasked by his former boss Tony Miguelez, who is now the Fleet Support Team Executive/Chief Engineer, Fleet Readiness Center Commands, to bring the room to life.

“It was his concept,” Kelly said. “Miguelez was from the generation who came through [Naval Air Warfare Center] Trenton and did a lot of testing. He came up through the ranks and I think he recognized the value of the knowledge that experience gives a test engineer.”

Following a Base Realignment and Closure Act (BRAC) decision that shuttered the Trenton facility in the late 1990s, DOD decided all turbo shaft and turbo prop work would come to the Navy at Pax River, while turbo jet work went to the Air Force at Arnold Air Force Base, Tennessee.

Tom Weiss, division head for Propulsion and Power’s Test Methods and Facilities Division, said when Propulsion and Power lost the ability to do altitude testing in house as part of that BRAC, new engineers coming aboard lost the ability to look at data, make decisions based on the data and really understand the inner workings of an engine.

“Anybody who’s an engineer who has spent part of their career doing flight test, ground test or anything where you’ve really had your hands into it understands the product much better than by just watching what others are doing,” Weiss said. “With the Remote Data Room, I think we’ll get that back.”

Weiss also noted with AEDC’s shift from contractors toward the government workforce taking over data analysis in reporting, the need for a highly trained government workforce has increased.

“As need continues to grow, AEDC will not be able to staff up because of financial limitations within the Air Force,” Weiss said. “This Remote Data Room will come in to play with the Navy augmenting their ability to conduct these tests on time and within budget. This is a great opportunity for both workforces to grow technically  and collaborate.” — Donna Cipolloni    

Grampa Pettibone

Gramps from Yesteryear: March-April 2001

Illustration by Ted Wilbur

Wild Winds

Editor’s note: Lt. Cmdr. Howard M. Tillison, USNR (Ret.), was officer in charge of Helicopter Antisubmarine Squadron (Light) (HSL) 30 Det A aboard USNS Harkness (T-AGS-32) in 1982 during the incident he describes here.

We were inbound in our HH-2D Seasprite to a promising landing zone (LZ) which was on a gently sloping coastal plane in the lee of a mountain range that rose from sea level to 3,000 feet within a couple of miles. Inbound to the LZ from the ship at 1,500 feet we had a 25-knot head wind, shown by comparing our airspeed and doppler ground speed indications. When I reached a good spot to begin a straight-in landing approach to the LZ, I started a normal descent and began reducing airspeed from 100 to 70 knots for a straight-in to final. We were attempting to land as closely as possible to a road which ran along the base of the mountains at the spot where they began their upward thrust from the coastal plain.

I suddenly noticed that things didn’t feel right. I looked down to see a 1,500-feet-per-minute rate of descent on the vertical speed indicator. My ground speed was also increasing and the mountains were getting bigger all the time. In the space of about a mile, the wind had shifted 180 degrees and was now dead on the tail. Instead of a straight-in to the LZ, I ended up button-hooking around. I landed uneventfully, facing back toward the ocean.

After analyzing the situation, my copilot and I realized that the easterly tradewinds were spilling over the ridge and forming a rotor in the lee of the mountains, which resulted in both a downdraft during our approach and a 180-degree wind shift at ground level. Luckily, we were lightly loaded, overpowered and had room to recover from a potentially hazardous situation by making a 180-degree turn prior to landing. If we had been heavy and failed to notice the wind shift prior to short final, we could just as easily have been in a settling-with-power, or power-settling (remember the tailwind) situation.

After that experience, we either had our ground party pop a smoke flare every time we approached an LZ in mountainous terrain, or we conducted a flyover at 1,500 feet and tossed out a roll of toilet paper to see what the winds were doing at ground level before commencing our approach.

Mountain flying is a different environment, even when the mountains are right there next to the friendly ocean and flat tropical beaches. Helo drivers should be aware of this potential problem before attempting to land on the lee side of a mountain and ending up with a tailwind instead of a head wind while trying to pull into a hover.

Gramps blamed the CH-53D Sea Stallion crew in “Lava Lament” (see Grampa Pettibone, Spring 2020) for failing to “determine the wind direction,” but it’s not always apparent when the wind has shifted 180 degrees as it did with me and probably did to the CH-53D pilots that day, in a relatively small space. If a Hornet is on final to a carrier and the winds go out of limits, the air boss or the landing signal officer can wave it off. It ain’t the same ball game when you’re in a helo trying to make it into an LZ without the benefit of having somebody on the ground to put up a windsock before you arrive.

Grampaw Pettibone says …

“Welcome advice for rotary wing pilots.”

Investigators Find No Root Cause of Physiological Episodes, Identify Physiological Degraders

U.S. Navy photo illustration by Fred Flerlage

Naval Aviation’s Root Cause Corrective Action (RCCA) analysis teams concluded their investigations in December and found no single root cause for Physiological Episodes (PEs) experienced by naval aviators.

They determined, however, that PEs may result from a “stacking of physiological degraders,” according to Rear Adm. Fredrick Luchtman, Commander, Naval Safety Center, and Physiological Episodes Action Team (PEAT) lead.

Each RCCA core team—one for the T-45 Goshawk training jet and another for F/A-18 Hornet and Super Hornet and EA-18G Growler jets—included Naval Air Systems Command (NAVAIR) engineers along with instructor pilots, independent doctors and scientists, along with support from dozens of other subject matter experts.

PEs remain Naval Aviation’s No. 1 priority, Luchtman said.

To mitigate risk, the PEAT and program offices have developed tools and upgraded equipment in the T-45, the F/A-18 and EA-18G.

“The good news is the rate of PEs in the T-45 has gone down 90 percent since the peak rate in March of 2017. For the F-18, the rate has gone down 59 percent since the peak rate in November 2017,” Luchtman said.

He attributes those decreases to new tools and upgrades specific to each aircraft.

His focus now is on air crew awareness, proper equipment fit and educating aviators on how to maximize their physical condition to better withstand the hostile environment in the cockpit.

