Pratt & Whitney Aircraft's J-57 jet is the first production en-

gine in the 10,000-pound thrust class. An entire generation

of aircraft, both fighters and bombers, has been built around

its tremendous power and unparalleled fuel economy.

The New Margin in Power AT the end of 1953, Admiral De-

Witt C. Ramsey ( retired ), pres- ident of the Aircraft Industries

Association, listed the "outstanding accomplishments of American built aviation products" during the year. The five aviation highlights of 1953 that he specified included these three:

1. Volume production of a 10.000- pound thrust engine.

2. Several aircraft exceeded 700 miles per hour in attempts to set new official world's speed records, with 751.98 miles per hour being the present official speed record.

3. Deliveries of the first super- sonic combat plane to go into volume production.

All of these accomplishments are

related directly to Pratt & Whitney Aircraft's new turbojet engine, the J-57 the first engine in aviation history to be officially rated in the 10.000-pound thrust class. Admiral Ramsey did not give times and places or names of engines and airplanes that figured in aviation's top achieve- ments of the year. If he had. the de- tails would have specified that the J-57. after an extremely large quantity of prototype models had been built and delivered, has been in production at East Hartford. Conn., since Febru- ary of 1953. Production of the engine for the Air Force has climbed steadily since that time and will continue to increase through 1954. J-57 produc- tion will be further augmented in 1954 by Ford, making the P&WA engine under "no fee" license at the

automobile company's Chicago plant.

The J-57 models include an engine to which an afterburner has been added to provide a high percentage of increased power for use of jet fighter aircraft. It is this afterburner version of the J-57 which powered a North American F-100 Super Sabre Air Force fighter to a new world's speed record of within a small frac- tion of 755 miles an hour. The record flights were made October 29 by Lieut. Col. F. K. I Pete) Everest, Air Force test pilot, over a 9.3-mile straightaway course at Salton Sea.

The F-100, successor to the F-86 Sabre which outfought the Russian- built Mig in Korea, was the first supersonic combat plane to go into volume production. The first produc-

Wright Parkins, P&WA engineering manager; L. S. Hobbs, UAC vice president, and W.P. Gwinn, P&WA general manager, with ihe J-57.

i

V

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The seven Double Wasp engines in ihe background, each capable of 2,400 hp, approximate the mini- mum piston horsepower that would be required to duplicate the power of the J-57 in the foreground.

President Eisenhower presented the Collier award to L. S. Hobbs at dinner in Washington.

tion Super Sabre rolled out of North American's Los Angeles plant on October 20. Earlier, the first proto- type Super Sabre had demonstrated on its very first test aloft that it could easily exceed the speed of sound (Mach 1) in level flight. In the words of Dr. Hugh L. Dryden, director of the National Advisory Committee for Aeronautics, the J-57 "made possible supersonic speed in level flight." After the first F-100 flights last May, George Welch, North American test pilot, said the airplane was the "best I've wrung out in 13 years of flying."

The greatest distinction was re- flected on the J-57 during the last year by the award of the Collier

Trophy to Leonard S. Hobbs, vice- president for engineering of United Aircraft Corporation, for conceiving the engine and guiding it through to production. The award is given an- nually for "the greatest achievement in aviation in America, the value of which has been demonstrated by actual use during the preceding year." It was the first time in 21 years the famous trophy has been awarded for the development of an engine. Hobbs received the trophy from President Eisenhower December 17, the fiftieth anniversary of powered flight.

Hobbs, a native of Carbon, Wyom- ing, spent his boyhood in Texas and was graduated from Texas Agricul-

tural and Mechanical College. He in- terrupted his postgraduate studies at Kansas State College to serve in World War I as an engineering officer with the famed 42nd (Rainbow) Division. After leaving the service he special- ized in aircraft carburetor develop- ment. He joined Pratt & Whitney Air- craft in 1927 as a research engineer. In 1935 he was named engineering manager of Pratt & Whitney Aircraft, and subsequently directed all of the division's wartime powerplant devel- opments.

