One of the many interesting exhibits at the 2013 Association of the United States Army (AUSA) Annual Meeting and Exposition was the “Abrams ‘Dieselization’ Project” highlighted by General Dynamics Land Systems (GDLS). Features of the company project range from a new diesel power package to the incorporation of a new track design.
The concept of placing a diesel engine in an Abrams would likely draw the interest of many historians who recall the early controversy surrounding the selection of a turbine engine for the original XM1 tank design.
While the turbine performance issues were subsequently resolved and the design combat proven on the battlefield, the new interest in a diesel option is supported by industry modeling of financial benefits.
Just one example of these early feelings can be found in a January 1980 report issued by the [then] U.S. General Accounting Office (GAO), in which the GAO Comptroller General raised a number of questions surrounding the early XM1 test program. At that point in time, production of the initial increment of 110 XM1s was already under way. However, in the GAO’s report to Congress the Comptroller General noted, “Serious doubts remain about the performance of the XM1’s turbine engine,” going on to question mean miles between failure in earlier operational and development testing and other mobility issues.
U.S. Army soldiers with Company D, 2nd Battalion, 8th Infantry Regiment, 2nd Brigade Combat Team, 4th Infantry Division, come on line in an M1A2 Abrams tank before moving on to assault an objective during breach training near Fort Carson’s Camp Red Devil, Colo., Jan. 10, 2012. General Dynamics Land Systems is looking to make up a series of upgrades to the Abrams fleet. U.S. Army photo by Staff Sgt. Andrew Porch
“Because of the uncertainty of the tank’s performance with the turbine engine, members of the Congress have suggested on several occasions that the Army develop a backup diesel engine,” the report stated. “If this were to be done, it would have to be tested in the same manner as the turbine. Switching to a diesel could possibly delay fielding the tank. However, if reliability and durability problems continue to plague the tank when operating with the turbine engine, the diesel would seem to offer the better alternative.”
While the turbine performance issues were subsequently resolved and the design combat proven on the battlefield, the new interest in a diesel option is supported by industry modeling of financial benefits.
“The reason we have the diesel engine displayed out here is that we came up with an initiative called ‘Formation Based Decision Making,’” said S. Michael (Mike) Cannon, senior vice president, ground combat systems, General Dynamics Land Systems.
Although the Army has yet to make any decision on a potential dieselization of Abrams, Cannon said that such an upgrade could be accomplished through one of the planned near term engineering change proposal (ECP) phases.
Outlining the Abrams Dieselization Project at AUSA, Cannon offered that the equipment in the three major U.S. Army combat formations – Infantry Brigade Combat Teams (IBCT); Stryker Brigade Combat Teams (SBCT); and Armored Brigade Combat Team (ABCT) – “should establish a baseline for what those formations cost you. And then, as you make equipping decisions in the future, you should make them with awareness of that baseline and whether you are going to make it a more expensive formation or a less expensive formation. So, rather than making your equipping decisions based on one single system, you can look at them based on the entire formation before you make the final decisions.”
Although the Army has yet to make any decision on a potential dieselization of Abrams, Cannon said that such an upgrade could be accomplished through one of the planned near term engineering change proposal (ECP) phases.
The current Abrams “diesel solution” offered by GDLS includes the Tognum America/12V883 diesel engine and new Diehl 570P3 track.
According to Michael Parks, senior project engineer at MTU Detroit Diesel, the new design reflects a number of advances in diesel technology over the past 35 years.
“Things like going from a mechanically controlled simple injected [fuel] spray to a high pressure common rail is, by far, the best improvement to diesel engines,” he explained. “We had some fuel injected systems back then, but nothing along the lines of common rail, where it’s extremely high pressure fuel being atomized in the cylinder rather than sprayed. With that, now you get extremely good control cylinder to cylinder, as well as the entire engine, for power, peak pressure, combustion, heat out the exhaust, and timing. You’ve got a lot more control of the engine.”
“Controls would probably be the next thing,” he added. “With the better ability to control that system you get a lot more power out of the engine.”
U.S. Army soldiers from Company C “Cyclones”, 1st Battalion, 64th Armor Regiment, 2nd Armored Brigade Combat Team, 3rd Infantry Division, try to get the quickest time completing a track removal and reinstallation on an M1A2 SEPV2 Abrams tank at their battalion’s motorpool, Fort Stewart, Ga., Sept. 10, 2013. General Dynamics Land Systems has also proposed incorporating a new track design, based on track used by the Leopard 2 tank. U.S. Army photo by Sgt. Richard Wrigley
Other advances cited included quieter operations and reduced pollutants.
The new Diehl 570P3 track design on the Abrams diesel concept is a modification of a Leopard 2 tank track with a larger center guide and different rubber pads.
Returning to the Formation Based Decision Making model, Cannon said, “We’ve done our homework. And this is gaining traction with TRADOC. They are actually thinking that they should start looking at it so that they don’t do harm to the formations by making individual decisions on individual pieces of equipment, but rather … go with a bigger, broader view.”