Physiological Margins

“We have validated that there are some factors—such as hydration, nutrition, sleep, physical conditioning and stress—that enable one to be more resilient in the cockpit,” he said.

“If you can maximize hydration, nutrition and rest, and minimize stress, you make yourself more resilient and able to handle the hostile cockpit environment,” he said.

He compared an aviator’s physiological margin to a suit of armor.

The rate of physiological episodes has gone down 59 percent since its peak in November 2017 for the F/A-18E/F Super Hornet (U.S. Air Force photo by Staff Sgt. Matthew Lotz).

“We call the depth of that armor the physiological margin. It is how well you are prepared to handle an anomaly in the cockpit. Like professional athletes, we need to understand our own physiology and how to maximize our own physiological margin.”

While it is difficult to quantify human performance aspects, the topic of physiological margins and equipment fit have been the focus of the PEAT’s roadshows. The roadshows are designed to keep aviators informed of the PEAT’s findings and aware of upcoming changes before they are published in the Naval Air Training and Operating Procedures Standardization.

Feedback from pilots during the roadshows on the human performance aspects have been mixed, he said.

Rear Adm. Fredrick Luchtman, Physiological Episodes Action Team lead, visited Naval Medical Research Unit Dayton (NAMRU-Dayton) Nov. 4 and experienced the scientific force that is the one-of-a-kind research device called the Kraken. A pilot himself, Luchtman donned his flight suit and strapped into the capsule to experience a profile that addresses pilot spatial disorientation. (U.S. Navy photos)

“There is some level of frustration that there is no single root cause, no smoking gun. But when we walk through the scenario and talk about how one can get to a degraded state in the cockpit based on these physiological aspects adding up, they start nodding their heads,” he said.

Naval Aviation has made it look effortless, he added.

“We have done ourselves a disservice in Naval Aviation by making this look so easy, when in fact this is a hard job in a very demanding and hostile environment where incredible G-forces, temperature variations and an almost overwhelming amount of sensory input are placed upon you. The better physical shape you are in, the better you’ll be able to withstand those demands,” he said.

When physiological degraders add up, they may result in a PE, which applies to either breathing dynamics and hypoxia events, or pressure-related events that result from fluctuating cabin pressure caused by sub performing parts in the Super Hornet’s Environmental Control System (ECS).

“We want to keep parts from failing, but in the event they do fail, aviators can protect themselves even more by making sure they’ve stacked up their physiological margin,” Luchtman said.

Equipment Fit

In April 2018, the RCCA team identified gear fit as a contributing factor to PEs.

If the flight harness is worn too tight or the straps are in the wrong places, it can inhibit the aviator’s ability to take a full, deep breath.

“If you can’t take a deep breath, that becomes a physiological degrader and reduces one’s physiological margin. It adds up with everything else one might be taking into the cockpit, such as dehydration, hypoglycemia, stress or lack of sleep,” Luchtman said.

The proper fit of the mask around the pilot’s face is also critical. As the pilot moves his head around there could be small leaks around the edge of the mask, which can impact the Onboard Oxygen Generating System’s (OBOGS) ability to provide the proper amount of air, he said.

During the squadron roadshows, a team of experts from the Aircrew Systems Program Office spot checks aviators’ flight gear and suggests how to get a better fit.

(U.S. Navy photos)

F/A-18E/F Mitigations

There are several efforts underway in the Super Hornet community: updates to the PE reporting guidance implemented in Fall 2019; introduction of the Hornet Health Assessment and Readiness Tool (HhART) to the fleet last year; and the ongoing installation of a digital pressure gauge, which will increase air crew awareness.

“We are in the process of replacing the analog pressure gauge with a digital pressure gauge that will record data and provide a digital readout of cabin altitude for the pilot. It will indicate whether or not the cabin altitude is on or off schedule or is too high or too low,” he said.

Modifications are underway and are expected to take 10 days to two weeks per aircraft.

One of the most effective mitigations to date is HhART, he said.

To reduce fluctuations within the aircraft’s Environmental Control System, the program office has developed a tool to identify sub performing parts before they fail.

The tool uses data collected via Slam Sticks worn by pilots during flight and evaluates how well parts are functioning. (For more on HhART, see article on page 17.)

“Since we instituted HhART, along with a couple of other changes, we’ve driven the rate down in F-18s significantly,” he said.

T-45 Goshawk Mitigations

All of the Navy’s T-45 Goshawks have been upgraded with the CRU-123 oxygen monitoring system, which checks the quality of air as it comes out the OBOGS concentrator to make sure it’s delivering the appropriate oxygen concentration. (U.S. Navy Photo by Liz Wolter)

Early in its investigation, the T-45 RCCA identified a primary contributing factor to oxygen-related PEs: low inlet pressure to the OBOGS concentrator, Luchtman said.

Program office engineers straightened the 90-degree bend in the inlet pipe and increased idle RPM on the engine.

“With the engine moving faster, it provides more air on the inlet side of the OBOGS concentrator. Those two things really eliminated the air-flow pressure issues with the OBOGS concentrator,” he said.

Another upgrade to the T-45 was the installation of the CRU-123 solid-state oxygen monitor in summer 2017.

“As the air comes out of the OBOGS concentrator, it passes through the monitor first. It’s a check on the quality of the air to make sure we’re delivering the appropriate oxygen concentration. If it’s incorrect, it gives the pilot a warning,” he said.

All T-45s have the CRU-123 and it’s working well, he added.

Physiological Monitors

“While the formal investigation has concluded, we are continuing to explore how we can optimize the human in the cockpit,” Luchtman said.

He is pushing for the development of physiological monitors that will show how the human is performing in real time, under temperature variances, under Gs, under pressure.

But he has learned that it is not as easy as it sounds.

“I’ve had to temper my enthusiasm because it takes a new approach to design sensors that will fit within the confines of the cockpit, survive the hostile environment and provide useable data,” he said.

Anything new must also be verified and validated before introduction to the fleet.

