Christie’s Last Hurrah

,Christie’s Last Hurrah In 1941, the Army Reappraised the Christie Suspension For Use on Tank Destroyers by George F. Hofrnann, PhD. As the U. S. Army entered World War 11, its nical experts focused on away to stop the tanks that spearheaded the German blitzkrieg. The dochine that emerged created the Tank Destroyer Command - and the need for a fast, maneuverable tactical and tech-Christie and his son engineered this drawing of an airborne tank concept, developed dunng WWII. It clearly shows details of the coiled spnng suspension. vehicle capable of carrying a powerful antitank gun. This search for the ‘‘ideal tank destroyer” spurred reconsideration of the Christie suspension system, which the Army had explored and rejected in the 1930s. despite the fact that the system was adopted by the British and the Soviets.’ The Christie suspension, patented by the outspoken and cantankerous inventor J. Walter Christie, used heli-cally-wound coil springs acting independently on each of the suspension’s road wheels. While the Christie vehicles purchased for tests by the Army in the 1930s had not proven particularly durable, there was the potential for higher speed and maneuvenbility inherent in this type of design, something that was not possible in the volute-bogie type of suspension used in the American medium and light tanks of the day. Indeed, Christie himself had demonstrated the possibilities of his machines in numerous flashy public exhibitions backing up his boast that a tank could obtain high speed. Two excellent recent studies of U. S. tank destroyer dochine in Wwn recount the struggle to come up with concepts and suitable vehicles to mount a defense against the German panzers and their tactics of blitzkrieg? The concepts grew from the work of a special War Department G-3 planning staff appointed by General George C. Marshall in May 1941, under the direction of LTC Andrew D. Bruce. Charged to tackle “such unsolved problems as measures against armored force action,” the group came up with the concept of a separate tank destroyer branch equipped with special vehicles. The doctrine, found wanting as the war progressed, determined that tanks would not fight tanks. Instead, tank destroyers would aggressively react to armor breakthroughs. At first, this new branch was equipped with towed guns and “portee” guns, field guns on halftracks, but soon the search continued for the “ideal tank destroyer.” The War Department planning group ultimately urged development of a lightweight tracked vehicle possessing speed and maneuverability, capable of carrying an adequate gun, and lighter than a tank, even at the expense of some protection: The group urged that in the search for more speed and maneuverability the Army reconsider Christie’s independent coil spring suspension. This recommendation was not welcomed by the Ordnance Branch, which had squabbled frequently with the strong-willed, eccentric Christie during tests of his designs in the 1930s. Ultimately, Christie sold his ideas to the British and the Soviets, who further developed the Christie suspension in two series of fast light tanks, the British “Cruisers” and the Russian BTs. Instead, the United States had continued to develop the volute-bogie system, which, despite its reliability, had by the 1940s begun to reach its developmental limits. Ordnance tests had proved that the volute-bogie suspension system used in all early U. S. Army tanks would not permit the desired speed and maneuverability? Nevertheless, some Ordnance personnel were “bitterly opposed” to Christie’s system. By December 1941, however, Bruce was able to get a memorandum from G-3 issued to G-4 recommending a 37-mm Gun Motor 14 ARMOR -

