Evening star., 1929-10-06
AVIATION
BY JOSEPH S. EDGERTON.

forward fight, while the nth,
astern, may be used either for for
ward or reverse movement. AS
a reverse motor, it acts as a pow
erful brake and may be used for
control in coming into a field. 1t
is expected that the five motors
will give a maximum speed OF 70
to 80 miles per hour, though crit
les in England claim that a cruis-
ing speed of IS miles per hour is
as much as may be expected.
The R-101, though it's capacity
is much greater than that of the
Graf Zeppelin, is shorter than the
German dirigible. She is 1872 feet
long, as against the Crafts 776
feet. The Britisher'S diameter,
however, is 131 feet, as against
100 feet for the Graf Zeppelin,
and her lifting gas capacity is
4,980,000 cubic feet, as compared
with the Graf'S 100000 cubic
feet.
The lifting capacity of the R-101
is estimated at 152 tons, and tank
age is provided for 20 tons of fuel
oil. The oil will be carried in SO
main tanks, attached to the
framework inside the envelope
There also are II compenSating
tanks which may be filled when
there is not full passenger load
aboard. Quick dumping facilities
are provided for all tanks in case
of emergency.
Miles of Tubing.
! The lightest of materials is used
, in construction of the ship
TWenty-seven miles of metal tub
ing, chiefly of stainless steel, solid
drawn, have been used in the
framework. Duralumin and alum
mum are used wherever possible
even for cooking and lighting
equipment. BalSa wood fittings
are used in the cabins. The walls
Of the passenger cabins are OF
specially treated canvas and fnoSt
of the furniture is of rattan and
reed.
There are said to be 10000 tie
rods, $4,000 nuts and bolts, 100000
rivets, $1,000 shackles and II miles
of bracing cable incorporated in
the framework. The envelope
consists of 225,O00 square feet OF
fabric.
While the ship is in the air look
outs will be posted at all times at
crows nests" in the bow, on top
of the bag and in the extreme
stern, in addition to the crew al
ways on duty in the control car
From these lookout points the
navigation officer may shoot the
sun" or make other weather OF
navigation observations.
Results AnxiOusly Awaited.
Great Britain is watching the
results of the R-101 tests hopeful
ly. It has been planned to estab-
liSh airShip lines between England
and the far-flung British posses.
sions, and the R-101 and a sistel
ship, the R-100, now nearing COM
pletion, were planned as the first
units of the system.
It has been estimated that diri.
gible would connect England anC
Egypt in two and a half days, a;
compared with six days by steam
ship; England and Bombay, India
in five days, as against the present
IS; England and Perth, Australia
in IL days instead of %, and Eng
land and Canada in two and g
half days as against six.
The two British airships promise
to add much to the knowledge OF
airship construction and opera
ton, which has been slowly ano
laboriouSly acquired. Though the
airship preceded the airplane by
many years, it has not kept pace
with heavier-than-air develop
ment for very apparent reasons.
For efficiency the airShip must
depend upon size. From the start
the units of a successful airShip
line must be of great size and car
rying capacity. This means tre-
mendous initial outlays for equip
ment, training of crews and con-
struction of hangers and termi-
mails.
Those who have sponsored the
British ships are confident that
profits can be made from the
operation of commercial dirigibles
and hope to prove their point with
the R-100 and R-101. Should this
prove to be the case the next few
years should witness considerable
a ctiUitxy in tho 6iri1ih1o fold