Despite the challenges, the Aircrew Systems Program Office is currently exploring five monitoring devices, which are in various stages of test, he said. 

The Navy is also working closely with the Air Force to identify a sensor for tactical aircraft that will not only provide useful data but will warn of an impending condition.

“We are depending on industry to help us develop and integrate the sensors into the cockpit, onto our flight gear and into our existing aircraft systems,” he said.

Way Forward

With the conclusion of the RCCA investigation, the functions of the PEAT will roll under the auspices of the Naval Safety Center at the end of April.

At that time, Luchtman is slated to take command of the Naval Safety Center to ensure continued flag oversight of physiological episodes.

“We are very thankful, not only to Naval Aviation leadership, but naval leadership as a whole and Congress for their support. There’s never been a question about resources when it comes to anything related to PE, and I do not see that changing.

“This remains Naval Aviation’s No. 1 safety priority and will continue to be until we’ve driven this rate down as low as we can.”

Andrea Watters is editor in chief of Naval Aviation News.  

Onboard Oxygen Generating System

Location of the T-6 Texan aircraft on-board oxygen generating system. U. S. Air Force photo by Lt. Col. Kyle

The Onboard Oxygen Generating System (OBOGS) was the first target of the root cause corrective action (RCCA) analysis process to understand physiological episodes (PEs).

“There was a lot of theory and discussion of contamination early on,” said Rear Adm. Fredrick Luchtman, Navy lead for the Physiological Episodes Action Team (PEAT).

“We took our OBOGS concentrators apart and put them through rigorous testing. We collected more than 21,000 samples of air and determined that the OBOGS air is extremely clean and not prone to contamination,” he said.

He attributes some of the early confusion to the fact that the OBOGS does not technically generate oxygen.

Ambient air is pulled into the system and passes through two sieve beds. The filters hold the oxygen and purge the nitrogen, then the system allows the concentrated oxygen to pass to the pilot.

“There’s no chemical process in which chemicals or contaminants could be introduced. The system doesn’t work in reverse and it cannot deliver anything less than 21 percent concentrated oxygen because that’s what’s in ambient air,” Luchtman said.

All Navy tactical aircraft, including the T-6 Texan, T-45 Goshawk, F/A-18E/F Super Hornet, EA-18G Growler and F-35C Lightning II, use OBOGS concentrators, and several replacement systems are in the works, he said.

The T-6 currently is flying with the 105 model and has begun taking delivery of the 106A Concentrator, which allows for some data recording, Luchtman said.

The T-45 currently flies with the GGU-7 and will upgrade to the GGU-25 concentrator beginning in second quarter fiscal 2022. The F-18 currently flies with the GGU-12, which will be upgraded in 2023 to a Life Support Systems Integration, which will provide scheduled delivery of a graduated amount of oxygen that increases as altitude increases. — Andrea Watters

Fleet Finds Unique F/A-18 Diagnostics Invaluable

The ultimate goal is to integrate the Hornet Health Assessment and Readiness Tool into the aircraft’s numerous complex systems to help improve supply, maintenance and readiness postures for F/A-18s and EA-18Gs. (U.S. Air Force photo by Staff Sgt. Matthew Lotz)

One year after first hitting the fleet, a unique F/A-18 analytical tool, Hornet Health Assessment and Readiness Tool (HhART), continues to benefit the warfighter and demonstrate how a mix of data analytics and engineering can serve as an accelerator for naval aircraft readiness.

“This cutting-edge technology will reduce unscheduled maintenance and make diagnostics and maintenance planning easier for the warfighter,” said Don Salamon, an engineer for the Physiological Episodes (PE) Integrated Product Team within the F/A-18 and EA-18G Program Office.

“While the inception of HhART stemmed from PE investigations, the resulting tool puts data to use in a practical, proactive way, directly supporting the ability to maintain increased aircraft readiness as well as maintenance and supply postures,” Salamon said.

HhART leverages aircraft and sensor data, maintenance information and advanced data analytics to create a health and performance dashboard display of the aircraft’s critical Environmental Control System (ECS). 

This information provides the fleet with enhanced prognostic and predictive capabilities to facilitate better troubleshooting and more efficient maintenance of this complex system of aircraft components. 

Naval Air Systems Command (NAVAIR) employed the tool and began surveilling the fleet in March 2019, providing squadrons with direct, proactive feedback and maintenance recommendations on flagged aircraft.

HhART became the top corrective action taken to combat PEs and after great initial success, the program rapidly expanded, leveraging data correlations and unique features identifying underperforming or failing systems ahead of the onboard aircraft prognostics, Salamon said.

He attributes its success to program office and NAVAIR leadership empowering and providing resource support to the multifaceted HhART Team, led by the PE IPT and comprised of data scientists and technical experts from NAVAIR, Naval Air Warfare Center Training Systems Division, Naval Sea Systems Command, the Carderock Division of the Naval Surface Warfare Center, the Center for Naval Analyses and The Boeing Company. 

“This cross-functional and collaborative effort between Industry and government highlights the Navy’s organic capabilities to execute true applications of ‘big data’ and produce actionable results and outcomes,” said Capt. Jason Denney, F/A-18 and EA-18G Program manager.

After a successful year in the fleet, the HhART team is transitioning this same methodology to other aircraft systems that are primed to benefit from similar data analysis, such as fuel systems, flight controls, propulsion systems and generator control units—the current number one degrader for both the F/A-18E/F Super Hornet and EA-18G  Growler.

The tool provides operators and maintainers with an indication of issues or degradation of systems in near real-time, enabling a more proactive approach and quicker identification of trends that often inform supply chain management decisions.

The ultimate goal for HhART is integration directly into the aircraft’s numerous complex systems, further supporting improved supply, maintenance and readiness postures for F/A-18s and EA-18Gs. The team behind it is currently digging into the data analysis and engineering challenges to bring that plan to fruition.

