News | Sept. 7, 2023

FRCE Engine Inspection Training Key to Aircraft Safety

Training developed and conducted at Fleet Readiness Center East (FRCE) has made a real-world impact on flight line readiness. The training provides the Marine Corps with the capabilities to bolster the number of mission-capable AV-8B Harriers while ensuring aircraft safety, and is now being applied to next-generation aircraft including the F-35 Lightning II.

The AV-8B Remote Visual Inspection (RVI) program trains and certifies Marines maintaining the AV-8B Harrier to successfully perform digital borescope processes on the Harrier’s F402 engine using RVI borescope equipment. These borescopes allow for the inspection of components in remote, hard-to-reach areas, such as the inside of an aircraft engine.

Since kicking off in 2015, the AV-8B RVI program has trained and graduated a total of 315 personnel including Marines, civilian aircraft maintainers and engineers.

“The skills demonstrated by program graduates are credited with successfully facilitating more than 60 on-wing repair and recoveries, which negated the need to remove the engine and increased mission readiness by reducing turnaround time,” said Terry Gerber, the AV-8B RVI Program developer and manager who serves with AV-8B Fleet Support Team (FST) In-Service Engineering.

The AV-8B FST oversees the RVI training program at FRCE, which offers courses in which students can become certified as RVI technicians and progress to higher levels of certification such as inspectors. The most recent course offering is the F402 Remote Visual Inspection Technology Tier-6 Shadow Borescope Technology & Low Pressure Compressor Processes training course which launched in October of last year.

“I’ve been a part of the Harrier community for some time now,” said Chris Gosnell, the AV-8B FST propulsion team lead. “Looking at the caliber of training that this delivers, I think it’s something that any type, model or series of aircraft should have in place. It’s recognized in terms of the enhanced safety it brings to our program. It is sending highly trained Marines back to the fleet and adds incredible value and quality to the AV-8 community.”

Gerber said the training courses are just one element of the extensive AV-8B RVI program. In addition to developing a standardized training and certification program, the team created the standards and procedures used to guide the use of RVI borescopes and equipment in the fleet, developing a comprehensive RVI Standard Process Manual.

“This has been a massive undertaking,” Gerber said. “The FST worked with a range of entities to make this happen including the program office, elements throughout FRC East, Marine units, as well as the manufacturer and civilian contractors. The Center for Naval Aviation Technical Training, Naval Air Warfare Center Aircraft Division and Naval Air Technical Data and Engineering Service Command (NATEC) Detachment Cherry Point played a big role as well.

“Championing and achieving an enterprise-wide change in mindset and technical processes is never easy,” he said. “You certainly can’t do it alone.”

This immense effort centered on the proper use of the borescope, a fairly small tool used to look for even smaller traces of damage. Gerber said RVI borescopes are utilized by technicians and inspectors at the organizational, intermediate and depot maintenance levels. The devices are particularly useful in inspecting damage caused by foreign objects and debris.

Borescopes can significantly improve serviceability assessments which determine if an engine needs repair as well as the level of necessary repair. Borescopes help units maintain combat readiness by expediting the return to service of engine assets, but only if used correctly.

Carl Irvin, an F402 engine equipment specialist supervisor with NATEC Detachment Cherry Point, serves as the lead examiner for the RVI training. He has worked with the Harrier for nearly four decades and is no stranger to using a borescope.

Irvin said borescope measurements can be impacted by a wide range of factors such as the distance or angle of engine blades from the borescope. If procedures and processes differ from unit to unit, this could lead to different interpretations of borescope imagery.

“If the damage you were looking at is actually larger than what you thought, it impacts the safety of the engine and the aircraft,” Irvin said. “If the damage is actually smaller than you thought it was, you’ll be pulling an engine for no reason.”

Pulling an engine from service due to an incorrect borescope reading has impacts on a unit’s flight line readiness. The AV-8B RVI program tackled this issue by standardizing the entire process and creating an RVI Standard Process Manual that encompassed all procedures, from start to finish, for performing effective RVI inspection of the Harrier’s F402 engine.