Carriage using a Christie type suspension. This decision was influenced by observations made by LTC L. W. plates, Schilling eliminated the outside plates on each side of the vehicle, exuosing; the long The Bigley Gun Motor Carriage arrives for evaluation at Aberdeen Proving Ground in spring 1941. (National Archives) Tharp, a G-3 General Staff officer from the Planning Branch and a strong supporter of the Christie design. In October he visited William Bigley, a private entrepreneur, who had acquired a Christie tank chassis. His report indicated the vehicle appeared to be an ideal self-propelled mount suitable for the ’I’D Command and capable of mounting any gun smaller than the 3-inch antiaircraft gun. The following month, at Aberdeen Proving Ground, LTC Tharp inspected a British cruiser tank with the Christie suspension. He was impressed with the tank’s smooth ride and stable gun platform, noting that its suspension system had been adopted by foreign countries. Based upon LTC Tharp’s reports and observations, G-3 decided to develop the Christie concept into a TD. In January 1942, negotiations began between General Motors Corporation (GMC) and the Tank and Combat Vehicle Division of the Ordnance Department in order to study the details of Christie suspension patents controlled by Army Ordnance. Also considered in the negotiations was William Bigley, who had been in contact with General Motors regarding manufacturing rights of his acquired Christie chassis? It was not until the middle of March that action was finally taken: then-BG Bruce, who was dissatisfied with the numerous vehicles undergoing tests by the Ordnance Department, took the initiative and conferred with W. J. Davidson of General Motors. Consequently, an engineer from GMC, Robert Schilling, designed a 37-mm Gun Motor Caniage with a modified Christie suspension? Before the Ordnance Department could designate the proposed TD as the T42, it was redesigned early in April 1942 to mount a U. S.-made British 57-mm gun and redesignated as the T49. Two test vehicles were subsequently ordered from Buick Motors? Schilling’s design deviated from the original M1928 and M1930/31 Christie suspension by replacing the large road wheels with smaller ones, adding track support rollers, and eliminating the forward bell-cranks. The modified design, however, did retain the long helical springs so characteristic of Christie’s earlier vehicles. In an attempt to modify the wasted hull space due to the springs’ position between - - helical springs. In the spring of 1941, Bigley had unsuccessfully attempted to sell the War Department his acquired Christie chassis. The Aberdeen Proving Ground test indicated the tracked vehicle had a number of mechanical problems with the power train and the clutch-brake system of control. This chassis had a very interesting history. It was originally built by Christie and called the High-speed Tank, Model 1937, 1938 and the T12, depending upon what year modifications were made. The vehicle was fmt tested in December 1937, and typical of Christie, he staged this test before the public, at Westfield Airport in New Jersey. An Ordnance Department observer was impressed with the “machine’s very attractive appearance;” but in his opinion there were no new design features of striking importance. He concluded that the en-Christie tank chassis Mi937 is tested at Westfield, N. J. in December 1937. (Royal Armoured Corps Tank Museum) ARMOR - 15 gine would easily overheat with an added superstructure, armament and ammunition, and crew.8 After the demonstration, Christie made arrangements to ship the tank chassis to Famborough Proving Grounds in England for tests scheduled in February