“The HhART Team has done an amazing job in creating this program and we expect, with its continued development and expansion to other aircraft systems, that it will become an indispensable tool for maintaining increased readiness for our aircraft platforms,” Denney said.

Written by Erin Mangum with the  F/A-18 and EA-18G Program Office.  

CMV-22B Ferry Flight Fuses Developmental, Operational Testing

The CMV-22B Osprey lands at NAS Patuxent River Feb. 2 after completing a ferry flight from Bell’s Military Aircraft Assembly & Delivery Center in Amarillo, Texas. U.S. Navy photo by Liz Mildenstein

The recent cross-country flight of the Navy’s new CMV-22B Carrier Onboard Delivery (COD) variant of the Osprey tilt-rotor aircraft was not only a milestone for the program, but also demonstrated the effective fusion of developmental and operational test in a real-world environment.

Over a two-day flight totaling just over 6.5 hours in the air, pilots Lt. Cmdr. Steve “Sanchez” Tschanz, Air Test and Evaluation Squadron (HX) 21, and Cmdr. Kristopher “Junk” Carter of Air Test and Evaluation Squadron (VX) 1, along with crew chief Naval Aircrewman (Mechanical) 1st Class Devon Heard flew the first CMV-22B from the Bell Military Aircraft Assembly & Delivery Center in Amarillo, Texas, to Naval Air Station (NAS) Patuxent River, Maryland, in early February.

The first flight of the aircraft outside of the manufacturer’s test area mirrored many of the conditions that the aircraft will encounter when operational.

“It was a great opportunity for operational and developmental testers to work together on the same flight,” said Tschanz.

Carter agreed with Tschanz’ assessment. “The biggest litmus test I have when we start out on operational tests is to find a mission that is representative of what we’re going to do with the aircraft once it is in the fleet,” Carter said. “With this flight, we got an early look at operational testing while we’re also doing developmental tests.”

“From a crew chief’s perspective, on this trip I was able to see both the developmental test side and the operational side integrated in one,” said Heard, who was a 2nd class at the time of the flight and has since been promoted.

The first Navy CMV-22 Carrier Onboard Delivery Variant of the V-22 Osprey flies above the Chesapeake Bay March 9. U.S. Navy photo by Erik Hildebrandt .

The role of developmental testing, which is the mission of HX-21, is to identify whether an aircraft or system meets the promised specifications. Operational testing, which is what VX-1 does, focuses on the ability of an aircraft or system to operate in the environments that it will encounter once it is deployed to the fleet.

Prior to the flight, Tschanz, Heard, Bell test pilot Andrew Bankston, and Naval Air Crewman (Mechanical) 2nd Class Trenton Olsheski conducted a series of developmental test flights to ensure the aircraft met its specifications. Following those test flights, it was time to deliver the aircraft to NAS Patuxent River.

Or, more accurately, almost time—the crew ended up waiting nearly a week for the weather to open up between Texas and Maryland. Because the aircraft was fitted with extensive test equipment, the flight was limited to clear weather and daylight hours.

On Saturday, Feb. 1, the weather finally cooperated and Tschanz, Carter and Heard flew first to Millington, Tennessee, for a refueling stop before continuing on to Patuxent River. Having flown together before, the three men quickly fell into a routine: while Tschanz was flying the aircraft, for example, Carter would be busy monitoring communications and Heard kept his eye on the weather.

The first Navy CMV-22 Carrier Onboard Delivery Variant of the V-22 Osprey flies above the Chesapeake Bay March 9. U.S. Navy photo by Erik Hildebrandt .

The Osprey’s high-visibility paint scheme, which the Navy uses to help make it easier to identify noncombatant aircraft, was part of the attraction when the aircraft landed in Millington, where the Naval Support Activity Mid-South base is located.

“There’s usually a certain amount of interest when a unique aircraft flies into any airport where that type normally doesn’t operate,” Tschanz said. “But in this case it was even more fun because we landed and people said, ‘Oh, that’s a V-22,’ and then immediately you can see the gears start turning in their heads as they start to realize that something is different about it.”

After refueling, the crew departed in the afternoon, expecting to arrive at Patuxent River in the late afternoon. But approximately nine-tenths of the way home, the weather started closing in over their destination, and the crew diverted to Lynchburg, Virginia, to wait out the rain overnight. And like in Millington, Tschanz, Carter, and Heard found themselves instant celebrities as pilots and aviation enthusiasts descended on them to ask questions about their unique Osprey.

The following morning, Tschanz, Carter, and Heard flew through clear skies to land at NAS Patuxent River, bringing a successful close to the aircraft’s first cross-country flight.

“We have a lot of tests to do before we know everything about the airplane, but this initial look was great,” Carter said of the flight.

“There was a lot of excitement, eagerness and anxiousness to be able to fly the first CMV-22B back to HX-21,” Heard said. “Now we own it and we’re ready to move forward.”

Written by Paul Lagasse, Naval Test Wing Atlantic Communications

VX-20 Sunsets Its C-2A Greyhound

U.S. Navy photo by Erik Hildebrandt

C-2A Greyhound BuNo 162142 made its final flight March 19 after 27 years with Air Test and Evaluation Squadron (VX) 20. The Navy is retiring the C-2A from the carrier onboard delivery role which is being replaced by the CMV-22B Osprey. There are currently 33 C-2s in the fleet, operated by the “Providers” of Fleet Logistics Support Squadron (VRC) 30 located at Naval Air Station North Island, California, and the “Rawhides” of VRC-40 at Naval Station Norfolk, Virginia. The CMV-22B is expected to reach full operational capability in 2023 and replace the C-2A by 2024.  

U.S. Naval Test Pilot School Celebrates Its Diamond Jubilee

When Navy Cmdr. Sydney S. Sherby received orders in March 1945 to assume command of a brand-new Flight Test Training Program at Naval Air Station (NAS) Patuxent River, he might not have guessed that 75 years later the program would grow into one of the world’s premier flight test institutions.

