In 1901, Pratt & Whitney, which was still a machine company, was bought by Niles-Bement-Pond, an Ohio manufacturing conglomerate. The company continued to make manufacturing tools and still continues today as Pratt & Whitney Measuring Systems, located in Bloomfield, CT. Read our CT Legends story about Francis Pratt and Amos Whitney.

Opportunity in Hartford

At the end of World War I, a man named Frederick Rentschler helped form a company called the Wright Aeronautical Corporation (headquartered in New Jersey) that built liquid-cooled engine aircraft. Rentschler helped design the company’s planes, which performed well in the popular Pulitzer Trophy Races. To improve its success, Rentschler led the company to begin building air-cooled engines. Eventually, however, the company board refused to financially back his work to create more powerful engines, and Rentschler resigned.

Rentschler was a well-connected man. From his brother he learned about the Pratt & Whitney Machine Tool Company, which at the time had excess space and excess capital. In addition, a family friend of Rentschler happened to be the president of Niles-Bement-Pond. In July 1925, Rentschler had a meeting with the board of Pratt & Whitney and his plans for a large, air-cooled radial engine impressed them enough to reach an agreement. Using the Pratt & Whitney name, he could develop the prototype for his innovative engine and obtain the financial backing for mass production.

The radial engine became known as the Wasp engine, which was one of the most revolutionary engines ever developed. It was so powerful that it facilitated the commercialization of passenger air service—a cross-country journey was shortened to just two days—and a plane could carry four times the normal mail load for half the cost. The first engines were finished at the end of 1925 and in 1926 the U.S. Navy began placing engines for their engines as well. Almost immediately after, Pratt & Whitney began designing even more powerful engines.

Building United Technologies

The late 1920s were an explosive time in aircraft development. In 1929, at Pratt & Whitney Machine Tool Company, the engine company separated from the machine manufacturing company and began building an integrated aerospace company with the acquisition of the Sikorsky Aircraft Company, where millions of dollars were invested in the development of helicopter technology.

That same year, Rentschler’s companies and companies held by William Boeing were combined to form the United Aircraft and Transport Corporation, which included passenger, commercial, and military service companies; engine manufacturers; airplane body manufacturers; propeller manufacturers; and other airline parts manufacturers.

In 1934, the U.S. government decided that the United Aircraft and Transport Corporation violated anti-trust laws by holding companies along the entire spectrum of the airline business, and it was forced to break up. United Aircraft and Transport Corporation split into three companies: manufacturing west of the Mississippi River, it consolidated into the Boeing Company; manufacturing east of the Mississippi River, where it regrouped as the United Aircraft Corporation (now known as United Technologies); and turning its passenger business into United Airlines.

As president of United Aircraft, Rentschler was in charge of Pratt & Whitney, Sikorsky, Hamilton Standard, and the now-separated Chance Vought. Sikorsky’s helicopter and Hamilton Standard’s constant speed propeller were instrumental to the Allied Powers in World War II. During the war, Pratt & Whitney’s manufacturing demands exploded, stretching the limits of their new enormous campus in East Hartford, CT. The engines were becoming still more powerful, but Rentschler knew there was better technology to be perfected.

Bringing Aviation to Higher Heights

General Electric was working on the development of jet engines, but Pratt & Whitney’s development of the J57 engines in 1952 created the industry standard that was used for years. The first 10,000-lb thrust class engine in the United States, the engine’s first use was in the military’s F100 Super Sabre, which became the first aircraft to exceed the speed of sound in 1953. When the B52 Stratofortress was introduced in 1954, it carried the J57 engine. The still-more-powerful J75 was developed in 1955.

Rentschler was still president of United Aircraft when he died in 1956. His remarkable foresight and achievements in aircraft development were recognized by his admission to the Legion of Honor in 1951 for his contributions to the field. United Technologies and Pratt & Whitney continue to be worldwide leaders in aerospace technology and major assets to Hartford’s economic and cultural heritage.


1. Frederick Rentschler was an American aircraft engine designer, innovator, and entrepreneur. (Photo courtesy Wikipedia)
2. Pratt & Whitney J57 turbojet engine cutaway. (Photo courtesy Daryl Carpenter)