In 1938, the Pennsylvania Railroad introduced the world's largest steam locomotive, the S-1 and distinctive round-ended observation cars for its Broadway Limited. They were designed by Raymond Loewy in collaboration with Paul Philippe Cret, head of Architecture at the University of Pennsylvania. The S-1, with its bullet-nose, projecting headlight and horizontal chrome strips extending the length of the engine, was an improved version of the K4S Loewy designed for PRR in 1936. The S-1, capable of 100 mph speed, was a feature attraction at the 1939 World's Fair. Only one S-1 was ever built, but like most of Loewy's work for PRR, served as an incredible PRR promotional piece, and not incidentally, identified Loewy forever with the streamlined train. Loewy also designed the T-1 steam locomotive in for PRR, a later version of the S-1 with a wedge-shaped nose. Fifty were built, but they were soon discarded as PRR switched to diesel locomotives. Raymond Loewy (1893-1986), probably the most widely known US industrial designer, was born in Paris. He studied engineering 1910-1914, served in the French army in World War I and arrived in US in 1919. He worked as a fashion illustrator for Vogue and Harper’s Bazaar, and designed costumes for Florenz Ziegfeld. Opening his own office in 1929, his first product assignment was a duplicating machine for Gestetner, which was featured in a 1934 Fortune magazine article. Major clients included Pennsylvania Railroad, Coca-Cola, International Harvester, Studebaker, and NASA. He was on the cover of Time magazine in 1949. He wrote "Never Leave Well Enough Alone" in 1951, and "Industrial Design" in 1979. By 1960, he had a staff of 180. His US office filed for bankruptcy in 1977, closing US offices but keeping those in Europe. On the same day that PRR introduced the S-1, New York Central Railroad introduced 10 new streamliner J-3 steam engines and cars designed by Henry Dreyfuss for its Twentieth Century Limited New-York-Chicago run.

The Douglas DC-3, an airliner which carried 21 passengers, was first flown in 1935. It was designed and patented by chief engineer James H. (Dutch) Kindelberger and designer Arthur E. Raymond (1900-1999) to compete with the Boeing B-247. The B-247, which made its first flight in 1933, was the first all-metal monoplane transport, based on an earlier B-9 bomber designed by Claire Egtvedt. It had been ordered by United Air Lines, had twin engines and a retractable landing gear, carried 10 passengers in a heated, sound-proof cabin, and was able to cross the country in 20 hours, cruising at 155 mph. Later versions of this design evolved into the B-17 Flying Fortress of World War II fame. A single prototype of the competing twin- engine Douglas 12-seat DC-1, flew in 1933, and the first production version, the DC-2, began scheduled service for Transcontinental & Western Air (later TWA) on the Newark-Chicago run in 1934, carrying 14 passengers. Commercial success of the DC-2 initiated the 1934 development of the DC-3 which went into service for American Airlines in 1936 and which became the first to make commercial air travel profitable and realistic. By 1942, 90% of airliners in use were DC-3s. 11,000 were eventually produced. During WW II, the DC-3 was called the Dakota by the British, the C-47 Skytrains by the Air Transport Command, R-4Ds by the Navy, and the Gooney Bird by most troops. Though production ceased in 1946, two thousand DC-3s were still in service in the late 1980s. Donald W. Douglas, an aircraft designer, founded the company in 1920, with most of its work for the US Army Air Corps. In 1924, a Douglas US Army plane, the Chicago, piloted by Lt. L.H. Smith, completed the first flight around the world in 351 hours flying time. Commercial transatlantic flights did not begin until 1939, when the flight took 26.5 hours.

The Boeing 747 "jumbo-jet" made its first public flight in 1969. It carried 342-490 passengers and was 231 feet long. Interiors were designed by Walter Dorwin Teague Associates (WDTA). It went into transatlantic service in early 1970 for Pan American Airlines. The ancestry of the 747 started with a military version (C-97) of the B-29 (which dropped the atomic bombs on Japan in 1945). In 1946, a commercial version of the C-97 became the Stratocruiser, the first post-war luxury-class transatlantic airliner, which carried 55 to 100 passengers. Interiors were designed by Frank Del Guidice of WDTA. This was probably the first commercial plane with interiors by an industrial design office, and for this purpose, WDTA established a permanent design office at the Boeing plant in Seattle. The Stratocruiser was followed by a modification of the Boeing KC-135 Air Force tanker jet developed in 1955 for Pan Am commercial use. Again, Del Guidice and WDTA designed interiors and livery, as well as some exterior contours. A later version of this in 1958 became known as the Boeing 707, the first transatlantic commercial jet. It had four engines and seated 147-181 passengers. WDTA again did the interiors, but Henry Dreyfuss Associates developed those for American Airlines, and Raymond Loewy whipped up interiors and livery for the famous Air Force 1version in 1963, first used by President John Kennedy. The two-engined Boeing 737 debuted in 1967 with a capacity of 108-189, and became the best-selling jetliner in aviation history. Interiors, of course, were by WDTA. The 747 came next in 1969. In 1982, the 767 and the fuel-efficient 757 appeared. The latter seated 194-231. WDTA interiors on both. In 1988, a later model of the 747 (747-400) seated 420-566.