Today, the U.S. Naval Test Pilot School (USNTPS) graduates more pilots, flight officers and engineers each year than the other three major domestic and international flight test schools combined and has supplied nearly 100 astronauts to the American space program. But he probably would not have been surprised.

Sherby, a naval flight instructor with a degree in aeronautical engineering from the Massachusetts Institute of Technology, had reported to NAS Patuxent River as chief project engineer the previous year. Almost immediately, the base’s commander handed Sherby a tough assignment: develop an understanding of how the Navy conducted flight test and how it could do it better.

During World War II, the Navy had consolidated its units for flight test, radio systems, armament and experimental aircraft at NAS Patuxent River. Sherby suggested the Navy take advantage of that consolidation by establishing a formal program of education for test pilots and engineers who would then go on to staff those units.

Cmdr. C.E. Giese, the base’s flight test officer, agreed with Sherby’s recommendation and tasked him with drafting a plan for the future flight test school—in just seven days. With the help of two other officers, Sherby developed the school’s first curriculum, which covered aerodynamic fundamentals and procedures for testing aircraft performance and assessing aircraft stability and control, plus a roster of necessary air and ground tests and a standardized reporting form. The proposed 10-week course involved 37 hours of classroom work and nine hours of flying over the course of three days a week.

Less than two weeks later, Sherby and his sole flight instructor, Lt. H.E. McNeely, welcomed the first group of 14 pilots and engineers—retroactively dubbed Class 0a—to the USNTPS’ first semester, during which the test pilots under instruction flew a motley assortment of fighters, bombers and trainers borrowed from the base’s flight test unit. At the end of May, each of the graduates received a diploma and a slide rule.

Another key figure in the school’s early history, Capt. Frederick M. Trapnell, arrived at Pax River to assume command of the Naval Air Test Center in 1946. Trapnell, a former flight test officer who had flown fighters from the Navy’s giant dirigible airships in the 1930s, attended Sherby’s classes and quickly recognized the program’s need for additional funding and resources. He recommended sufficient resources be allocated to establish a full-time course for about 30 students, with classes convening every nine months. Trapnell got his wish, and the school soon went into business full-time. NAS Patuxent River’s airfield is named Trapnell Field in his honor.

Written by Paul Lagasse, U.S. Naval Test Pilot School Communications.  

1) Between 1958 and 1975, the F8U/F-8 Crusader supersonic air superiority fighter provided students with experience testing high-speed flying and maneuvering characteristics (U.S. Navy photo). 2) A Grumman F6F Hellcat, which students flew for test evaluation during World War II, in flight near Naval Air Station (NAS) Patuxent River, Md., 1944. ( U.S.Navy photo) .3) The Chance Vought F4U Corsair was at USNTPS from 1949 to 1952. (U.S. Navy photo.) 4) An aerial view of NAS Patuxent River with an F9F Panther, circa 1950s. (U.S. Navy  photo) 5) Douglas A-4D Skyhawk single-seat fighters were used for flight training from 1963 to 1994. (U.S. Navy  photo). 6) The backbone of jet flight training at USNTPS, the two-seat T-38 Talon, has been flying in its A, B and C variants since 1969. The school currently has 10 T-38Cs. (U.S. Navy  photo). 7) USNTPS has been flying the F/A-18 Hornet since 1984. Today, four F/A-18F Super Hornets are flown as part of the airborne systems syllabus for radar and weapons delivery evaluation. U.S. (U.S. Navy  photo).  8) Established in 1961, the military rotary syllabus is the only one of its kind in the U.S. and serves as the Army’s test pilot school. Here, a student and instructor conduct a preflight inspection of an OH-58 Kiowa. U.S. (U.S. Navy  photo).

U.S. Naval Test Pilot School Training Test Pilots of the Jet and Space Ages

In 1957, the flight test school formally changed its name to the U.S. Naval Test Pilot School. That same year, Marine Corps Maj. John Glenn Jr. (Class 12) set a new coast-to-coast speed record at an average of 725.55 miles per hour flying an F8U-1P Crusader fighter, and the Soviet Union launched the first artificial satellite, Sputnik 1.

The Jet Age reached a peak, and the Space Age had begun—and USNTPS was there to make sure that the nation’s flight test pilots, flight officers and engineers were ready for both.

In the 1950s, the depth and breadth of the curriculum expanded to include jet performance, irreversible flight controls and armament and electronic testing. In 1958, the school extended the course of instruction to eight months. And when NASA announced its seven Mercury astronauts in 1959, USNTPS was very well represented with four alums on the roster: Alan Shepard, John Glenn, Scott Carpenter and Wally Schirra.

The early 1960s saw the first major additions to USNTPS’ curriculum with the creation of a separate syllabus for rotary-wing instruction, an introduction to vertical takeoff and landing techniques and a soaring program.

USNTPS also saw its first Army graduate, Capt. John Foster (Class 28). During this time, the school also published its first manuals for helicopter performance testing and rotary flying qualities.

Today, the school’s rotary syllabus for military pilots is the only one of its kind in the U.S., and for this reason serves as the Army’s test pilot school.

The end of the decade saw an entire Apollo mission crewed by USNTPS graduates when Apollo 12 took Pete Conrad (Class 20), Richard Gordon (Class 18) and Alan Bean (Class 26) to the moon in November 1969.

Advances in computer technology had an impact on training at USNTPS beginning in the 1970s with the introduction of aircraft capable of variable stability including the Calspan Learjet, which remains a cornerstone of flight training at the school today. Advancements in technology during that decade required the school to expand its curriculum again to incorporate airborne systems and to lengthen the syllabus from eight months to the current 11 months, which the school deemed sufficient to allow more flight opportunities and time to absorb class instruction and apply it in the air.

In 1983, the USNTPS family proudly received the Navy Unit Commendation for “extraordinary standards of excellence in safety, maintenance, curriculum advancement, and overall multi-nation test pilot training”—a citation that would have undoubtedly pleased Sherby. That same year, Lt. Colleen Nevius (Class 83) became the first female aviator to complete training at USNTPS.

