J. Walter Christie

John Walter Christie (May 6, 1865 – January 11, 1944) was an American engineer and inventor. He is best known for developing the Christie suspension system used in a number of World War II-era tank designs, most notably the Soviet BT and T-34 series, and the British Covenanter and Crusader Cruiser tanks, as well as the Comet heavy cruiser tank.

Early life and career
Christie was born in the Campbell-Christie House in New Milford, New Jersey on May 6, 1865. He started working at the age of sixteen at the Delamater Iron Works while taking classes at the Cooper Union in New York City. He eventually became a consulting engineer for a number of steamship lines and in his spare time did some work on early submarine designs. Following the Spanish-American War he developed and patented an improved turret track for Naval artillery.

At the same time he was working on designs for a front-wheel-drive car, which he promoted and demonstrated by racing at various speedways in the United States, even competing in the 1905 Vanderbilt Cup race. His car was knocked out of the race by a collision with Vincenzo Lancia who was at the time leading the race in a Fiat. Lancia was enraged, but presumably noticed the Christie car's vertical-pillar coil-based independent front suspension: the then unusual configuration subsequently turned up on the Lancia Lambda.

He was the first American to compete in the 1907 French Grand Prix: the V4 engine of 19,891 cc that powered his vehicle was the largest ever used in a Grand Prix race, but the car retired after four laps with "engine trouble". On September 9 of that same year, Christie was seriously injured in a crash when his car struck loose debris during a lap at Brunots Island Race Track in Pittsburgh, Pennsylvania. In a twelve-car endurance race earlier that day, scheduled to run 50 miles, the Haynes car of driver Rex Reinertson had lost its right front tire with disastrous results, catapulting into the air and landing on its roof. Reinertson was crushed beneath the car, suffering injuries (including a skull fracture) that ultimately proved fatal, and his mechanic Clarence Bastion was ejected from the vehicle and thrown 50 feet through the air, breaking both of his arms and both of his legs. After ten more laps, the race was stopped so that the injured men could receive medical treatment, and the unlucky Reinertson's car was cleared off the track. Next up was Christie, driving the car he had used at the Grand Prix only a few months before. He was attempting to break the track's lap record of 58 seconds, and due to receive a $500 prize if he was successful. Christie completed the second half of his warmup lap in only 24 seconds, so he was well on pace for a new record, but at the 1/8 mile marker of his real lap his right front wheel struck part of Reinertson's car that remained on the track. Christie was thrown from the car, traveling twenty feet in the air and fifty feet across the ground, before coming to earth. Mark Baldwin, a former Major League Baseball player who became a doctor following his retirement from professional sports, happened to be in the stands as a spectator, and he ran to Christie and administered first aid until Christie could be placed in an ambulance and taken to the hospital, a task that was complicated by the large number of spectators who had climbed down from the grandstands and moved onto the track. Christie had been knocked unconscious by the impact. He also sustained a broken left wrist, a cut on his right eye from the broken glass of his goggles, and a significant injury to his back. Doctors who treated Christie expressed concern that he might be crippled as a result of his injuries, or lose the sight in his damaged eye, and news of his accident was kept from his wife, who was herself seriously ill at their home in River Edge, New Jersey. Christie remained in the St. John's Hospital until September 19, at which point he was discharged and returned to New York.

Christie now switched his energies away from automobile racing to developing his fwd New York taxicab design. With benefit of hindsight, the taxi design's importance came in large part from the fact that it incorporated a transversely mounted engine/transmission assembly, applying a basic architecture that would be greeted as revolutionary when applied by Alec Issigonis in the BMC Mini fifty years later. However, in 1909 the idea of a 'conventional lay-out' was less firmly rooted than it would have become by 1959, and for Cristie the vehicle's more striking novelty lay the fact that the entire "forecarriage", incorporating all the key mechanical components, could be detached and replaced in "less than one hour", so that the vehicle could stay on the road while the engine maintenance took place. The car's radical lay-out was to necessitate the manufacture of many complex components in-house, and problems encountered subsequently by other manufacturers producing or finding a dependable universal joint make it hard to believe that the Christie vehicle was particularly dependable. Given the heavy steering resulting from the fwd lay-out and a published unit price in 1909 of $2,600, it is understandable that the denizens of the New York cab trade did not flock to buy the Christie taxi.

