The Hope pioneer., 1922-10-05
HELICoPTER TO
Be USED SOON
DR.. Albert F. Zahm, Expert for
the Navy, Declares 1t Is
Not an Impossibility.
TWO TYPES OFFERED TO U. S.
Experiments Are Continuing in Hope
Of Perfecting Motor That Can
Be Depended Upon to Main
tain Machine In Air.

Washington.-The helicoptor. or YER
tical rising air machine, is not an
impossibility, and, should a real use
for such type arise, successful ones
may be seen before many years, ac-
cording to Or. Albert F. Zahm, aero
nautical expert for the navy. Had
there been need for the helicopter
during the war, he said, any Of several
types could have been perfected, Of
which working models have been
flown.
Much interest has been shown of
late in reports of successful machines
of the helicopter type being perfected
in both Germany and England. How
ever, while some flights have been
made, none Of any consequence are
reported by machine equipped with
horizontal propellers or revolving
planes, designed to rise vertically from
a confined space and descend on the
same.
That the helicopter is possible Doctor
Zahm said, is proved by the German
machine, which, rising several times to
moderate heights, has carried observ-
ers, remained almost stationary while
in the air, and descended in safety.
The machine, however, has made no
extended flight, such as would prove
its dependability, but was tethered to
the ground by a mooring rope. At
times, when the motors failed, the
machine dropped, and the passengers
saved themselves only by leaping with
parachutes.
however, with the purpose of perfect
ing motor which can be depended
upon to maintain the machine without
sudden failure, the scientist explained,
for, as soon as the engine stops, the
machine cannot glide to the ground,
as does an airplane, but drops ver-
tically. In proper descent the pro-
pellers should be whirled slowly to
ease the landing.
Two Other Types Offered.
Present hopes of attaining success
full vertical flight rest mainly upon the
endeavors of Emil Berliner, Washing
ton inventor, whose experiments with
the helicopter have extended over a
long time; and Of Louis Brennan Of
London, whose newest machine is re-
ported as nearing completion. He is
working to win the $4,000 prize Of
fered by the British air ministry for
successful flight.
The helicopters upon which most ex-
perimentation has been made consist
mainly of two or more propeller screws
mounted horizontally On vertical
shaft bearing engines, fuel and pas
sengers. Equal numbers Of propeller
blades must revolve in opposite direc-
tions, that the body of the machine
may not spin like top.
Whether or not this type Of machine
is brought to actual use, Doctor Zahm
stated, at least two other types of
planes that may fly vertically have
been offered to the government. This
fact is not widely known.
One Of these, Of which Dr. Zahm OBJ.
observed experiments with working
model, was almost Identical with the
present type Of plane, except that
mounted behind the body were two
sets of air vanes, In groups, tilted at
an adjustable angle, like those Of We
netian blinds.
When the power was turned on, he
said, the "wash" of the air stream
from the propellers, pushing against
these groups Of vanes, caused the
model to rise gently vertically. The
model was held in midair by the
action, and when the power dimin-
ished it returned gently to earth. A
full-size machine of the type, he said,
would be equipped with engines Of
immense power in order to furnish
sufficient air pressure, and when
driven to a sufficient altitude the
vanes would be so adjusted that hori-
zontal motion would result. The plane
could then fly In the usual manner,
finally using the vanes again to de-
scend vertically.
Able to Rest MotionIess.
The other type offered to the army.
he said, was Of the present wing plan
equipped with three propellers. two
placed far out toward the wind ends
and with vertical rudders and ailerons
similar to those in use. The quicker
lifting power was to be gained by hav-
ing the wash Of the central propeller
act upon elevators on the tail of the
body, while the side propellers would
wash against the special ailerons on
the wing tips.
In the air, Doctor Zahm contin-
ued, this machine could maneuver ex.
actly as does the ordinary plane, cut
figures and do stunts, besides being
able to rest motionless in any desired
position-vertical with nose up, if
need be.
The best feature, he said, is that
both planes Of the new types are en-
tirely feasible and can be constructed
at any time. In fact, several Euro
pean inventors and manufacturers are