The fall of the Soviet Union provided a unique opportunity for USNTPS technical collaboration when the Gromov Flight Research Institute near Moscow—Russia’s equivalent of Edwards Air Force Base—hosted nine instructors and staff in the summer of 1994. USNTPS returned the favor a year later when it hosted a Russian delegation.

That same year, the doors of USNTPS’ new schoolhouse first opened to welcome its first classes of students after its official dedication the previous year. The decade also saw the inauguration of the Short Course Department, which offers two-week introductory courses to the developmental flight test community.

In 2003, the Short Course Department added an Unmanned Aerial Vehicle course and considered the unique test requirements associated with fielding such systems. As the Navy significantly increased its investment in unmanned aircraft systems (UAS) over the decade, USNTPS maintained its leading edge by incorporating unmanned test concepts into its syllabus for test pilots and engineers of the future.

In the 2010s, small UAS platforms such as the ScanEagle and MQ-8 Fire Scout gave way to larger UAS platforms like MQ-4C Triton and MQ-25 Stingray, and the establishment of the Navy’s first dedicated squadron to unmanned platforms—Air Test and Evaluation Squadron (UX) 24. UAS systems are increasingly being incorporated into the syllabus, culture and organization of USNTPS, today helping ensure students are up to speed on the growing field of unmanned aviation.

1) The Douglas F4D/F-6A Skyray jet fighter was in the school’s inventory from 1958 to 1969 (U.S. Navy photo). 2) USNTPS pilots flew the iconic Bell UH-1 Iroquois as part of the rotary-wing curriculum from 1963 to 1975 (U.S. Navy photo). 3) The school’s two X-26A Frigate gliders fly an average of 40 hours per year teaching students about high lift-and-drag evaluations, unpowered flying qualities and even aerobatics (U.S. Navy photo). 4) The variable-stability Learjet Model 24, developed by Calspan, appeared at USNTPS for the first time in mid-1981 (U.S. Navy photo). 5) USNTPS students flew the North American T-2 Buckeye trainer from 1972 to 2007. Today, one of these aircraft is preserved on the school grounds (U.S. Navy photo). 6) The T-38C Talon is USNTPS’ primary fixed-wing trainer; the school’s 10 aircraft fly a combined average total of 1,100 hours per year (U.S. Navy photo). 7) The USNTPS 11-month curriculum includes 530 hours of academic instruction in fixed-wing, rotary-wing and airborne/unmanned systems (U.S. Navy photo). 8) The school operates two U-6A Beavers as part of the Qualitative Evaluation program, which exposes students to the handling characteristics of a wide variety of unique aircraft (U.S. Navy photo by Erik Hildebrandt). 9) An early-model F/A-18 Hornet taxies at NAS Patuxent River. U.S. (Navy photo).

As another decade dawns, USNTPS continues to evolve its curriculum to ensure graduates are capable of confronting the technical and programmatic challenges of the Naval Aviation Enterprise of today and tomorrow.

Today, USNTPS proudly provides instruction to Navy, Marine Corps, Army and Air Force aviators, in addition to aviators and engineers from 17 partner nations, and civil service engineers across Naval Air Systems Command. The school accepts around 36 students at a time and runs two courses of 11 months each year. Its fleet of 44 fixed-wing, rotary-wing and unmanned aircraft is the most diverse in the Navy, encompassing 14 different type/model/series.

As it has since Sherby’s time, USNTPS continues to innovate in order to maintain its status as one of the world’s pre-eminent flight test educational institutions, dedicated to providing cutting-edge educational and flying opportunities.

Sources: United States Naval Test Pilot School Narrative History and Class Information, 1945 to 1982 and 1992 supplement; United States Naval Test Pilot School: 75 Years and Counting, 1945 to 2020

Global Sustainment Vision Overhauls I-level Maintenance Training by Standardizing ASM

Global Sustainment Vision and Commander, Fleet Readiness Centers (COMFRC) have standardized intermediate level (I-level) maintenance qualification, certification and licensing (Q/C/L) processes within the Advanced Skills Management (ASM) system.

Qualifications for Sailors are now recognized across all Fleet Readiness Centers (FRCs), detachments and Aircraft Intermediate Maintenance Departments (AIMDs) ashore and afloat, eliminating the need for remediation with a change in duty station and enabling quicker delivery of maintenance, repair and overhaul services to the fleet.

ASM was first introduced to the FRCs and detachments in 2010, followed by the AIMDs. The system changed the qualification, certification and licensing processes for I-level maintainers. It provided real-time access to training records that are critical for assigning qualified personnel to repair and maintain aircraft.

“ASM changed the way business was done. It gave us the ability to see the current qualifications of a Sailor in real-time allowing them to get to work more quickly,” said Mike Walter, the standardization team lead for the Global Sustainment Vision program.

Prior to the recent standardization, each individual unit was responsible for the development and upkeep of all qualifications. The unintended consequence of this was the need to retrain military maintainers due to variations in naming and methodologies between similar units. ASM couldn’t translate the variances and there was no central authority controlling the naming and descriptions of each Q/C/L. 

During Aviation Electronics Technician 2nd Class (AT2) Logan Watts’ first change of command, he lost two of his qualifications.

“It took me two to three months at my second command to get back up to speed. I thought a lot of that training was repetitious,” Watts said.

The Global Sustainment Vision team recognized the need for maintainers to be able to transfer their qualifications from one site to another and made ASM standardization a priority.

Aviation Electronics Technician 2nd class (AT2) Logan Watts, left, setting up calibration for De-Ice Test set at Fleet Readiness Center West (FRCW) DET Fallon, Nev. Right, Aviation Ordnanceman 2nd class (AO2) Ian Courtney and AO2 Tristan Rice complete a ready for issue inspection and move a SUU-79B/A to K-pool for issue. U.S. Navy photos by AZ2 Frederick Klink
AD2 Adam Sack, left, performs oil analysis checks on the spectrometer. Center, Aviation Machinist’s Mate Airman, (ADAN) Juvonni Headd disassembles a LAU-17F/A for inspection at FRCW DET Fallon. AT2 Zachary Smith, right, performs calibration checks on a De-Ice Test set. U.S. Navy photos by AZ2 Frederick Klink

“The first wave migrated 20 percent of Q/C/Ls into similar and already active Q/C/Ls. Another 20 percent were deleted because they were unnecessary,” Walter said. “We went on to review the remaining 60 percent and found more work could be done.”