In 1912 Christie began manufacturing a line of wheeled fire engine tractors which also utilized a front-wheel-drive system, and subsequently sold scores of them to fire departments around the country, most notably the New York City Fire Department. The tractors allowed the departments to keep their steam-powered pumps while ending the use of horses to pull them to the scene of the fire.

In 1916, with the First World War raging in Europe, he developed a prototype four-wheeled gun carriage for the US Army Ordnance Board. But the Ordnance board had set out strict guidelines for weapons, and Christie refused to revise his designs to suit their requirements. Christie's own personal stubbornness and his habit of offending those in the US Army and Ordnance bureaucracy would have ramifications for the rest of his career.

Christie's first major supporter, and success, however came not from the US Army, but the United States Marine Corps Major General Eli K. Cole who was an advocate of developing the Marine Corps amphibious capability. Christie had built an amphibious light tank a decade before Donald Roebling's Alligator, and this was to be displayed during the Winter Maneuvers of 1924 at Culebra, Puerto Rico. In overall command of the exercise was Admiral Robert E. Coontz, USN. Along with trying out the a “Beetle Boat,” a copy of the armoured lighters used by the British during the Gallipoli landings in 1915 that served as a landing craft, would be Christie's amphibious tank first recommended by Brigadier General Smedley Butler. The tank was transported to the exercise area aboard the USS Wyoming (BB-32), and designated as the Marine Corps Tank (GC-2). It was then hoisted on board a waiting submarine prior to its launch toward the shore, then "As the “mother ship” submerged, the Christie tank proceeded to shore. Unable to maneuver through the heavy surf, the vehicle returned to the Wyoming without landing. The next day, when the surf had subsided, the Christie amphibian once again left its mooring aboard the submarine and made a perfect landing. Despite the fact that the vehicle came ashore after the exercise had been officially declared over, Cole stated that the tank possessed the capability of being developed into an extremely valuable weapon, especially in connection with landing operations."

Later innovations and bureaucratic frustrations
Christie continued to submit designs to the Ordnance board, but none was deemed acceptable. A major reason was the poor cross-country performance, due to limited suspension capabilities. He turned his attention to this problem, and after five years of development (at a cost of $382,000) he produced the revolutionary prototype tank chassis M1928 (Model 1928) design. He proudly referred to it as the "Model 1940" because he considered it to be 12 years ahead of its time. The M1928 still retained large road wheels with no return rollers for the tracks from his earlier designs, so that the tracks could be removed for road travel, allowing for greater speed and range. What made this prototype revolutionary was its new "helicoil" suspension system, whereby each wheel had its own spring-loaded assembly. This reduced space in the interior of the tank, but (combined with a very light overall weight) allowed for unprecedented high-speed cross-country mobility, albeit at the cost of extremely thin armor. Another interesting feature of the M1928 and later Christie designs was sloped armor in front, which could better deflect projectiles. The sloped armor helped to compensate for its thinness. The Army purchased several of Christie's tank prototypes for testing purposes and Christie's patent, allowing them to produce prototypes based on his design.

In October 1928, the M1928 was demonstrated at Fort Myer, Virginia. There the Army's Chief of Staff, General Charles P. Summerall, and other high-ranking officers were impressed and strongly recommend that the Infantry Tank Board conduct further, official tests of the new vehicle. However, the Tank Board was less than impressed. They pointed out that the vehicle's armor was very thin and could not survive penetration by the smallest armor-piercing antitank rifle or artillery piece. The Board also differed with Christie on guidelines for tank capabilities, which were based on a radically different theory of armored warfare than that adhered to by Christie. While Christie advocated the use of lightweight tanks with long range and high speed, designed to penetrate enemy lines and attack their infrastructure and logistics capabilities, they saw the tank as simply a supporting weapon to facilitate breakthroughs by the infantry, and help isolate and reduce enemy strongpoints near the front lines, much as they had been used in the previous world war. For the Infantry Tank Board, armor and firepower were far more important design criteria than mobility, and the M1928 prototype was passed to the Cavalry for further evaluation.

