Book Reviews 10

This is like no aircraft engine book I've ever seen. Whereas most aircraft engine books are about engine design, testing and use, this one is about how the factories that built the engines were made: their conceptualization, organization, production engineering, construction, equipment, quality control and personnel. Young compares WWII Bristol, Pratt & Whitney and Curtiss-Wright single-row, medium-power two-row and high-power two-row engine production. He has apparently read everything ever published about aircraft engine production and has synthesized a grand view. The research is simply staggering; I've seen bits of what he presents in short trade publication articles, but it appears here in a single impressive volume with thousands of notes.

Both Britain and the U.S. began gearing up aircraft engine production for the upcoming war around 1936. Before then, aircraft engines had been built in relatively small batches, largely by skilled machinists using standard machine tools fitted with jigs and fixtures to speed up repetitive processes. Prior to WWII, not enough aircraft engines were built to justify custom tooling and factory automation.

With war on the horizon, both Britain and the U.S. began exploring ideas for vastly increasing production. One idea was to contract with automobile factories, but this approach was fraught with obstacles:

Aircraft engine builders didn't think automobile engine builders could work with the required precision.
Automobile engine builders faulted the aircraft engine builders for their focus on performance and not enough focus in design for manufacturability.
There were not enough skilled machinists; both countries would have to make use of unskilled and semi-skilled labor.
Aircraft engine designs were constantly changing, both to increase performance and fix problems encountered in the field; this was a problem for the typically inflexible highly-automated production lines.
Vastly more factory space would be required, as would many more highly-automated machine tools; neither the aircraft or automotive industry wanted to invest their capitol in either — tGovernments would have to foot the bill.

Britain came up with the idea of building "shadow factories" located away from the main factory; some were to build components, others complete engines. But even the new shadow factories could not be built in a way that supported continuous production — there was always a risk of being bombed and the new factories had to include blast shields to mitigate the damage done by an explosion. The British were also reluctant to invest in special-purpose automation to the extent it was used in America — they were afraid it would make model changes too difficult. However, many machine tools the British did acquire came from the U.S.

The U.S. was fortunate that it was unlikely to be bombed. This allowed the expansion of existing factories and new construction of absolutely HUGE factories filled with automatic machines on production lines that took in raw materials at one end and delivered complete, run-in engines out the other. The U.S., with its much larger automotive industry, also made heavy use of it to produce staggering numbers of engines. It also employed conveyor systems to move parts and materials, something the British could not do because of blast walls within their factories.

Young compares Bristol Mercury and Pegasus engine production to the Wright R-1820. Bristol Aeroplane shadow factories included Austin Motors, Bristol Shadow No. 2, Daimler Morot, Rootes Securities, Rover Motor and Standard Motor. Bristol Aeroplane and Austin Motors turned out complete engines; the others built components.

In the U.S., the R-1820 was of course built by Wright in Paterson, New Jersey, but Studebaker built far more complete engines in its South Bend, using components fabricated in its Chicago and Fort Wayne plants.

Young compares Bristol Hercules with Pratt & Whitney R-1830 and Wright R-2600 production. Bristol built the Daimler No. 2, Rootes No. 2, Rover No. 2, Standard No. 2 and Bristol No. 3 shadow factories, all of which produced 60,672 Hercules engines during WWII.

In the U.S., Pratt & Whitney expanded its own factory and also contracted with Buick and Chevrolet to build engines. Buick built a new plant in Melrose Park, Illinois while Chevrolet converted factory space in Buffalo, New York. Together these plants built 171,964 R-1830s during WWII.

Curtiss-Wright manufactured 84,887 R-2600s in its Paterson, New Jersey plant and a newly-built plant in Lockland, Ohio. Curtiss-Wright, which had always preferred to build in-house, struggled with meeting the promised production, especially at Lockland; they lacked the experienced production engineers and mid-level managers necessary to properly organize and manage the plant. Curtiss-Wright did employ a highly-automated production line, but seemed to never get enough training done and couldn't maintain worker morale.

The Bristol Centaurus was manufactured by Bristol at Filton and the Bristol No. 4 Shadow factory at Accington. Since it reached production later in the War, its factories were more highly automated by American machine tools. For many reasons, Bristol Centaurus production was slow achieving quantity production. Although at 2,500 hp, it was more powerful than the Wright R-3350, only 2,967 Centaurus engines were built during WWII.

The Pratt & Whitney R-2800, which completed its Type Test 1939, was manufactured by a huge new Pratt & Whitney Kansas City, Missouri plant, along with Nash-Kelvinator, Chevrolet and Ford (Detroit Michigan). During WWII, built 114,067 R-2800s. Its 13,000-plus parts presented a challenge, but its builders produced 50 successful, even innovative, versions.

