Hybrid Tank the Holt Petrol Electric

Benjamin Holt arrived in California in 1883 from New Hampshire to join his brothers. his oldest brother Charles had settled in San Francisco in 1864 and set up the C. H. Holt and Company which produced wooden wheels for wagons. William Holt and Ames Holt had arrived in 1871.Hybrid TankThe Holt brothers then formed the Stockton Wheel Company and moved to Stockton, about 90 miles east of San Francisco. Benjamin was not only an entrepreneurial, he was also a mechanical genius. In 1890, he built his first steam traction engine, which he called “Old Betsy”.

In 1892 the company name was changed to Holt Manufacturing Company. The company now were producing a steam traction engine that could pull a load of nearly 50 tons at 3 M.P.H.

Looking for new ideas, Benjamin was thinking along the lines of a continuous track. He decided to go to England in 1903, where the crawler track was being developed.  Although the idea was good in practice the track failed to work as was intended.

Benjamin returned to California and set to work, by the end of November 1904 he successfully demonstrated the first successful continuous track tractor. He had overcome the problems and went on to develop a range of successful tractors. In the Great War Holt tractors were used to pull the large artillery pieces and supplies. There were three models used by the British and French on the western front; the Holt 120, the Holt 75 and the Holt 60. some 10,000 Holt tractors would be used during the war.The hybrid Tank was built during 1917-1918 by the Holt Company with the electrical units being provided by the General Electric Company. The tank weighed about 25 tons with a top speed of 6 mph and was 16 1/2 feet long, nearly 8 feet tall and 9 feet wide and had a crew of six.

The tank was based on the Holt Model 75 with a lengthened version of the suspension.  Power came from a Holt 4-cylinder petrol engine producing some 90 horsepower, this was connected to a General Electric generator, producing power for the two electric motors one driving each track. A similar method had been used earlier on the French Saint-Chamond tank, which also ran on the Holt track system.The hybrid Tank had a 75 mm gun placed low in the V-shaped nose and Browning 303 machine guns in sponsors on each side. The engine and transmission were rear mounted, a problem which had to be overcome was the overheating of the transmission. The Holt Company came up with a  a complicated water cooling system to try and solve this issue.

Only one prototype was built, but unfortunately in testing it proved to be unsatisfactory. Its climbing ability was poor and because of its short tracks it was unable to cross the trenches that the Germans had been constructing on the western front and it turned out to be much heavier than planned. work on the Hybrid Tank was then stopped and it was abandoned.

Colonel Swinton visited the Holt Manufacturing Company in Stockton, California in April, 1918 while on a tour of the USA. The Colonel publicly thanked Benjamin Holt and his workforce for their contribution to the war effort During the Great War.

Colonel Ernest Swinton who together with engineers of the William Foster & Company came up with the idea and constructed the first tank during August and September 1915, it was nicknamed ‘Little Willie’ and can be seen at the Bovington Tank Museum in Dorset, England.