By standardizing the requirements for certain qualifications the team was able to delete 40 percent of the listed requirements because they were repetitive. All qualifications are now under the sole control and responsibility of the I-level model manager at COMFRC and the fleet administrators at each site to maintain consistency and standardization moving forward.

A reduction in time required to requalify translates to an increase in time on task which can directly increase readiness.

Watts changed commands again in February, checking in at the Fleet Readiness Center West detachment in Fallon, Nevada. The ASM standardization allowed him to start work right away.

“I’m already set to take my exams for Collateral Duty Inspector. All I needed this time was a little on-the-job training,” he said.

“With this standardization initiative completed, Sailors and Marines reporting to a new I-level unit with previously held qualifications will have those reinstated. Removing the variance of training processes between units will have an average 90-percent reduction in time required to requalify,” Walter said.

“While we’re not done yet, I am encouraged by the improvements people are already seeing. When this is complete, it’ll be a game changer.”

Written by Kaitlin Wicker, a communications specialist for the Global Sustainment Vision. 

New Name, Same Commitment:
Global Sustainment Vision

To better align its focus with the Naval Sustainment System-Aviation (NSS-A), the Sustainment Vision 2020 program is now called the Global Sustainment Vision.

Global Sustainment Vision continues the program’s reforms at the Fleet Readiness Centers, engineering and maintenance, organizational-level and surge areas to complement NSS-A initiatives.

“The program has not changed its mission nor its focus, only its name. Our teams are still creating products and processes to equip military members and civilians to sustain Naval Aviation readiness,” said Keith Johnson, Global Sustainment Vision director.

“NSS-A really brought to light much of what we were already working on. It was great to have another program come alongside us and say, ‘yes, we need to fix this system,’” Johnson said.

In addition to the efforts spearheaded by NSS-A, Global Sustainment Vision continues refining and improving initiatives such as the Aircraft on Ground Cell and Maintenance Operations Center, total resource visibility, the capacity model, a web-enabled capabilities database, depot-level certification of military personnel, standardization of the Advanced Skills Management software, training gap closure, readiness modeling and parts forecasting, and logistics and engineering sustainment.

Each of these threads is interwoven with those of NSS-A to fill the seams and produce sustained readiness for Naval Aviation.

—Kaitlin Wicker  

Grampaw Pettibone

Gramps from Yesteryear:

September-October 2000

Illustration by Ted Wilbur

Lava Lament

A CH-53D Sea Stallion with a full load of troops on board was conducting insertion missions from an Army airfield to a landing zone in a lava field 6,560 feet above mean sea level. The pilot and copilot conducted hover power checks before departing the airfield. Winds at departure were 300 degrees at 10 knots, gusting to 15. The helo proceeded to the landing zone, dropped off the troops, returned to the airfield, took on another load and returned to the lava field.

On final approach, the copilot, who was at the controls, began a descent rate to establish the aircraft on glide slope for landing. Both the pilot and copilot were unaware they were experiencing a tailwind. The copilot slid the Sea Stallion to the left to avoid ground support vehicles located along the approach path.

The combined effects of being slow, with a tailwind, in an environment of high density altitude, and in a high gross weight configuration, placed the CH-53D in a hover-out-of-ground effect situation without sufficient power. The induced rate of descent exacerbated the situation, and the CH-53D began dropping to the ground uncontrollably. This is sometimes called “settling without power.”

Realizing the severity of the helo’s condition, the pilot (aircraft commander) pushed both speed control levers full forward in an attempt to increase power. The crew chief called for power and the aerial observer called for a waveoff. The collective was already at its upper limits as the pilot took over the controls. He tried to regain control by pushing the nose over and lowered the collective to execute a waveoff.

Instead, the helo struck the lava field short of the landing zone with little forward airspeed or vertical velocity. The tail rotor and left main mount struck lava rock. Simultaneously, the tail skid lodged in the lava rock causing it to fail aft. The tail rotor blades disintegrated on impact. The tail pylon separated from the aircraft, which then lifted 10 feet off the ground and began rotating counterclockwise.

The Sea Stallion struck the ground a second time and rolled nearly inverted. The engines continued to drive the main gear box and rotor head throughout the sequence, arcing the fuselage around until all the blades were completely sheared off from the rotor head.

Fortunately, this helo was equipped with three-point-restraint troop seats, and vertical deceleration forces were not sufficient to dislodge the seats. As a result, none of the crew and passengers sustained serious injuries.

Grampaw Pettibone says …

What a carousel ride that musta been! I’ll bet more than one heart leapt from chest to throat during that spin-around atop the lava field. The helo was flying at 30 to 40 knots at 100 feet above the ground on the approach. These numbers are consistent with a Sea Stallion when its hitting its Naval Air Training and Operating Procedures Standardization-prescribed parameters. Technically, it was the aerodynamic limitation imposed by the tailwind that did in the CH-53D. The pilots failed to determine the wind direction. Had they done so, they could have adjusted approach direction and stayed within the proper flight envelope. Situational awareness went by the board at a perilous moment.

Team Solves CH-53K Engine Integration Issues

Colored oil smoke indicates rotor wake and wind effects while external “tufts” adhere to the outside of the CH-53K King Stallion showing surface airflow during testing, which validated a modification mitigating exhaust gas re-ingestion.  (U.S. Navy photo)     

Industry and government engineers have mitigated an ongoing engine integration issue for the CH-53K King Stallion—the Marine Corps new heavy-lift helicopter.