1938. Then-LTC G. MacLeod Ross, who at that time was involved in tank design at Woolwich, remembered Christie’s showmanship, describing him as “an escapee from Bamum and Bailey’s circus....”9 Another observer from the Royal Tank Corps, SGT A. Norris, recalled that during the first test-run attempt, the final drive seized up, bringing the chassis to a bruising, abrupt halt. This resulted in a number of damaged gear components; Christie’s driver had forgotten to check the transmission oil. Christie was furious and refused assistance from his British hosts, preferring instead to acquire the replacement parts and fur the machine himself.” Other than its speed, the chassis did not impress the British observers at Famborough; they had purchased late in 1936 a Christie Model 1930, which was similar to the U. S. Army’s Medium Tank T3 and the Combat Car T1. The British had already acquired enough technical information from this vehicle. Perhaps what soured the possibility of purchasing a second model was Christie’s insistence that he receive $320,000 to cover actual manufacturing cost of parts and drawings, and future manufacturing rights for current and future test models.’ Returning to the United States, and after a few modifications, the chassis - now called Model T12 - was again subjected to a brief test in October 1938 at Hempstead, Long Island. As before, an Ordnance Department observer was on hand to examine the vehicle. He noted that Christie’s sus- T67 75mm Gun Motor Carriage Icks Collection. Patton Museum pension provided excellent riding qualities and a stable fuing platform. However, there was again considerable concern regarding the effect the added weight of increased armor, armaments, and crew would have on the power train.12 In March 1939, Christie attended an Ordnance conference on tanks at which he virtually demanded the War Department let him undertake the construction of a large number of his tanks. If not, he threatened to use an organization of civilians he had and through which a sufficient number of Christie tanks would be furnished to each college in the United States for training. When asked to be more specific about his proposition and then submit it to the Chief of Ordnance, Christie left the conference, announcing he would first see President Roosevelt13 This was Christie’s last official contact with the U. S. Army. He was not consulted in 1941 or 1942 by GEN Bruce, COL Tharp, nor GMC engineers in regard to the modified suspension design for the TDs. With no military customers and serious financial problems over an artisan’s lien and attorney fees, Christie sold the chassis in August 1939 to William Bigley. It was destined to become the Bigley Gun Motor Carriage. I4 This vehicle was powered by anew 190-hp. Continental engine and new tracks. The late COL Robert J. Icks recalled Bigley bringing the vehicle - now sporting an open, odd-looking superstructure of mild steel - to APG in May 1942 for an unofficial proving grounds test. As during the previous spring, the chassis tested poorly and was returned to its owner. That was the last time Icks and APG saw the Christie/Bigley tank chassis.15 Nevertheless, Bigley had been consulted by GMC officials regarding the Christie suspension but was advised that this system was being developed 16 ARMOR - by the Buick Division. In October, however, Bigley again attempted to interest a special Army Armored Board in his vehicle. Though the Buick-designed T49 provided the mobility and maneuverability the TD Command desired, there were definite indications that summer that there would be a need to upgun the vehicle in order to enhance its firing power. In July, a decision was made to mount a 75-mm gun on the second pilot model, and by the fall, the vehicle was ready for proving ground tests. Meanwhile, a special Armored Vehicle Board (also called the Palmer Board) was created by the Army Ground Forces to deal with the various A F V s created as a result of America’s entrance into the war, and at the same time attempt to place some semblance of order and control on the uniformity of equipment used by the using arms. The board, chaired by BG William B. Palmer of the Armored Force, considered some 15 vehicles between October and December 1942, including the Bigley vehicle and the T49. The first pilot T49, much to GEN Bruce’s gratification, survived the board‘s scrutiny. While the board was in session, the redesigned second pilot T49 was redesignated in November as “75-mm Gun Motor Carriage, T67” with Christie-type suspension. The board concurred and recommended the T67 be further developed and implement “...changes as may be found necessary, with a view to standardization...” as soon as possible. However, Palmer had “serious misgivings” about Bruce’s desire to develop a 76-mm gun motor carriage, and requested that he “take an ‘antitank’ role and give up the nimble hide-and-seek panther lines....” The Palmer Board believed in continuing the T49P67 development with a 57- mm or 75-mm gun.16 On 30 October, Bigley offered his vehicle to the Palmer Board for an APG test, particularly as a potential The rejected Bigley vehicle, as tested in 1942. and considered by the Palmer Board, with mock-up body. (Icks Collection: Patton Museum) TD. The board deferred consideration of this vehicle until the T67, which embodied the modified Christie suspension in improved form, underwent its tests. Finally, on 20 November, the board members conferred with Bigley regarding serious concerns they had about his vehicle, based upon its past history. Consequently, on 24 November, GEN Palmer wrote Bigley and noted that, regarding his vehicle, “...no specific combat purpose has been stated: the body is not designed for any specific military purpose: and none of the requirements as to loading are met.” By 4 December, the board made its final decision on the Bigley vehicle and unanimously recommended its consideration be terminated, because the vehicle “...could not be compared with carefully engineered military vehicles canying their full combat loads.” In addition, in the board’s opinion, the Bigley vehicle’s suspension was not much of an improvement over Christie’s earlier models, and the T49 employed the same suspension in an improved form. None of the using arms represented on the board - the Armored Force, Cavalry, and the Tank Destroyer Command - were interested in development of the Bigley Gun Motor arriage.’ Early in January 1943, two major events had a marked effect on AFV designs.’* First, the fourth and final cbn,g&h tbe TD gun took place when the 76-mm replaced the 75-mm gun. Earlier in September, Ordnance had called to GEN Bruce’s attention anew lightweight, high-velocity 76-mm gun. This new gun would provide the TD Center with alight, highly mobile, low-silhouette, lightly armored vehicle with the striking power of the 76-mm gun. Finally, GEN Bruce’s perception of an ideal TD was achieved. The vehicle was designated “76-mm Gun Motor Carriage, no,” and eventually evolved into the M18 “Hellat.”’ The second and the most important technological change occurred when the Christie suspension was replaced by an Ordnance designed torsion-bar system. This suspension would have a dramatic impact on tank designs for many decades. The decision-making process for this action rested in the Subcommittee on Automotive Equipment, which formed recommendations on military characteristics and production capabilities and forwarded them to the Ordnance Committee for approval. On the subcommittee were members of the using services and Ordnance personnel, the Army’s experts in tank design and engineering. The Ordnance Committee Minutes (OCM) recorded important information and references on developmental events. Three influential Ordnance ARMOR - 17 persons sat on the Subcommittee on Automotive Equipment when the decision was made at the end of 1942 to drop the Christie-type system and replace it with the Ordnance design. The key subcommittee member was the chairman, BG Gladeon M. Barnes, who since 1938 had played a dominant role in Ordnance research and design. The second key committee member was BG John K. Christmas, an engineer and tank designer. The third member was LTC Joseph M. Colby, a protege of GEN Barnes. Both Barnes and Colby also acted as consultants for the Palmer Board. Later, General Colby claimed he was involved as early as 1933 in designing a torsion bw, however, he recalled, “I was never in the position to get funds for its development until the winter of 1942-3.*920 Instead, patents for the torsion bar were granted to Barnes and Warren E. Preston on 17 December 1935 and on 17 November 1936 to Barnes. It was Generals Barnes and Christmas who attended the Ordnance conference in October 1939 when Christie made his grandiose statement that he would provide his tank to every college in the United States and then stormed out of the meeting, claiming he was going to see the President2I The decision to use the torsion bar in the ‘I70 was made because previous experience with the Christie system demonstrated that the side-mounted, long, helical springs com-After examining and rejecting Christie‘s coil-spring suspension, Ordnance decided to use the torsion bar system on the M18 “Hellcat” tank destroyer. promised the space needed for the crew and fighting compartment, especially in light of the fact that the gun motor carriage was continuously u p gunned. The torsion bar layout did not compromise a most critical combat vehicle dimension, its width, and did not cramp the interior fighting space. The torsion bars were installed horizontally, extending across the underside of the vehicle behind the protection of an armor plate. In addition, it was demonstrated that the torsion bar had a greater shock-absorbing capacity than the modified Christie and the earlier designed volute-bogie suspension systems. Another concern that arose as a result of experiences with the Army’s Christies during the 1930s was that the vehicle’s wheels tended to jump the tank tracks on turns. The torsion-bar suspension virtually eliminated this operating difficulty?2 Thus ended the U. S. Army’s last attempt to use the Christie suspension. However, the confusion between the Christie and torsion-bar suspensions gave rise to mistaken identification. The official Ordnance Department History of World War I1 claimed this confusion accounted “...for much of the criticism of the Ordnance D e m e n t ’ s rejection of Christie’s design.”723 For example, when the fmt group of “Hellcats” arrived in England before D-Day, the CG of the 6th Armored Division, MG Robert W. Grow, noted, “...they are the M18 (old T70) 76-mm gun on Christie suspen- i o n. ” During the Battle of the Two Christie designs adopted by other countries - at left, the Bribsh Cruiser Mk 111; above, a Soviet BT-series tank of the 1930s. (Icks Collection: Patton Museum) 18 ARMOR - November-December 7997

