ANNISTON ARMY DEPOT, Anniston, Ala -- The Abrams M1 main battle tank is synonymous with Anniston Army Depot whereas the legacy combat vehicle has been overhauled, serviced and evaluated at the installation since 1980. The process of testing the Honeywell AGT1500 gas turbine engine that powers the M1 is completed by using the dynamometers located in the Directorate of Production’s turbine engine shop. The dynamometer creates resistance to test the performance and overall functionality of the engine. The first turbine engines tested at the depot took place in 1983. In 2010, updated dynamometers and control rooms were constructed, and turbine engine testing continued in its new home.
Heavy mobile equipment mechanics perform the necessary testing using test cells. The turbine engines are placed on a test stand in the test cells and remain there during pre-testing, testing, and troubleshooting. The mechanics follow the acceptance test procedure manual to perform the tests. This manual is produced by Honeywell Aerospace, the original equipment manufacturer of the AGT1500.
To enhance their knowledge of the AGT1500, they learn the process of disassembling and assembling the engine. This helps when troubleshooting potential engine issues found during the test phase. “The more you learn about the engine, the better you’ll understand how to troubleshoot one,” said Ysidro Morales, heavy mobile equipment mechanic and dynamometer operator.
Additionally, mechanics are offered the opportunity to take an annual AGT1500 Familiarization Course to remain educated on the turbine engine.
The dynamometer is operated from a control room using test measurement and diagnostic equipment. The test cells are on a six-month calibration schedule and TMDE comes in to calibrate everything in the test cell. This calibration process keeps the instrumentation within their specified limits. Over 100 parameters are followed in the test procedure which includes flows, pressures, temperature, and performance. Eighty-eight test instrumentations are used throughout the test procedure including vibration pick-ups, pressure probes, thermal couplers, and flowmeters.
Prior to beginning the test procedure, 24 serial and part numbers must be entered into the computer program. During the pre-test phase of the test procedure, the computer system asks a series of questions requiring the mechanic to enter data such as engine oil level, voltages, specific fuel gravity, temperature and current humidity.
In the event the mechanics must enter the test cell while the engine is in operation, safety is paramount. They must wear double ear protection, along with the standard personal protective equipment. The engine must be at 750 horsepower or below in order for a mechanic to enter and remain in the test cell.
A 10,000-gallon fuel tank holds the F24 jet fuel that supports all five test cells and water used during the test phase is recycled through a cooling system. The two systems are serviced by the Directorate of Public Works. All electrical issues involving the test cell and control room are serviced by the electrical shop. Any maintenance or repairs to the test cell, lubrication system reservoir, and the intake and exhaust system is performed by the millwrights. Morales spoke of the importance of multiple shops supporting one another. “When we’ve done everything we can do to troubleshoot the engine and test cell, then we contact them for support,” said Morales.
In the event of a fire, two FM200 fire suppression systems are located in the control room. If the temperature reaches 135 to 165 degree Fahrenheit in either the control room or the test cell, the system will initiate the fire alarms. If this occurred in error, then the mechanics have the ability to delay the system from releasing the chemical suppression agent.
For an engine that doesn’t require troubleshooting, testing takes about six hours. This time includes the engine arriving at the test cell until the time it leaves. The mechanics test approximately 30 to 50 turbine engines per month. All test data gathered is stored on a computer and sent to engineers at Honeywell Aerospace in Arizona.