The Wright R-3350, despite its troublesome gestation, was finally marginally acceptable in for Boeing B-29 power in May 1944. Built at the new Wright Wood-Ridge, New Jersey and new, largest-ever, Dodge-Chicago factories, the R-3350 enjoyed the epitome of factory and production design, despite a whopping 48,500+ design changes to the engine and its production tooling. A total of 32,240 R-3350s were produced during the war.

I cannot rave enough about how wonderful this book is. Not only has Edward Young created a masterpiece, but SAE, the publisher, has also done a superb job by presenting it in a quality hard-bound volume, with high-quality paper, three-color charts and decently-sized black and white images. This is a history book for the ages that belongs in every serious engine enthusiasts' library.

This is a monumental book in almost every respect. As the title intimates, it covers the development of nearly all American small gas turbines up until the mid-1990s. Its authors have impeccable pedigrees: Leyes is a former National Air and Space Museum (NASM) Aero Propulsion Curator; Flemings had a storied career as a NACA and NASA researcher and leader; and Atkinson, with a long career at the Naval Air Systems Command, brings an insiders’ view of military propulsion development and acquisition. Often showcasing the vast NASM engine collection, this research/writing team explores how small gas turbine manufacturers and their technologies evolved in response to opportunities and market pressures.

The quantity and quality of research is impressive, as is the breadth and depth of coverage. It is on par with Development of Aircraft Engines and Development of Fuels by Robert Schlaifer and S.D. Heron (Harvard University, 1950). Chapter 1 explains the research and writing. Funded by the NASM, Leyes and Fleming followed a methodology intended to enforce thoroughness and accuracy. The authors apparently reviewed everything published about the small gas turbine industry and almost all the engines that entailed. They then approached the manufacturers with in-depth questionnaires and requests to interview key managers, engineers and sales personnel. This reviewer thinks the fruits of these interviews are especially important since many interviewees are no longer with us. The manufacturers, realizing that NASM and the authors were producing something of lasting importance, provided virtually universal access and assistance. Armed with mountains of data, the authors each wrote chapter drafts, which they exchanged for review. This process yielded a single chapter draft that was then reviewed by the manufacturer. A concise, complete and accurate portrayal emerged of how the marketing, engineering and development challenges were addressed as the industry and manufacturers evolved and grew.

Chapter 2 defines small gas turbines based on the airframe applications they addressed:

Remotely Piloted and Unmanned Aerial Vehicles
Target Drones
Decoy, Tactical and Strategic Missiles
Helicopters
Various Military Training, Special Purpose, General Aviation and Regional Transport Aircraft

The book then explains key competitive and technical differences that set small gas turbines apart from their larger brethren. It makes the point that many of the smallest gas turbines must compete economically with traditional comparatively low-cost reciprocating engines yet still add value over the more traditional power plants. Finally, it addresses the design and manufacturing obstacles that small gas turbines present:

size impacts on gas flow
compressor and turbine clearances
cooling air requirements
manufacturing challenges such as turbine blade cooling passages
mechanical design issues, such as bearing and shaft size

Chapter 3 briefly describes initial wartime gas turbine development at Allis-Chalmers, General Electric, Lockheed, Northrop, Turbo Engineering Corporation and Westinghouse. Next, the post-war North American gas turbine pioneers including Westinghouse, Fredric Flader, Boeing and Fairchild are chronicled. Of these, only Fairchild, General Electric, and Westinghouse produced engines in quantity. Eventually all but General Electric abandoned the gas turbine business. These early companies served as training grounds for engineers and technicians whose names are later associated with successful gas turbine concerns.

Chapters 4 – 10 relate corporate histories of the major players: Allison, Garrett, General Electric, Lycoming, Pratt & Whitney Canada, Teledyne CAE and Williams International. Chapter 11 discusses the miniature and model gas turbines that arose to power small tactical missiles.

After having related the history of each major manufacturer, the book devotes Chapter 12 to trends, market forces, and technology that drove the whole industry’s evolution. Engine data tables, genealogy charts, acronyms and abbreviations largely comprise the three appendices, and the book concludes with acknowledgements and an index.

While The History of North American Small Gas Turbine Aircraft Engines is not highly technical, there is sufficient technical detail to illuminate the challenges overcome as the industry matured. There are also good discussions of the commercial and military customers, industry founders and leaders. In short, this is indeed THE history.

