The Two-Man Tank: An Idea Whose Time Has Come

Introduction The tank has been the focal point of modem land warfare since its introduction on the battlefield at Cambrai in 1916. The lumbering machine gun platforms of WW I required a ten-man crew and had an operating radius of only a few miles. In WW 11, tank crews had been reduced to five men, and the reliability of the tanks had improved to the point that tactical thought now focused on their employment. Today’s modern tanks feature four-man crews, awesome firepower, improved mobility, and the most modem technology. Our current doctrine, the AirLand Battle, attempts to structure the battlefield so that an armor-heavy task force or brigade can strike deep into the enemy’s rear, disrupting his communications, his command and control and, ultimately, his timetable for success. Advances in technology have enabled tank developers to employ the most modern fire control and propulsion systems. Laser rangefinders, turbine engines, and integrated solid-state fire-control systems, packaged in a 60-ton body, have prompted some experts to predict that the tank has reached its developmental potential. The two most common reasons given for this prediction are the tank‘s high cost and its ever-growing logistics tail. Are these experts correct? Has the tank become so expensive as to make it an unaffordable luxury? No! Now, as never before, the time is right for another evolutionary change. Tanks must cost less, be smaller, and use the most reliable aspects of state-of-the-art technology. The next main battle tank needs to be a two-man tank that can, more cheaply and effectively, accomplish all of the aspects of any future doctrine. Current Design The trend in past tank design has been to develop a basic tank model, using the best existing technology, and then product-improve that basic model over time. But, as a report published in England points out, “With few exceptions, tank design has changed very little in the last 35 years. The basic concept consists of a turreted vehicle with the driver in a hull compartment and the remainder of the crew located in the turret.”l Even the M1 tank with its turbine engine, vastly improved suspension, and improved levels of protection, still has a four-man crew. Currently, all Western main battle tanks (MBT) feature four-man crews, and, not surprisingly, all have basically the same weaknesses. They are all big, expensive, and hard to handle when they must be transported out of the theater in which they are deployed. Advantages A two-man tank, on the other hand, possesses several distinct advantages over a four-man tank. These are: reduced size, reduced vulnerability, reduced costs, and improved strategic transportability. I will discuss each of these advantages in detail. Reduced Size The large size of current MBTs makes them relatively easy to detect and easy to hit, given the excellent accuracy of current antitank (AT) weapon systems, munitions so lethal that a tank that is detected and hit stands a very good chance of being destroyed. As a recent International Defense Review article notes, “The size of the present-day conventional tank turret makes it such an outstanding target for enemy identification and fire. In addition to being too high and too wide, turrets have also become too long, exposing large areas of only moderate armour protection to enemy flank attack.”* A two-man tank would reduce the overall size of the tank by moving the crew compartment from the turret into the hull. With the crew in the hull, the main gun, with an automatic loader, would be the only portion of the tank above the hull. This reduced crew compartment size would also reduce the volume of the tank that would have to be given maximum armor protection. Some people estimate that this configuration would not only reduce the size of the vehicle, but would also reduce thevehicle weight by at least 15 percent. This weight reduction would occur by eliminating the need for the bulky mass of armor that now protects the crew above the turret ring.3 The relocation of the crew into the hull assures that a reliable automatic loader can be developed for a 120-mm main gun. This is important because in the heat of battle a crew member will not be able to leave his protected compartment to clear a jammed autoloader or repair a broken part. A crew with an inop- 40 ARMOR: The Magazine of Mobile Warfare

