U.S. soldiers inspect a UH-60 Black Hawk tail rotor after a flight in Afghanistan. (Sgt. Richard Wrigley / U.S. Army)
A new effort to capture and share research data across U.S. government agencies could help in fine-tuning the life expectancy of various Army weapons systems.
The collaboration, known as CBM Enterprise, is named for condition-based maintenance, a method of predicting and executing maintenance needs based on real usage as opposed to pre-ordained milestones.
Researchers from the Air Force, Office of Naval Research and the Federal Aviation Administration are sharing data with the Army Research Laboratory (ARL) in support of the lab’s CBM investigations.
As chief of the mechanics division within ARL’s Vehicle Technology Directorate, scientist Dy Le describes CBM in terms of an ordinary automobile’s scheduled oil change.
“We have been replacing or maintaining the equipment based on time or cycles or miles,” he said. A car gets its scheduled oil change at 3,000 miles, regardless of whether the oil is still fresh or expired. Weapons systems maintenance has likewise been run according to largely arbitrary schedules.
“On aircraft it’s the same thing. Every component on an aircraft is designed with a certain life span and when it reaches that point they will disassemble it and replace it, even if sometimes it is still good,” Le said.
That time-based program can lead to items being swapped out while still perfectly serviceable, while other items stay in service when they ought to have been replaced, thus causing safety hazards.
The research lab has been looking at CBM as a way to produce a maintenance plan based on real-world usage.
Take for instance the rotor shaft on an H-60 helicopter. A time-based maintenance schedule is simply unrealistic.
“That aircraft can be used for different purposes. It can be used to fly a troop transport mission or it can be used to lift heavy equipment. Those are two very different usages, one is severe and the other is not. Depending on the usage that shaft may last longer than the design life or it may last shorter,” Le said.
The details can get even more subtle. An aircraft making a 45-degree turn, for instance, suffers more stress than an aircraft flown more gently.
CBM seeks to record and analyze such fine points, tracking how hard and how fast an aircraft flies, then processing that information through complex algorithms to determine the likely expiration date of various parts.
Much of the technology exists already, albeit in various stages of maturity. Army researchers are looking to bring those capabilities up to their full potential, while integrating their outputs in order to get the greatest possible reading on when and how a weapons system will come due for maintenance.
“We are talking about making decisions that could have an impact on soldiers’ lives. If we make a wrong decision based on technology that is not fully mature or validated, the aircraft may crash,” Le said. “So we want to be 100 percent sure that the CBM solution is accurate.”