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J Leonard Johnson

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Name
  
J. Johnson


Died
  
1966

James Leonard Vincent "Len" Johnson (1905–1966) was an American scientist.

Contents

"Len" Johnson was an American engineer, designer, and scientist in the mid-twentieth century in the field of metallurgy and nuclear technology. He was one of the first Irish Catholics to break into the exclusive field of design engineering for the Department of Defense.

Len Johnson was born in Freeland, Schuylkill County, Pennsylvania in 1905. Though from an Irish family, Len was actually the 4th generation in the US. His great grandfather had immigrated from Moneyneana, County Londonderry, Ulster, Ireland in 1839, prior to the great Irish Famine. However, his roots in Pennsylvania and in America went back to the early 1700s.

The first member of his family to come to America was, Sir William Johnson (McShane) who originally came to the colony of New York in 1720. He managed his uncles properties and eventually created his own estate called Johnstown (town), New York. William rose to prominence in the French and Indian War as the Commissioner of the Iroquois tribe. He created and led an army of Indian and settler soldiers at various battles rising to the rank of Major General in the British army in America. The Battle of Lake George in 1755 earned him a baronet title and his capture of Fort Niagara with his Indian troops defeating the French army made him, "Johnson of New York". It is still an active baronetcy within the family. His grandmother was Ada "Mary" Wilson. Her family had been originally come to the US in the 1750s as Quakers outside Philadelphia. Len had an early grandfather, Captain Joseph Greene, who commanded the Northumberland County Ranger company at the close of the American Revolution in 1782, and had served in the York County militia from as early as 1777. Through his grandmother he was also a close cousin to President Woodrow Wilson.

His grandfather John was a collier engineer in Freeland, Pennsylvania, and his uncle, Captain Patrick Johnson, was an officer in the 116th Infantry Regiment of Pennsylvania, of the Irish Brigade and had fought at the Wheatfield at Gettysburg. Both were regionally famous musicians. His father, John Joseph "Jack" Johnson was the first Irish boss of the huge Cox Coal Company. It is estimated that Jack Johnson directed over 1000 workers on a day-to-day basis spanning six major installations to include a railroad. As a young man he was selected to be the first Irish boss and was educated by the company. After his formal education he was placed in charge of the entire field. That position allowed his son, Len, to enter into the prestigious Mining and Mechanical Institute (now MMI Preparatory School) from which he was graduated in 1922.

From there, Len became the first of his family to attend college. He chose to attend Pennsylvania State College (now University) and graduated with a degree in Mechanical Engineering in 1926. What to do after graduation proved to be a difficult decision to make in that he was offered a job with the professional baseball team system, the St. Louis Browns. He was a particularly good 2nd baseman and was playing semi-professional baseball at the time for the Allentown Dukes. However, he chose to go into engineering full-time, returning to the coal fields and went to work for Bethlehem Steel company through the 1920s. Len's work with new casting designs brought him greater attention and was eventually notice by U.S. Steel. In the 1930s he was hired and went to work for a US Steel affiliate, the National Tube works in Lorain, Ohio and then to McKeesport, Pennsylvania, where he became the General Manager of the entire plant. While there he wrote numerous articles on the advancements of steel use in the defense industry. He stayed until the late 1930s when he rose to become a designer of new steel products, leading the transition away from casting to the use of rolled steel.

World War II

U.S. Steel was starting to advance their weaponry design department in preparation for what would become World War II. Len went into the steel weapons design department and was on the team that first issued the patent for the rolled steel artillery shell, replacing those that were cast iron. This advancement increased the effective range of artillery shrapnel out to a bursting radius of fifty meters. Another design patent he made was the aluminum fuel blivet that would roll behind a jeep. Both designs are still used by the military today in some shape or form. It was due to his extensive work in metallurgical uses for the battlefield that brought Len to the attention of the OSS. In 1945, as the Chief Research Engineer for National Tube Company, he wrote the headlining article for the Yearbook of American Iron and Steel Institute. The article was titled "The Witter Process for the Manufacture of Shell Forgings and the Spinning Process for the Manufacture of Bombs". This article captured the sea-change the Steel Industry made in moving away from cast iron shells and into milled steel weapons.

Manhattan Project

For the majority of the war, Johnson and his family lived in Pittsburgh and worked on new metallic products. However, when his design expertise brought him to the attention of the OSS, he was moved into the Top Secret Department of Defense project to develop an atomic bomb.

He was brought into the Manhattan Project in the early 1940s and given a team whose job it was to develop two separate metallic imploding bomb casings. These two designs were later named "Fatman" and "Little Boy". As was common at that time, each cell of the Manhattan Project did not know exactly what it was that they were building. Such was the case for Len's design team. They did not realize it was the atomic bomb that they had worked on until the detonations over Japan in 1945.

After the war, Johnson left US Steel and the government. He spent the rest of the 1940s working the heavy machinery sales business. Following a successful career in business, Len returned to U.S. Steel to work new technology advances in the heyday of the steel industry, writing articles, and contributing breakthroughs to both academia and government. He eventually retired in 1964. He was married firstly to Ruth Scanlon (1910–1959), and secondly to Margaret Johnson. He had two sons and is buried outside Mount Lebanon, Pennsylvania. His service records were recently declassified by the Central Intelligence Agency.

References

J. Leonard Johnson Wikipedia