The Cavalry's thinking at that time was geared toward armored cars, and wanted to develop the M1928 as an armored car chassis. Once again, Christie's concept of how his vehicles should be used, together with his difficult nature, resulted in clashes with Army officials. One member of the Cavalry Evaluation Board who appreciated both Christie's design and tank warfare concepts, was Lt. Colonel George S. Patton. Patton, and his friend Major C.C. Benson, strongly supported adoption of the M1928 as the basis for a Cavalry tank.

Ultimately, the Secretary of War rejected mass production of the M1928, citing excessive acquisition costs. Embittered, Christie felt he was justified in selling his inventions to the highest bidder. He began looking to foreign governments to purchase his advanced chassis and suspension systems; Poland, the Soviet Union and Great Britain had all expressed interest in the designs. A long and complex series of exchanges between Christie and foreign governments followed. These were technically illegal, since Christie never obtained approval of the US Department of State, Army Ordnance, or the Department of War to transfer his designs to potentially hostile governments.

Dealings with foreign governments
Initially, Christie promised to sell his M1928 tank design to the Polish government. In 1929, Captain Marian Rucinski of the Polish Military Institute of Engineering Research (WIBI) was sent to the USA, and soon learned of the M1928 tank being constructed by Christie's company, the US Wheel Track Layer Corporation in Linden, New Jersey. Rucinski also learned of a design for an improved tank (later known as the Christie M1931) that had recently gone to blueprint. Rucinski's opinion was so enthusiastic that on February 16, 1930 a special acquisition commission was dispatched to the US, headed by the Chief of the Engineering Department, Colonel Tadeusz Kossakowski. The commission signed a contract with Christie in March for construction and delivery of a single M1928 tank, and paid a pre-payment to him. Christie later reversed course and failed to deliver on his contract obligations, and faced with potential litigation, eventually returned the payment made by the Polish government, which never obtained the tank they had ordered.

Though the Soviet Union had no diplomatic relations with the US at the time, and was barred from obtaining military equipment or weapons, Soviet OGPU agents at the trade front organization AMTORG managed to secure plans and specifications for the Christie M1928 tank chassis in 1930 using a series of deceptions. On April 28, 1930 Christie's company, the U.S. Wheel Track Layer Corporation, agreed to sell Amtorg two M1931 Christie-designed tanks at a total cost of $60,000 US, with the tanks to be delivered not later than four months from date of signing, together with spare parts to the purchased tanks for the sum of $4,000. Rights were also transferred to the production, sale and use of tanks inside the borders of the U.S.S.R. for a period of ten years. The two Christie tanks, falsely documented as agricultural farm tractors, were sold without prior approval of the U.S. Army or Department of State, and were shipped without turrets to the Soviet Union. The Soviets later improved upon the basic Christie tank design, adopting its sloping front armor for its BT tank series of infantry tanks. The BT itself was further refined into the famous Soviet T-34 tank of WWII, retaining the sloping front armor design, now adopted for side armor as well.

Following favorable reports on observation of the Soviet activities, the British War Office arranged purchase of Christie's last remaining prototype and licensing of a Christie design through the Morris Motors Group. The deal was done by phone for £8000. However, the British discovered that Christie had already mortgaged the vehicle and had to pay that as well. The US authorities refused its export as it was war materiel. The vehicle was dismantled sufficiently to meet specification as an "agricultural tractor" and so be exporter. The removed parts were then shipped to the UK in crates marked as "grapefruit". Christie's design still had a number of faults that he had never addressed and though the general features were retained, the design was completely reworked to form the British Cruiser Mk III (A13).

Later life and work
After the U.S. Army's rejection of the M1928, Christie continued to work on new designs throughout the 1930s, including a winged tank. Though the Army purchased several prototypes and developed its own experimental designs based on Christie designs, none of the Christie designs ever saw mass production by the US.

Following the outbreak of World War II in 1939 and the US entry into hostilities in 1941, Christie again submitted tank designs to the army, all of which featured his suspension system and large, convertible road wheels. But as with his earlier dealings with the army, attempts to secure US government adoption ended largely in frustration and rejection. He died in Falls Church, Virginia on January 11, 1944, nearly broke, as the tanks based on his designs were shaping the course of history.