Rolls Royce Merlin Engine

Aviation enthusiasts are aware of the incredible story of the Rolls Royce Merlin Engine marriage with the North American P51 Mustang. But it is worth nothing that although it is tempting to dismiss in one sentence the entire process akin to a hot rodder swapping a Chevy V8 into a 1932 Ford, in reality the whole complex process required over 223,000 engineering hours, almost three times the 78,000 hours to design the original Prototype Mustang! Remember, this was in an era when design work was accomplished without cad cams, e-mail, computers, etc. but with slide rules, T-squares and 2H size pencils. It is, however, perhaps worthwhile to reflect on the circumstances that allowed this marriage to be consummated.

The New York Herald Tribune, commenting on the New Mustang said "Many have long regarded it as the best fighter plane produced in the states, but it remained for the British to discover it." If it had not been for the initial British orders it would not have been developed at all. Its full potentialities were brought out only when the British designed Rolls Royce Merlin was installed.

The gestation of the Merlin began with the famous R type engine of the Supermarine SG Schnieder Cup Seaplane racers in 1929 with the ultimate goal of developing a reliable engine suitable for military application developing 1000 horsepower. Succeed they did, with at least eleven major manifestations designed for various mission applications and/or improvements in power or reliability culminating in a tribute to the genius of the basic design with the Reno Air Race Merlin Mustangs ultimately producing over 3000 h.p. at 3800 rpm!

Besides its use in the Mustang, the Merlin was used extensively in many other British Designs. Most notably, the Spitfire, Hurricane, Mosquito, and Lancaster, as well as the Halifax, Whitely, Wellington, Barracuda, Beaufighter, Lincoln, and Battle. It even had civil application following the war in the Avro York and Douglas De-4m before the jet engine brought an end to further development.

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Consider that not only the ability to cast, forge, and machine the hundreds of parts required to assemble the Merlin was rapidly developed but that it was necessary to adapt the basic design to American Standard Fasteners, splines, gearing etc. Further, that both major and minor innovations and improvements were ongoing throughout its production life - items ranging from the two piece engine block to improved alloys and various machining techniques to continually improve the reliability of this magnificent power plant. It is, after all, one thing for an incredibly complex piece of machinery to be developed and assembled by a team of highly skilled engineers and technicians - and pampered by same under controlled conditions. But it is truly one of the great unappreciated feats of the Rolls Royce/Packard Partnership that the Merlin engine could be assembled by "the butcher, the baker, and the candlestick maker" and, not to be forgotten, scores of former housewives who became highly skilled workers in response to their country's call. The result of their efforts was then sent to perform flawlessly under life/death conditions in climate conditions ranging from the numbing cold of the skies over Europe to the blowing sands of the North African Deserts, to the steaming tropics of the South Pacific.

Although the primary thrust of the Red Tail Project is to honor the long neglected and unheralded heroism of the Tuskegee Airmen, the resurrection of another tangible example of the products of, in the words of Tom Brokaw, "The Greatest Generation" gives us an opportunity to also pay tribute to the many Black Americans who toiled in home front factories to make the exploits of the Tuskegee Airmen possible.

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