This view - and the frontal vie following page - isof the Gemini 2-man tank, a British design study. erative autoloader will have to displace from their fighting position to a protected, relatively secure area where they can repair themal-function. The Army Tank Automotive Command (TACOM) is currently developing a tank test bed with an externally mounted 120- mm gun and with an automatic loader to validate the feasibility of such a y s t e m. The Swedish Army has fielded the S-Tank, a tank with a reliable automatic loader, but the gun is fixed in the hull rather than mounted in a rotating turret.5 The point of mentioning the S-tank is not toimply that the two-man tank should have a fixed gun mounted in the bull, but to demonstrate that the technology does already exist, in the Western world, to produce a reliable autoloader. Another advantage derived from an autoloader is loading speed. Although a man may beat an autoloader over a short time, he will slow down as fatigue sets in. The autoloader will keep loading rounds until the ammunition is expended. This fact has already been demonstrated in the S-Tank, according to an article in ARMOR Magazine: “The automatic loader of the S- Tank already gives a considerably higher rate of fire than that possible with manually-loaded guns and makes all 50 of its rounds ready to fire.”6 Redueed Vulnerability The second advantage of a two-man tank is its reduced vulnerability to enemy detection and to being hit. This is passive protection rather than active protection, but the net effect is decreased vulnerability. The two-man tank would employ hull defilade in defensive positions, as today’s tanks do. This concept allows the entire hull of the vehicle to be parked behind a hill or a berm, or in a dug-in fighting position. (As an article in Defense Week recently stated: “The concept is called ‘hull defilade.’ Army strategists say that a heavily armored hull with an elevated gun would be easier to conceal in trees and bushes, yet more survivable in the open battlefield.”7 The in-hull crew compartment provides increased levels of protection over the current in-turret crew compartments. Because there are fewer men to protect, comparable or increased levels of protection can be achieved at reduced cost over a tank with a four-man crew.8 It would also be possible to completely separate the crews from all main gun ammunition, thus decreasing the vulnerability of the crew and the tank to ammunition fires. With the crew in a separate compartment which has no rotating seals or holes for guns or ejection ports, NBC protection would be much simpler. Less power would be required to maintain an uncontaminated crew environment, making it easier to produce an overpressure protection system for the crew. The crew could be effectively sealed into their fighting compartment, protected from the dangers of ammunition fires and NBC contamination, and could realistically expect to fight the battle that way.9 Another advantage gained by reducing the overall size of the tank would be the ability to increase the armor protection to meet the threat of a future enemy “super-weapon.” It is generally agreed that current MBTs have reached the upper limit of armor growth potential, given current size, weight, and cost constraints.10 A smaller, less expensive, tank does not suffer those limitations. Its growth potential in armor protection, especially to top-attack munitions, is virtually unlimited.” Decreased Cost Today’s tanks possess capabilities unheard of 20 years ago. As cited in the Annual Report to Congress-Fiscal Year 1986, “The M1 tank’s superior agility, advanced fire control system, and modem armor will make it an effective and survivable counter to Soviet armored forces through the 1990s and beyond.”12 Ironically, the very capabilities which make modem tanks so formidable also threaten their very existence. High systems costs not only add to budget deficits but limit the number of tanks that can be produced. The United States plans to produce only 7,467 M l sand MlAls by the early 199Os.l3 One solution to increased cost isa smaller tank. A smaller tank with a two-man crew will cost less than the current M1 tank with a four-man crew. The most significant reduction in cost will be due to the reduced size of the crew. Only half the number of tank crewmen will have to be trained to man the tank fleet; or, looked at another way, you can crew twice as many tanks with two-man crews as you can with four-man crews. The savings will also embrace training costs, salary costs, medical costs,dependent support costs, and retirement costs. In this era of shrinking budgets and reduced manpower pools, these advantages become more and more significant.14 Smaller tanks would also reap cost-benefits in other areas. As mentioned above, a two-man tank ARMOR The Magazine of Mobile Warfare 41 would not only expose less surface area to the enemy, but would also reduce the crew compartment size. Both of these reductions would contribute significantly to the reduced cost of the tank. Since only the main gun and portions of the autoloader would be exposed above the level to the hull, less of the tank would have to be afforded the levels of protection that would ensure crew survival. International Defense Review had this to say about a tank with a hull-located crew: “If the opponent merely destroys a gun and autoloader, but the vehicle itself is still mobile and the crew is intact, then survivability takes on a different meaning.”’ Less area to protect means reduced armor costs and a lighter tank. Lower overall weight because of less armor will make it possible to use a smaller, less expensive, and more efficient engine to power the tank. Smaller engines reduce fuel consumption, thereby reducing the cost, not only of the fuel, but of the numbers of refueling vehicles that must be purchased. These reductions should require fewer personnel in the logistics train to refuel the fleet, but it is dangerous to extrapolate a cost saving on their account. Some of the personnel spaces saved in the fuel hauling arena may be necessary in the organizational maintenance arena. Strategic Transportability Strategic transportability is one facet of tank design that has been sacrificed in the current generation of MBTs. Tanks have become SO large and heavy, and they require so much support equipment, that strategic airlift for a tank battalion is almost out of the question. As the Fiscal Year 1986 budget states, “Heavier forces, such as armored and mechanized units, cannot be transported rapidly by air in the numbers needed for either a European or Southwest Asian conflict. It is simply too expensive to buy that large an airlift force.”’6 As the budget document goes on to explain: “Yet we must be able to move such units quickly, particularly in a NATO reinforcement, given the heavily armored forces they would face. Large armored and mechanized forces can be deployed rapidly only by combining airlift with extensive pre-positioning.”“ The pre-positioning discussed in the budget works only if the equipment happens to be located in the Sght theater. If not, then the strategic planners must make some critical decisions on priorities of air transport and the perceived need for armored vehicles early in the conflict. The C-17 aircraft is being developed to rectify this strategic airlift deficiency and to augment airlift capabilities within theaters. AS described in the budget document: “Though smaller than the C-5, the C-17 will be able to carry the full range of military equipment, including all armored vehicles and most other outsized cargo. Unlike most other intertheater aircraft, however, it will be able to operate on austere airfields, thereby increasing the amount of cargo that can be delivered directly to operating forces.’’18 Equipment that cannot be transported by air, or pre-positioned, must be shipped by sea. Even with the use of fast sealift, goals for the deployment of US.-based forces are challenging. For southwest Asia alone, the budget document states: “Our objective is to be able to deploy a major joint task force and required support within six weeks of being asked for assistance.”lg Even if the two-man tanks were unable to show a significant enough weight decrease over the current family of MBTs to make it a viable candidate to be airlifted, its weight and volume reduction could substantially reduce the fast sealift requirements. In addition, its lighter weight would make it easier to move across unimproved beaches. Equally as important, the vehicle’slighter weight would reduce the overall weight classification for any bridging needed during the employment of the two-man tank unit. A smaller, lighter, tank would greatly reduce the problems associated with stratepic transDortabi1- ity. Ideally, these two-man vehicles would meet the volume and weight constraints of a C-141, thus adding another dimension to strategic power projection. In any event, reduced weight would, in turn, reduce the number of sorties necessary to transport a tank battalion, and the reduced number of refueling vehicles would also reduce the size of the logistics support “tail” that would have to be deployed to support the battalion. Any significant reduction of the airlift requirements would greatly assist future planners in preparing for worldwide contingency missions and could eventually reduce the need for some of the pre-positioned stocks that are currently maintained overseas, and for fast sealift that would be included in future budget requests. Potential Problems As with any new concept, there are potential problems that could detract from the overall effectiveness of a two-man tank. Foremost among these is the reliability of the autoloader. Without a safe, reliable autoloader, the basic concept of the two-man tank is not feasible. As has already been stated, however, much research and development is taking place in that important area. Experts have written recently that “the message is very clear: autoloaders will be used, and it is more than likely that they will be incorporated in the next generation of main battle tanks.”20 Crewmen, although reduced in number, must be completely cross-trained in each other’s jobs. The two crew stations would have identical controls to enable each crewman to fight and drive the tank from his position in the hull. The crewmen’s level of technical expertise will have to be increased. This increase in training is to be expected since the two men will now be performing all of the tasks that are currently those of a four-man crew.21 Crew maintenance duties, especially hull maintenance and repair will have to be closely examined to ensure that all of the tasks that a crew will have to perform are within the physical capabilities of a two-man crew. The heavy components of a tank hull must either be assembled in small manageable sections (like the side skirts on the 42 ARMOR The Magazine of Mobile Warfare

