Question: Who created the engines used in the aircraft of the aviator who completed the first solo transatlantic flight?

Context articles: North Atlantic Tracks
George E. A. Hallett
George Herbert Scott
Frederick Rentschler
Lindbergh Boom
Stationary steam engine
Curtiss NC-4
Hughes H-4 Hercules
Charles Lindbergh
Douglas Corrigan

North Atlantic Tracks, officially titled the North Atlantic Organised Track System (NAT-OTS), is a structured set of transatlantic flight routes that stretch from the northeast of North America to western Europe across the Atlantic Ocean.
 They ensure aircraft are separated over the ocean, where there is little radar coverage.
 These heavily traveled routes are used by aircraft traveling between North America and Europe, flying between the altitudes of 29,000 and 41,000 feet inclusive.
 Entrance and movement along these tracks is controlled by special Oceanic Control Centres air traffic controllers to maintain separation between airplanes.
 The primary purpose of these routes is to allow Air Traffic Control to effectively separate the aircraft.
 Because of the volume of NAT traffic, allowing aircraft to choose their own co-ordinates would make the ATC task far more complex.
 They are aligned in such a way as to minimize any head winds and maximize tail winds impact on the aircraft.
 This results in much more efficiency by reducing fuel burn and flight time.
 To make such efficiencies possible, the routes are created twice daily to take account of the shifting of the winds aloft and the principal traffic flow, eastward in North America evening and westward twelve hours later.
Colonel George Eustace Amyot Hallett (May 9, 1890 – June 2, 1982) was a pioneer aviator.
 He and John Cyril Porte planned to make the first transatlantic flight.
 They were going to use a flying boat commissioned by Rodman Wanamaker, but were prevented by the start of World War I.
 In 1919 the transatlantic flight of Alcock and Brown set the record that they hoped to achieve.
Major George Herbert "Lucky Breeze" Scott, CBE, AFC, (25 May 1888 – 5 October 1930) was a noted British airship pilot and engineer.
 After serving in the Royal Naval Air Service and Royal Air Force during World War I, Scott went on to command the airship R34 on its return Atlantic crossing in 1919, which marked the first transatlantic flight by an airship and the first east–west transatlantic flight by an aircraft of any kind.
 Subsequently, he worked at the Royal Airship Works in connection with the Imperial Airship Scheme and took part in a second return Atlantic crossing, this time by the R100, in 1930.
 He was killed later in the year (along with 47 other people) aboard the R100's near-sister, the R101, when it crashed in northern France during a flight to India.
Frederick Brant Rentschler (November 8, 1887 – April 25, 1956) was an American aircraft engine designer, aviation engineer, industrialist, and the founder of Pratt & Whitney Aircraft.
 Rentschler created and manufactured many revolutionary aircraft engines, including those used in the aircraft of Charles Lindbergh, Amelia Earhart and James Doolittle.
 He is also a co-founder of United Aircraft and Transport Corporation, the predecessor of United Technologies Corporation.
The Lindbergh Boom (1927–1929) is a period of rapid interest in aviation following the awarding of the Orteig Prize to Charles Lindbergh for his 1927 non-stop solo transatlantic flight in the Spirit of St. Louis.
 The Lindbergh Boom occurred during the interwar period between World War I and World War II, where aviation development was fueled by commercial interests rather than wartime necessity.
 During this period, dozens of companies were formed to create airlines, and aircraft for a new age in aviation.
 Many of the fledgling companies funded by stock went under as quick as they started as the stock that capitalized them plummeted in value following the Wall Street Crash of 1929.
 The Great Depression dried up the market for new aircraft, causing many aircraft companies to go into bankruptcy or get consolidated by larger entities.
 Air racing, record attempts, and barnstorming remained popular, as aviators tried to recapture the prizes and publicity of Lindbergh's Transatlantic flight.
Stationary steam engines are fixed steam engines used for pumping or driving mills and factories, and for power generation.
 They are distinct from locomotive engines used on railways, traction engines for heavy steam haulage on roads, steam cars (and other motor vehicles), agricultural engines used for ploughing or threshing, marine engines, and the steam turbines used as the mechanism of power generation for most nuclear power plants.
The NC-4 was a Curtiss NC flying boat which was designed by Glenn Curtiss and his team, and manufactured by Curtiss Aeroplane and Motor Company.
 In May 1919, the NC-4 became the first aircraft to fly across the Atlantic Ocean, starting in New York State and making the crossing as far as Lisbon, Portugal, in 19 days.
 This included time for stops of numerous repairs and for crewmen's rest, with stops along the way in Massachusetts, Nova Scotia (on the mainland), Newfoundland, and twice in the Azores Islands.
 Then its flight from the Azores to Lisbon completed the first transatlantic flight between North America and Europe, and two more flights from Lisbon to northwestern Spain to Plymouth, England, completed the first flight between North America and Great Britain.
The Hughes H-4 Hercules (also known as the Spruce Goose; registration NX37602) is a prototype strategic airlift flying boat designed and built by the Hughes Aircraft Company.
 Intended as a transatlantic flight transport for use during World War II, it was not completed in time to be used in the war.
 The aircraft made only one brief flight on November 2, 1947, and the project never advanced beyond the single example produced.
 Built from wood because of wartime restrictions on the use of aluminum and concerns about weight, it was nicknamed by critics the "Spruce Goose", although it was made almost entirely of birch.
 The Hercules is the largest flying boat ever built, and it has the largest wingspan of any aircraft that has ever flown.
 It remains in good condition and is on display at the Evergreen Aviation & Space Museum in McMinnville, Oregon, United States.
Charles Augustus Lindbergh (February 4, 1902 – August 26, 1974), nicknamed Slim, Lucky Lindy, and The Lone Eagle, was an American aviator, military officer, author, inventor, explorer, and environmental activist.
 At age 25 in 1927, he went from obscurity as a U.S. Air Mail pilot to instantaneous world fame by making his Orteig Prizewinning nonstop flight from Long Island, New York, to Paris.
 He covered the 33 ⁄ -hour, 3,600 smi alone in a single-engine purpose-built Ryan monoplane, "Spirit of St. Louis".
 This was the first solo transatlantic flight and the first non-stop flight between North America and mainland Europe.
 Lindbergh was an officer in the U.S. Army Air Corps Reserve, and he received the United States' highest military decoration, the Medal of Honor, for the feat.
Douglas Corrigan (January 22, 1907 – December 9, 1995) was an American aviator born in Galveston, Texas.
 He was nicknamed "Wrong Way" in 1938.
 After a transcontinental flight from Long Beach, California, to New York City, he flew from Floyd Bennett Field in Brooklyn, New York, to Ireland, though his flight plan was filed to return to Long Beach.
 He claimed his unauthorized flight was due to a navigational error, caused by heavy cloud cover that obscured landmarks and low-light conditions, causing him to misread his compass.
 However, he was a skilled aircraft mechanic (he was one of the builders of Charles Lindbergh's "Spirit of St. Louis") and had made several modifications to his own plane, preparing it for his transatlantic flight.
 He had been denied permission to make a nonstop flight from New York to Ireland, and his "navigational error" was seen as deliberate.
 Nevertheless, he never publicly admitted to having flown to Ireland intentionally.