Almost everything about this book is a joy. Almost… If it has a flaw it is one for which I do not blame the authors, but instead lay at the feet of its publisher, the American Institute of Aeronautics and Astronautics (AIAA). The problem I have is with a format and layout that results in miniscule illustration sizes, which are a routine and glaring defect in AIAA publications that diminishes their technical value for present and future generations. One cannot properly illustrate a gas turbine cutaway or longitudinal cross section by orienting it as a portrait on a 6" x 9" page; the illustration is then only four inches wide! The AIAA technical history books will be read and referenced for the next 200 years, and every single reader will wish the illustrations were much better than they are. Two factors contribute to this: the book size and the inept layout. Why not print in 8.5" x 11" format and lay out long images, like gas turbine cutaways and line drawings, in landscape orientation? Finally, AIAA, stop constraining your authors with arbitrary page count limits; technical writing takes the number of pages necessary to properly tell the story. I know that publication and printing costs drive sale price, but most readers would willingly pay more money for books with usable illustrations. Are you listening, AIAA?

Despite the illustration limitations, this is a book that belongs in the library of every serious engine enthusiast.

Wings of War purports to tell the story of the North American P-51 Mustang from the design and development of the initial Allison-powered versions through the conspiracy/negligence of getting the Merlin-powered versions into service, and how the P-51 impacted the air war. I survived the 282 text pages, but it was a struggle. The book is a technical, factual, and chronological mess.

Unfortunately, the authors as well as editors Brent Howard and Grace Layer have sparing and diaphanous knowledge of aviation and aviation technology. Modernisms such as "... like a Jarvik-7 artificial heart ...", "... went viral..." and "... Craig Breedlove..." add nothing but confusion to the historical time frame. Technical detail is sparse, soft, and incomplete. Many players in the Mustang story, such as Lee Atwood, Ed Horkey and Irv Ashkenas, are left out. Breathless hyperbole is rampant. What exactly are "lizardlike Focke-Wulfs and stingray Messerschmitts? The authors state that automobile engines and aircraft engines are alike when they are two different engineering designs with very different requirements. The scheduled first flight date for what became the Mustang (October 26, 1940) was described as "D-Day" by the authors, 3.5 years before D-Day, the allied invasion of Europe (June 6, 1944), occurred! The terms spin, chord, stall, feather, loop, cannon, bogey, jug, rocket, jet, and bandit all have specific meanings in aviation, yet were used haphazardly and incorrectly throughout the book. The Me-163 was not “the first rocket powered plane ever to fly”. B-17's with a 17,600-pound bomb load? B-17’s flying from England to Berlin with a 9,000-pound bomb load? In describing the P-51D Shuttle missions, “They took almost the whole runway to get aloft, their heavy drop tanks weighed 108 pounds”. I can only assume they meant the 108 gallon paper drop tank which when loaded, weighed +/- 800 pounds each. The photograph chosen to depict the German Bf-109 is in fact a Spanish-built, post-WWII HA-1112 “Buchon” that, ironically, used the Merlin engine instead of the wartime Daimler-Benz. A single paragraph was devoted to P-51 operations in the Pacific theater. The book states P-51's were "... a superb warrior against the MiG-15's in Korea.” What? And as a final disappointment, the back cover graphics showing a front and side view of, I presume, a P-51D, appear to be the inaccurate renderings of a school boy.

In between, the authors accredit and draw heavily from previously published narratives dealing with the European air war, which were welcome. However, I found the descriptions of the life and times of Thomas Hitchcock and Donald Blakeslee to be the only content of merit.

Archibald Russell (1904-1995) was PhD aeronautic engineer whose career spanned the post-WWI era to the dawn of the Concorde. He joined Bristol in 1925 and retired from the amalgamated British Aerospace Company in 1969. In between his amazing career included stress analysis work on Bristol biplanes, stewardship of Bristol as chief designer, and carrying through the Brabazon, Brittania, Bristol Freighter, multiple Bristol studies and proposals on medium-range jet transport aircraft, and ultimately the Concorde. Russell is a gifted and directed writer who is unafraid to recognize and explain the successes and mistakes of his craft, company, and country. Among dozens of interesting stories and histories, he deftly reveals the early days of the Anglo-French Concorde project, weighing in on the shifting design goals, personalities, politics, economies, and choreography of the British, French, American, and Russians players of that time. It is a pleasure to read aeronautical history recorded by a person who experienced the projects in real time. I did not find a boring section in the whole book. Highly recommended.

Two years before the start of WWII in Europe, Frank Whittle was the first man to design, build, and run a turbojet engine intended to power aircraft, the experimental "Whittle Unit First Model". This opened the jet age on April 12, 1937. Over the next few years, Whittle refined his turbojet producing more experimental Whittle Units until a model evolved that was ready to fly. The Power Jets W.1 took flight in a Gloster E28/39 on May 15, 1941, and the prototype Gloster Meteor twin jet fighter flew on March 5, 1943 using an improved Power Jets W.2.