Ml), or the crew must be given special tools, winches, or jacks, to allow them to perform the necessary heavy maintenance. Much thought must also be given to developing more reliable components to reduce the need for crew replacement of critical parts.22 Consideration should also be given to revising the maintenance allocation charts to direct that some of the heavier tasks be performed at organization level rather than at crew level. A two-man crew’s ability to acquire targets would be degraded as four eyeballs cannot be expected to perform as well as eight. Certain technological advances must be incorporated into a two-man tank that normally might not be placed in a four-man tank. A panoramic, stabilized camera must be mounted on the turret roof to ensure 360- degree vision for both crewmen. This will necessitate two television viewing screens, but they can be electronically linked to the thermal sights to improve the thermal viewing capability.23 These electronic aids would assist the two man crew in target acquisition and identification and in some measure make up for the loss of two sets of eyeballs. Revised doctrine for the tactical employment of the two-man tanks could also aid in overcoming the degradation of target acquisition. Two-man tanks could be employed as mutually supporting two-tank sections. These sections, after appropriate section training, would then have the equivalent number of eyeballs as one four-man tank, but would possess twice the firepower. Conclusion As a recent article in Defense and Foreign Affairs notes: “There is nothing which dictates that an MBT must be large and heavy; what is important is that it be a survivable system capabIe of delivering mobile, effective, firepower on the battlefield.”24 The next MBT must possess reduced vulnerability, increased protection, and improved strategic transportability. In addition, current budgeting trends indicate that it should cost substantially less than current tanks. A two-man tank not only fulfills all of the requirements for the next generation tank, but it does so with the real promise of a true reduction in costs - not only the costs associated with the production and fielding of the vehicle - but those associated with the highly trained force that would man the vehicle. If we are to continue to field an elite tank force, capable of deploying anywhere in the world to support the national strategy, then the next MBT developed for our forces must be a two-man tank. Footnotes 7Duffy, Michael. “Turn-of-Century Tank Might Have Smaller Crew, No Turret.” Defense Week, January 23, 1984, p. 3. 8Fletcher, Robin, op cit., p. 50. g“Gemini - A Two Man Tank for NATO,” 19Ibid, p. 196. ZOJenkins, D. H. C., op cit., p. 908. 21“Gemini - A Two Man Tank for NATO,” 221bid, p. 12-1. 231bid, p. 10-2. ‘“Gemini - A Two Man Tank for NATO.” Project Report - 28 Long Armour Infantry Course, Amour School: Bovington Camp, Dorset, England. 1977, p. 1-1. ZFletcher, Robin. “From Tank to Overhead op cit, p. 11-4. Gun.” International Defense Review. Vol. 17, ‘OBackofen, Joseph E. “Kinetic Energy Z‘Bolte, Philip L., “Space Age Battle No. 5 (1984), p. 44. Penetrators Versus Armor.” ARMOR Maga-Tanks.” Defense and Foreign Affairs, Vol. 11 “Two Fiahtina Vehicle ConceDt Designs.” op cit., p. 3-2. ”Hoeltzel. et al. OD cit.. D. 19. Army Research, Development and Acquisition Magazine, Vol. 23 (Nov-Dec 1982), p. 19. ‘Bradley, Clifford D. “Fighting Vehicles: The Next Generation.” Army Research, Development and Acquisition Magazine, Vol. 22 (MayJune 1981), p. 63. 4Bradley, Clifford D. “Fighting Vehicles: The Next Generation.” Armv Research. Development and Acquisition Magazine, Vol. 22 (MayJune 1981). p. 63. 50gorkiewicz, Richard M. “Turretless Tanks?” ARMOR Magazine, Vol. 84 (Jul-Aug 1975), p. 14. GIbid, p. 15. ’2U. S. Department of Defense. Annual Report to the Congress - Fiscal Year 1986. GPO, 1985, p. 139. I3Ibid, p. 140. “Jenkins, D. H. C. “Autoloading in Tanks: Swings and Roundabouts for the Future.” International Defense Reuiew, Vol 17, No. 7 (1984), p. 907. 15Garner, F. “The Survival Probability of a Tank in Action.” Znternational Defense Reuiew, Vol. 17, No, 5 (1984). p. 612. W. S. Dept. of Defense, op cit., p. 194. 17Ibid. p. 194, ’BIbid, p. 199. Bibliography ’Backofen, Joseph E. “Tank - War Machine for Land Combat.” ARMOR Magazine, Vol. 89 (Jan-Feb 1980), pp. 10-12. 2Bradley, Clifford D. “Fighting Vehicles: The Next Generation.” Army Research, Development and Acquisition Magazine, Vol. 22 (MayJune 1981), pp. 1-3. 3Bradley, Clifford D. “What’s Next For The Tank?” ARMOR Magazine, Vol. 90 (Jul-Aug 198l), pp. 64-69. 4Garamore, Jim. “C-17 Program Seen Solution to Airlift Shortfall-” Army Times, 1 Apr 1985, p. 17. 5Geisenheyner, Stefan. “A Modem Tank Design.” Asian Defence Journal, Jan. 1984, pp. 29-31. 6Just, Wolfgang. “Mathematical Models in Modem Tank Development.” Armada International, Vol. 1, No. 1, (Jan-Feb 1977). pp. 20-23. TMans, Rowley. “Tanks Are Not For Bum-ing.” The Army Quarterly and Defense Journal, Vol. 114 (Jan. 1984). pp. 53-55. 80gorkiewicz, Richard M. “Tanks of the Future.” Military Technology and Economics, Vol. IV, No. 18 (1980). pp. 9-10. 40gorkiewicz, Richard M. “Trends in Tank Technology.” ARMOR Magazine, Vol. 89 (Jul- ’“Tappin, Stephen. “The Tank Comes Into Its Own Again: A Look At Recent Developments.” Canadian Defense Quarterly, Vol. 8, No. 4 (Spring 1979), pp. 16-21. ”Williams, Joseph. “Tank Innovations.” ARMOR Magazine, Vol. 84 (MayJune 1975, Aug 1980). pp. 8-14. PP. 34-36.

LINWOOD E. BLACKBURN.

a 1969 graduate of West Point, has served in cavalry and armor units in Vietnam, CONUS, and in Germany. He holds a master’s degree in industrial engineering and operations research from Virginia Polytechnic Institute. In addition, he is a graduate of the British Army Long Armour Infantry Course, the Command and General Staff College, and the Armed Forces Staff College. He is currently an instructor in the Defense Resources Management Education Center, Naval Postgraduate School, Monterey, California, and is now on orders for the 4th Battalion, 67th Armor in the

FRG.

ARMOR: The Magazine of Mobile Warfare 43