ill come slowly and will not be a solid injection engine."

Henry M. Mullinnix (former chief of powerplant section, Navy Bureau of
Aeronautics):

The advantages of compression-ignition, including reduced fire
hazard, more efficient cycle, elimination of electrical apparatus
and hence of radio interference, elimination of carburetion
problems, and other benefits less evident, would seem to outweigh
the difficulties encountered in metering and injecting minute
quantities of fuel at the proper instant. Although the Diesel
engine suffers upon comparison with the Otto cycle engine in
flexibility there seems to be a definite field for employment of
Diesels and a gradual extension of their use may be predicted.

John H. Geisse (chief engineer, Comet Engine Corporation): "I am firmly
convinced that the Diesel engine in the future will not only maintain
the advantages of Diesel engines as they are now known, but will also be
lighter in pounds per horsepower than the present Otto engines."

Lt. Cdr. C. G. McCord (U.S. Navy, Naval Aircraft Factory): "The use of
compression ignition in due time appears to be assured; but increase in
weights above those of present Otto cycle engines, to insure
reliability, must be expected."

L. M. Woolson (aeronautical engineer, Packard Motor Car Company): "There
is no question that the compression ignition aircraft engine will in
time offer severe competition to the gasoline engine. There are,
however, many basic problems to be solved for the solution of which
there exists no precedent."

N. N. Tilley (chief engineer, Kinner Airplane and Motor Corp.):

Considerable development of the compression ignition type of engine
for aircraft will be required before it is commonly available. It
is believed that the weight per horsepower must be equal to, or
less than, that of the present type of engines, in order to
interest the public, since rapid take-off, rate of climb, and speed
are desired, rather than low fuel consumption or high mileage. Most
flights are of few hours duration. It is believed that flights must
be of over five or six hours duration in order to show any
advantage of Diesel engines (with low fuel consumption) if
appreciably heavier than present engines. Also the difference
between Otto cycle and Diesel becomes slight as the compression
ratios come closer together.

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