"No one man can claim credit for a project such as the J-57," says Hobbs. "It took the combined efforts of a great many people: Andy Will- goos who headed up the early research work; Wright Parkins, Pratt & Whit- ney Aircraft engineering manager, who took over after Andy's death, and 1,500 P&WA engineers." The Collier Trophy was awarded to Hobbs as captain of the team.

Words of Acceptance In accepting the Collier Trophy

from President Eisenhower at the

Aero Club dinner in Washington,

D. C, December 17th, Leonard S.

Hobbs, vice-president in charge of

engineering at United Aircraft said:

"I deeply appreciate this award

and the high honor of its receipt

at your hands. I am profoundly

grateful to all the individuals and

organizations responsible for it,

including in a most major way the

United States Air Force, whose

support of the development from its inception has never varied. My

gratitude in the greater part is for the many, many individuals of my

organization who are the real re- cipients of the award and who now

have this recognition of a contri-

bution to the country and to avia- tion."

The J-57 has been flying since March. 1951, when it powered a B-50 bomber converted into a flying test bed. On April 15. 1952. eight proto- type J-57 engines lifted the Air Force's giant Boeing B-52 intercon- tinental jet into the air at Seattle, Washington. Last July, after more than a year of rigorous flight test-

ing of the jet bomber. Boeing engi- neers pronounced the J-57 "the best brand new engine we've had in any experimental airplane." The B-52. known as the Stratofortress. has been ordered into production by the Air Force. It is expected to be one of the most effective weapons in the nations arsenal of air power. Defense Depart- ment officials have hinted at the speeds achieved by the B-52 by de- scribing it as faster than the smaller B-47 jet bomber, which is in the 600- mile-an-hour class.

In announcing the official rating of the J-57 as being "in the 10.000- pound thrust class," the Air Force said last November that the engine "has the lowest specific fuel con- sumption of any turbojet engine presently in production for the Air Force." The J-57 had successfully completed the exacting military 150- hour test. The Air Force revealed that the Pratt & Whitney Aircraft de- sign of "the axial-flow engine in- corporates an arrangement of dual compressors in line which gives the engine a high compression ratio and an unusual fuel economy."

First Dual-Compressor Jet

The fuel economy of the J-57 en- gine is as important a feature as its high thrust. These advantages were gained through the basic dual-com- pressor design, which was selected and then made to operate properly in the new engine. The separate compressor units each rotate inde- pendently on concentric shafts turned by different turbines. The arrange- ment has been described by Wright Parkins, engineering manager of Pratt & Whitney Aircraft, as "two engines in one." Each of the com- pressor-turbine units works independ-

Admiral DeWitt C. Ramsey

ently of the other, allowing the en- gine to start quickly and easily and to operate efficiently over a wide speed area. This enables the engine to gain added range from its low rate of fuel consumption and greater power from its high compression ratio.

The J-57 was the first in its field with the dual-compressor system. Be- fore the work on the specific J-57 project began in May, 1949, all turbo- jet engines in operation had single- compressor units, whether axial-flow or centrifugal-flow in design.

It took more than three years to develop the first workable J-57. Dur- ing that time more than 4,000.000 individual complex problems had to be solved. To accomplish these solu- tions required more than 300 hours of calculation by electronic com- puters and 14.000 man-hours.

Selected for Top Planes

The way in which the I nited States has appraised the performance of the J-57 is shown in the selection of the engine for an ever widening group of new high-performance aircraft. In ad-

dition to the B-52 and F-100. the Air Force's supersonic delta-winged Con- vair F-102 fighter has already flown with the J-57. The engine is slated for the Air Force's McDonnell F-101 Voodoo in the "century series." Two Navy production aircraft, one a two- engined bomber and the other a single-engined carrier-based fighter, are also scheduled to be powered by the J-57. The bomber, the Douglas A3D, has already flown with two J-57s, and the fighter, the Douglas F4D Skvray, is scheduled to fly with the powerplant this year. Other mili- tary aircraft, which cannot yet be specified, are expected to take the J-57. Thus its application already ranges from intercontinental bomber aircraft to supersonic fighters, and new airplanes embodying the very latest theories are being designed around it.

Capable of Greater Growth

With the J-57 in production, new horizons have been o