Bulge, a I11 Corps Periodic Report, "Know Your Tanks," advised all units in the 4th Armored Division receiving replacement tanks that some "...with 76-mm gun... Christie suspension, low silhouette could be "...misidentified as German tanks. The report further cautioned all unit commanders to take serious note of this matter so friendly fire did not engage "our tanks of this Years later, the Chief of Ordnance during the war, LTG Levin H. Campbell, Jr., noted that he supported Christie and his designs early in the 1930s. until military requirements changed. He considered Christie a good inventor, "but like many such civilians, Christie felt he had to go it his way." Christie, according to LTG Campbell, expected Ordnance to use his designs, rather than accept military requirementsF6 Christie could not, nor would not, accept the committee approach to research and development that became so prevalent after World war I. type+ Notes 'George F. Hofmann. "The United States' Contribution to Soviet Tank Technology," V125:l Journal of the Royal United Services Institute for Defense Studies (RUSI) (Mar. 1980). Whitehall, London. pp. 63-8, and "The Troubled History of the Christie Tank," ARMY (May 1986). pp. 54-65. Charles M. Baily. Faint Praite: American Tanks and Tank Destroyers during World War I1 (Archon Books: Hamden. Conn.. 1983). and Christopher R. Gabel, Seek, Strike and Destroy: U. S. Army Tank Destroyer Doctrine in World War 11. Leavenworth Papers No. 12. Combat Studies Institute. (USACGSC Fort Leavenwolth. Kan., Sep. 1985). Also see Baily, "Tank Destroyers," ARMOR (Jul-Aug 1979), 3Letter, MG Andrew Bruce to MG Orlando Ward, 28 Nov 1949. Folder: TD Development, Box: Tank Destroyer Center, The Andrew D. Bruce Papers. U. S. Army Military History Institute (USAMHI). Carlisle Barracks, Pa. 4Em0ry A. Dunham, Tank Destroyer Hittwy (not published), AGF Historical Study No. 29. 1946, Record Group 337. National Archives, Washington, DC, p. 53; Joseph E. Canning. "Faster Combat Vehicles: New Torsion-Bar Suspension Provides Greater Speed and Reliability," Army Ordnance (Jul-Aug 1945). Pat-pp. 7-13. ton Museum of Cavalry and Armor. Fort b o x. -btter. Bruce to Ward, op. cit; Memorandum, Office of the Chief of Ordnance, 0.0. 472.1/39% (G-3/46176), 2 Dec 1941, Record Group 156. NA, Washington National Record Center, Suitland. Md., and Subject: Visit to... the Bigley Tank. 22 Oct 41; Subject: Visit to Aberdeen. 13 Nov 41; Subject: Development of 37-mm Gun Motor Carriage with Christie Suspension. 3 Jan 42. G-3/46176. War Department General and Special Staffs. Record Group 165. NA. Ky.. p. 94-5. 6Tank Destroyer History, op. cit. 'Subject: 57-mm Gun Motor Carriage. T49 - Development Recommended, Ordnance Committee Minutes (OCM) Item 18039, 9 Apr

1942. RG156, NA.

*Subject: Christie Convertible Chassis, 0.0. 451.2511384,15 Dec 1937: Subject: Demonstration - Christie Tank, 0.0. 451.25f7385. 16 Dec 1937; Subject: Resume of Data on Christie Tank for use in "Hearings." 0.0. 451.25/7467.