This “tiger team” of experts from a variety of engineering backgrounds came together to find and optimize aircraft modifications using state-of-the-art computational modeling methodologies, risk management, flight test data and systems engineering tools.

“Bringing together the tiger team exemplifies the importance and purpose of an integrated test team,” said Col. Jack Perrin, program manager, Heavy Lift Helicopter Program Office. “It was great to see the team turn the corner for the program and produce a resolution to an ongoing problem. This was a priority for the Naval Air Systems Command, industry and the Marine Corps, and the team hit it out of the park.”

The program office oversees both the CH-53E Super Stallion, which is currently in use by the Marine Corps, and the CH-53K.

The CH-53K is the premier heavy-lift helicopter that will expand the fleet’s ability to move more material more rapidly. That power comes from three new General Electric T-408 engines, which are more powerful and more fuel-efficient than the T-64 engines currently outfitted on the CH-53E.

According to Debbie Cleavenger, assistant program manager for engineering and the program office’s chief engineer, three engines created several integration issues, including the most troublesome—exhaust gas re-ingestion (EGR).

“EGR occurs when the hot engine gasses are ingested back into the system,” Cleavenger said. “It can cause anything from increased life-cycle costs, poor engine performance and degradation, time-on-wing decreases, engine overheating and even engine stalls.”

Since April 2019, the tiger team completed more than 30 test events and evaluated 135 potential design solutions for engine integration.

“The systems constraints were significant,” Cleavenger said. “One change impacted multiple systems.”

Team members worked different root cause analyses in parallel, determining the cause and developing design models to mitigate causes for EGR. From those models, iterative flight testing resulted in a validated model to assess the most promising answer.

That model was then used to construct components for one of the test aircraft that flew a rigorous series of test flights to collect data to validate the model. The extensive set of flight test data was then condensed, analyzed and presented in December 2019 to show that the result performed as predicted and provided an overall design modification that would meet the needs for the CH-53K fleet aircraft.

All CH-53Ks built for the fleet will incorporate this production solution. Only one test aircraft has been modified to the production solution, since it would not be cost-effective or beneficial to the program to modify them all.

“This is exactly what an integrated test team is supposed to do,” Perrin said. “Bring their expertise to a project, look for resolutions in a dynamic and collaborative environment, determine the best path forward and keep this aircraft on track to the fleet.”

EGR testing was executed within the reprogrammed CH-53K program execution timeline to support Initial Operational Capability in 2021. The CH-53K is continuing toward completion of developmental test, leading to Initial Operational Test and Evaluation in 2021, followed by first fleet deployment in 2023/2024.

Victoria Falcon provides strategic communications for the Heavy Lift Helicopter Program.

CH-53K Logistics Demo Improves Maintenance for Fleet

Marines with Marine Operational Test & Evaluation Squadron (VMX) 1 load the main gearbox of the CH-53K King Stallion onto the aircraft aboard Marine Corps Air Station New River, N.C., as part of a Logistics Demonstration. (U.S. Marine Corps photo by Cpl. Ethan Pumphret)

Data collected during a recent Logistics Demonstration (LogDemo) for the CH-53K King Stallion heavy-lift helicopter is already paying dividends as the aircraft moves closer to fleet introduction for Operational Test and Evaluation in 2021.

Maintenance data collection and analysis is an ongoing part of the King Stallion program, but the LogDemo was a unique opportunity to put the CH-53K through its paces in test and development, while giving fleet personnel touch-time on the aircraft. Marine Corps participation in evaluating the integrated product support (IPS) elements is key to future readiness.

During the past 15 months, the CH-53K Supportability Test and Evaluation (ST&E) team, including industry and government partners, conducted the LogDemo with the Marine Operational Test and Evaluation Squadron (VMX) 1 maintainers at Marine Corps Air Station New River, North Carolina. The team completed more than 3,500 hours of ground test events.

“Although the window for performance is considered complete for LogDemo, we are still making opportunities to evaluate maintenance for data collection,” said Todd Winstead, CH-53K ST&E LogDemo lead.

The LogDemo kicked off an on-going process of observation, identification and analysis in the logistics process for the CH-53K, he added.

“LogDemo has helped us in early discovery of maintenance deficiencies, providing lead-time for improving product support prior to commencing operational test,” he said. “It will also increase efficiency for aircraft availability.”

“In LogDemo, we took an actual CH-53K aircraft apart and rebuilt it, documenting the process every step of the way,” said Lt. Col. Julian Rosemond, CH-53K product support lead. “The LogDemo gave our Marines advanced practical experience and improved problem-solving skills. They were able to obtain qualifications and improve their capability to perform function tests to be prepared for squadron stand-up.”

LogDemo was a win-win for all involved, he said. The team received real-time assessments by working with fleet Marines. The entire program gathered valuable data to correct and improve logistics support products that will lead to increased efficiency and accuracy in the performance of future maintenance operations.

A key to the LogDemo is the verification of data in the Interactive Electronic Technical Manual (IETM) modules using an iterative approach. The IETM is a digital manual that contains technical procedures that guide the maintainers in accurately removing and installing components; performing troubleshooting and functional tests; identifying replacement parts; and interfacing peculiar support equipment to perform tasks.

The team evaluated critical maintenance tasks while conducting verification of IETM procedures—from the use of support equipment to the specific tools used to perform maintenance. For example, during the evaluation for removing and installing a major component, Marines identified discrepancies with IETMs and steps missing to adequately perform torqueing and measuring for installing a main rotor head, thus requiring technical/engineering support to correct procedures.

“If not for LogDemo and the discovery of the improper procedures, serious damage or failure to a critical safe-for-flight component could have occurred,” Winstead said.

However, because of LogDemo, that risk was avoided and the documentation has been corrected, he said.

Though the LogDemo is now complete, the team’s work continues in providing deficiency reports and report summaries. The team is also preparing for future testing, including the CH-53K sea trials, which will occur later this year.

Written by Victoria Falcon, who provides strategic communications for the Heavy Lift Helicopter Program.

The Flagship Publication of Naval Aviation