Gerber described the process as challenging, citing a lack of detailed manuals and instructional materials related to borescope inspection throughout the aviation world.

“We had to develop our RVI manual from scratch,” Gerber said. “There was not any equivalent fielded in the Department of Defense or the civilian sector that we could identify. We looked hard but none were found with the level of rigor and detail we were looking for. It had to be right. In the RVI business, the smallest of details have a profound influence on the ultimate outcome.”

Gerber described the development of the manual, as well as of the training regimen and technical data products now utilized in the program, as a collaborative process driven by interviews that FST engineers held with fleet maintainers and depot artisans, maintenance supervisors and leadership.

According to Irvin, the painstaking research and data analysis performed during the AV-8B RVI program’s development have resulted in comprehensive procedures and instructions now standardized across the Harrier enterprise.

“There is a lot of science involved in it now,” Irvin said. “The manual the FST has written tells you exactly how far the borescope is from that blade. There is a standard across the board and everybody involved knows what they’re looking at.”

In addition to creating the RVI training manual, Gerber said the team put a great deal of effort into developing training aids for the program. He describes the training as consisting of 20 percent academic instruction and 80 percent hands-on practical exercises. Training classrooms are equipped with actual F402 engines that students must inspect using the same borescopes and equipment that are now standardized in the fleet. He said the emphasis is on realism and the aim is to ensure the standardization of technical processes across the enterprise.

“The equipment used in our training environment is comprised of the exact instruments, equipment and tooling the inspector will be required to work with in the field,” Gerber said. “The only details we don’t include in our training environment are the noise, movement of the aircraft and the less than hospitable environmental conditions they might encounter in the field.”

In the past, Gerber said the qualification process to make serviceability assessments was very subjective and varied widely between units and activities. He said the institution of the AV-8B RVI training and certification program put into effect much needed qualification standards.

“Today, everyone operates from the same script, and everyone engaging in RVI inspection or serviceability assessment must follow the same processes,” Gerber said. “Each individual goes through the same rigorous, standardized training requirements before they can do the job. With this program, we’ve standardized not just the certification process, but all technical processes, procedures, equipment and policies across the Harrier enterprise.”

Since the introduction of standardized borescope inspection training and certification requirements, Gerber said the program has essentially eliminated disagreements between organizational, intermediate and depot maintenance levels in the identification and classification of serviceable versus unserviceable damage to the F402 engine.

Irvin credited these successes to the FST’s efforts in standing up the RVI program as well as the cooperation between the many organizations involved. He also cited the Marines who graduate from RVI training as a crucial factor in the program’s success.

“The FST did the hard work, they wrote the book,” Irvin said. “That was step one. The last part is with the warfighter. They come to learn and digest everything. Then they go put everything to use in the fleet and keep their pilots in the air.”

In addition to the five main RVI training courses offered at FRCE, there are wide range of additional training and support services on hand, ranging from basic borescope systems and RVI equipment familiarization to RVI equipment and technical procedure proof of concept vetting. To meet the specific needs of individual units, the program even offers borescope user training tailored to the unique needs of the customer.

The course offerings now extend beyond the realm of the Harrier’s F402 engine. Gerber said the team also supports the F-35 Lightning II by offering on-location basic borescope system and inspection skills development training for the aircraft’s F135 engine at five sites. At some point in the future, the program is investigating the feasibility of supporting additional courses for the F-35B Lightning II lift fan.

“We can take the lessons we’ve learned and everything we’ve built in support of the AV-8B and utilize it in support of aircraft like the F-35,” Gerber said. “The goal is to grow in scope and technical capability and pursue championed RVI training services for fifth and sixth generation aircraft propulsion systems and subsystems.”

Gerber said the RVI training team is currently pursuing endorsement and formal recondition by the American Society for Nondestructive Testing for the RVI training program. The team also has its sights set on earning endorsement as a Department of Defense Center of Excellence for Remote Visual Inspection Technology.