RG 156, NA.

9G. MacLeod Ross. The Business of Tanks (Elms Court. England: Arthur H. Stockwell 'OLetter, A. Noms to Col. Peter H. Hordean. 23 Nov 1970. Royal Armoured Corps Tank Museum, Bwington Camp, Wareham. Dorset. England. "A.13. El, E2 and E3: Notes on Development, ND, Letter. W. J. Christie to War Office, 28 Feb 1938, Royal Armoured Corps Tank Museum. '*Report of Inspection of Christie Tank at Hempstead, LI.. 0.0. 451.25/8209. 10 Oct

1938, RG156. NA.

I3Subject: Conference on Christie Tank 0.0. 451.25/8674,16 Mar 1939, RG156, NA. 14AGREEMENT. 7 Aug 1939. betweem CHRISTIE CHASSIS, INC.,... and William Bigley, J. Edward Christie Files. 'btter, Col. Robert J. lcks to author, 18 Aug 1977. 16Subject: 75-mm Gun Motor Carriage T67 (Based on 57aun Motor Carriage T49 Chassis) - Development and Manufacture of Pilot Vehicles Recommended. OCM Item 19185, 10 Oct 1942; Minutes of the Ordnance Committee Meeting No. 51.19 Dec 1942, all RG156; "Report of Special Armored Vehicle Board" and Exhibit J, AG451. dated 13 Oct 1942, submitted 5 Dec 1942. Records of the Adjutant General's Office, RG407. NA; Letter, BG W. B. Palmer to BG Andrew Bruce, 9 Dec 1942. and Letter, BG Andrew Bruce to BG W. B. Palmer, 26 Jan 1943, Bruce Papers. USAMHI. ""Report of Special Armored Vehicle Board." op. cit, Exhibit 0. '*Minutes of the Ordnance Committee Meeting No. 1. 7 Jan 1943; Subject: 76-mm Gun Motor Carriage '170 (Based on 75-mm Gun Motor Carriage T67 Chassis) - Development and Manufactured of Pilot Vehicles Recommended, OCM Item 19438.4 Jan 1943, RG156. NA. Ltd., 1976). pp. 147-9. ARMOR - '9Extractr of Chapter IX. The Tank Destmyer Board. Tank Destroyer History. 1 Dec 1941-1 Sep 1943. BNLX Papers, USAMHI, pp. 2-3. %etter, BG Joseph M. Colby to author. 27 Feb 1970. z'Conference on Christie Tank, 16 Mar 1939. op. cit. U n g. "Faster Combat Vehicles," op. cit.; Constance McLaughlin Green, Harry C. Thomson and Peter C. Roots. The Ordrurnce Department: PLNling Munitions For War (Washington: G. P. O.. 1955). fn 106, p. 200. For a detailed description of the 'I70 suspension see Chapter 3 "Suspension" in War Department Technical Manual TM 9-1755B. 29 Jan 1944, Patton Museum of Cavalry and Armor. 23The Ordnance Department: Planning Muni-tiom For War, op. cit. p. 200. %nterview, author with MG Robert W. Grow, Retired. 17 Aug 1971: Grow Diary. 22 May 1944, Falls Church, Va. zs6th Armored Division G-2 Periodic Report lt108, 28-29 Dec 1944. Archives Branch,

USAMHI.

261nterview. author with LG Levin H. Camp bell, Jr.. 18 Aug 1973. Annapolis, MD. Dr. George F. Hofmann is a businessman, historian, lecturer, and author who served in U. S. Armor in 1957-59. He holds a BS degree in business administration and a masters in education from Xavier University, a masters in American history and a doctorate, concentrating in diplomatic and military affairs, from the University of Cincinnati, where he is currently a lecturer. A number of his articles have appeared in ARMOR, and he has also published in Army, Marine Corps Gazette, Milifary Affairs, and the Journal of the Royal United Services Institute. He is the author of The Super Sixth, a history of the 6th Armored Division, and soon to be published by Kent State University Press, Cold War Casualty: The Court-Martial of Major General Robert W. Grow. 19