By April 1944, Power Jets Limited, founded by Whittle in January of 1936, was nationalized, essentially ending Whittle’s direct involvement in jet engine development. Ongoing amongst these milestones were technical challenges, unending British ministerial intrigue, maneuvering for resources, staggeringly ineffectual communication, mental and physical exhaustion, and corporate deceit, all told by the man that bore the yoke of these struggles.

While there is sufficient technical information and anecdotes to hold the interest of the mechanically inclined, the majority of the book is the author explaining in significant and documented detail, the trials and tribulations of navigating the Byzantine world of government and military ministries, corporate titans, and corporate sub-titans, all during war time. It is not a happy story, but I believe it to be an honest story told first hand by the pioneer engineer, flight-rated military officer, and persevering genius that was Sir Frank Whittle.

Several excellent books about Whittle and the dawn of the turbo jet have been published over the years. But if you can find this book, written not too distant from the storied events, it provides the foundation to understand the many facets of the Whittle story told in the books that followed it.

Air racers and restorers of Merlin-powered aircraft often reference the scarcity, strength, and value of “transport Merlin” parts, particularly heads and banks. The Canadair North Star is the transport that used the 620 and 720 series Merlin engines, and thus the reason for my initial interest in the highly modified and pressurized Canadian stepson of the Douglas DC-4.

Author Milberry starts with the post-war need for transports to span the wilds of Canada with speed and efficiency above the weather. He extensively documents the details how Canadair investigated several aircraft to fill this role, and decided upon licensing and highly modifying the DC-4 to meet its needs. Excellent technical information is presented in text and tables explaining the logic and expected economies of the North Star as well as the urgency, costs, and controversy of such an ambitious endeavor. The pilots, business men, politicians, and aeronautical engineers that formed the program are well and interestingly chronicled. It is a masterful blend of technical and first-person story telling.

The aircraft was first flown in July of 1946 and served with Trans-Canada Airways (TCA), BOAC as the “Argonaut”, Canadian Pacific Airways, the Royal Canadian Air Force, and several other operators. In addition to Canadian routes, the North Star flew across the Atlantic, to the Orient, the Caribbean, and Africa.

The Merlins were run hard, and there is much discussion in the book on dealing with the mechanical issues of the transport Merlin, Rolls-Royce warranties, pressurization, the unrelenting noise of the engines, and operational mishaps big and small. There are also wonderful, detailed crew descriptions of long distance flights to exotic locales and the complexities of such operations in the late 1940s/early 1950s.

The writing is excellent, the book heavily loaded with high quality black & white photographs, and there is a wealth of technical and operational detail not often found books of this type. In addition, there is a section of spectacular color photographs of the North Star in various liveries which is only outdone by a gallery of nine outstanding color paintings of the aircraft. And to top it off, there is a 24 x 24 inch folded technical drawing of the TCA DC-4M tucked in a pocket of the rear hardback cover.

I never thought I’d be interested in transport aircraft, but this book changed all that. It is widely available through book resellers and I found my excellent copy with dust jacket for $20.

Turbulent Journey is a biography/autobiography about the German Decher family, Siegfried, Else, Reiner and Ulrich as they navigated WWII and its aftermath. Siegfried was an engineer who worked for Junkers in Dessau on the Jumo 004 jet engine, which powered the Messerschmidt Me 262. Siegfried designed the engine control system and received patents for some engine control elements.

Family life in wartime Germany was initially tranquil, but as the war progressed, the German army was driven from Russia and Allied bombers reached deeper into Germany, things became progressively more dire. When the war ended the Decher family decided to emigrate to America under Operation Paperclip, which swept up a about 1,600 German engineers and scientists. As invading Russians moved west, the U.S. Army began moving the family southwest just a week before the Russians arrived, but their truck was involved in an accident, which fractured Ulrich’s skull. Siegfried continued west while the rest of the family remained behind during Ulrich’s convalescence, hiding from the Russians. The family was reunited, but the Americans reneged on their offer of asylum.

Housing and food were scarce, but a reprieve came when Siegfried was offered a position at what was to become SNECMA (now Safran), resulting in a move to France. Ultimately, some of Siegfried’s Junkers colleagues who had made it to America arranged for him to work at the newly-formed AVCO gas turbine division. The Dechers finally made it to America in early 1954. Renier obtained a doctorate in aeronautical engineering and became professor emeritus at the University of Washington.

Turbulent Journey is a very personal account of a child growing up in and ultimately leaving wartime Germany. It relates many poignant stories about his family and their friends. Gas turbine technical issues are discussed only to the extent that they amplify the central personal theme.

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