ng Woolson to the annual field day
of the National Advisory Committee for Aeronautics at Langley Field. The
700-mile trip was flown in 6-1/2 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]

[Illustration: 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.)]

[Illustration: 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-