The historic first flight took place on September 19, 1928, at the Packard proving grounds in Utica, Michigan, just a year and a month from the day Dorner agreed to join the Packard team. Woolson and Walter E. Lees, Packard’s chief test pilot, used a Stinson SM-1DX “Detroiter.” The flight was so successful, and later tests were so encouraging, that Packard built a $650,000 plant during the first half of 1929 solely for the production of its diesel engine. The factory was designed to employ more than 600 men, and 500 engines a month were to have been manufactured by July 1929.[4]

Figure 3.—Alvan Macauley (left), President of the Packard Motor Car Co. and Col. Charles A. Lindbergh with the original Packard diesel-powered Stinson “Detroiter” in the background, 1929. (Smithsonian photo A48319D.)

The engine’s first cross-country flight was accomplished on May 13, 1929, when Lees flew the Stinson SM-1DX “Detroiter” from Detroit, Michigan, to Norfolk, Virginia, carrying Woolson to the annual field day of the National Advisory Committee for Aeronautics at Langley Field. The 700-mile trip was flown in 6½ hours, and the cost of the fuel consumed was $4.68. Had the airplane been powered with a comparable gasoline engine, the fuel cost would have been about 5 times as great.[5] On March 9, 1930, using the same airplane and engine, Lees and Woolson flew from Detroit, Michigan, to Miami, Florida, a distance of 1100 miles in 10 hours and 15 minutes with a fuel cost of $8.50. The production engine, slightly refined from the original, received the first approved type certificate issued for any diesel aircraft engine on March 6, 1930. The Department of Commerce granted certificate no. 43 after the Packard Company had ground- and flight-tested this type of engine for approximately 338,000 hp hr, or about 1500 hr of operation.[6]

Figure 4.—Dipl. Ing. Hermann I. A. Dorner, 1930.
German diesel engine designer, was responsible
for the Packard DR-980 aircraft engine.
(Smithsonian photo A48645.)		 Figure 5.—Capt. Lionel M. Woolson, 1931.
Chief Aeronautical Engineer, Packard Motor Car Co.
Designer of Packard DR-980 diesel engine.
(Smithsonian photo A48645A.)

One of the early production versions powered a Bellanca “Pacemaker” which was piloted by Lees and his assistant Frederic A. Brossy to a world’s nonrefueling heavier-than-air duration record. The flight lasted for 84 hours, 33 minutes from May 25 through 28, 1931, over Jacksonville, Florida. This event was so important that it was the basis of the following editorial, published in the July 1931 issue of Aviation,[7] which summarizes so well the progress made by the diesel engine over a 3-year period and the hope held for its future:

A RECORD CROSSES THE ATLANTIC—The Diesel engine took its first step toward acceptance as a powerplant for heavier-than-air craft when, in the summer of 1928, a diesel-powered machine first flew. The second step was made at the 1930 Detroit show, when the engine went on commercial sale. The third was accomplished last month, when a plane with a compression-ignition engine using furnace oil as a fuel circled over the beaches around Jacksonville for 84 hours and inscribed its performance upon the books as a world’s record—the longest flight ever made without intermediate refueling.

With the passing of the refueling-duration excitement, and with the apparent decision to allow that record to stand permanently at its present level, trials for straight time in the air without replenishment of supplies begin to regain a proper degree of appreciation. No other record, unless it be some of those for speed with substantial dead loads, is of such importance as the non-stop distance and duration marks. No other has such bearing upon precisely those qualities of aerodynamic efficiency, fuel economy, and reliability of airplane and powerplant that most affect commercial usefulness. It is more than three years since the duration record left American shores, and it has been more than doubled in that time. Its return is very welcome.

It is doubly welcome for being made with a fundamentally new type of engine. The diesel principle is not a commercial monopoly. It is open to anyone. Already two different designs in America, and one or two in Europe, have been in the air. For certain purposes, at least, it seems reasonable to expect that its special advantages will bring it into widespread use. Every practical demonstration of the progress of the diesel toward realizing its theoretical possibilities in the air as it has realized them on the land and at sea is a bit of progress toward better and more economical commercial flying, and so benefits the whole industry. The fourth, and next, main element in the demonstration will be provided when diesels go into regular service on some well-known transport line as standard equipment, and the accumulation of data on performance under normal service conditions begins. We believe that that will happen before the end of 1932.

Many men, from Dr. Rudolf Diesel to Walter Lees and Frederic Brossy, have had direct or indirect hands in the making of this record. The greatest of all contributions was that of Lionel M. Woolson, who created the engine and flew with it in every test and brought it through its early troubles to the point of readiness for the commercial market. The flight that lasted four days and three nights is his memorial, quite as much as is the bronze plaque unveiled last April in the Detroit show hangar.