Evening star. [volume] (Washington, D.C.) 1854-1972, 1929-11-29

side of the Pole, which, for Nractical
purposes, is Suf1cient.
If flag is dropped at the approx
mate position of the Pole and from one
end of this flight at right angles to the
former course q wide circle is made
about the flag, the chances that the
plane will pass very close to the Pole are
again increased.
Plotting the Return Course.
But how to get home? All the rail-
road trackS"sare to the north Time has
relatively ceased. Which track to take?
There are two ways of determining the
planes position.
The sun is known to bear at a certain
angle from the plane when the Pole
is reached, and during the circling
movement the angle may be plotted on
the chart. That makes one relatively
fixed point by which to fly
There is another fixed point, the south
magnetic pole, which, paradoxically, is
to the north. At the earth's Pole the
magnetic pole has a definite direction
and angle from the line of flight. This
angle can also be plotted.
So, after the plane makes its circle
and returns to one end Of the line of
flight, bisecting the course from Little
America, the navigator can get as near
as possible to his former southwark
course and turn away from Little
America for a time and, by means Of
the sun and the angle from the mag
netic pole. set his sun compass.
Then this compass can be reversed
100 degrees, the plane turned about,
and, on a course relative to the sun and
the magnetic pole. the flight home can
be begun with some certainty of arriv-
ing there.
Necessity of Calm. Sunny Day.
It can be seen that most of this navi-
CATION depends upon the weather. Aside
from the desirability of having as
calm q day as possible to minimize
drift, the sun Is absolutely necessary.
without the sun. observations could
not be taken, and the sun compass
could not be used to supplement the
sluggish and temperamental magnetic
compasSNin these ATTITUDES. Moreover,
nothing could be seen and photographs
, could not be taken, making the night
Valueless even II the Pole were reached.
The flight is for much more than
merely reaching the Pole, and as high
an altitude as the load permits will be
attained at the Pole, SO that wide
view may be had of the polar plateau.
Mountains may loom up directly past
the Pole, and it may be possible to see
| that the Queen Maude range runs in
definitely toward the Middle Sea.
| Importance Of Weather Factor.
| If the weather should become thick
| Just before the Pole was reached 1t
would be a great misfortune for these
reasons, although Comdr. Byrd believes
| that even then he could come near the
Pole and find his way back to Clear
weather by means of the magnetic COM
pass.
Nothing else would be of any use
under such conditions, and every one
who has been in high ATTITUDES knows
what an cratic instrument the mag
netic compass becomes in these regions.
So weather plays an important part
la the flight and 1t Is for this reason
that Comdr. Byrd laid down base at
the foot of the mountains on the Bar
rier so that II the weather seems bad
over the plateau when he arrives there
he can land on the Barrier and wait
has been planned so that 1t can be
changed to meet varying conditions.
Watches Set at Three Kinds Of Time.
The principal instruments being used
are a bubble Sextant, which gives an
artificial horizon; sun compass, mag
netic compass, drift indicator, charts
d and watches.
One watch was set at Greenwich true
time, giving the true time of the sun
which changes every day according t.
the time Of year. At present 1t varies
Is minutes from Greenwich civil time,
to "hich another watch was set.
/ he time of Little America Is IL
hours later than Greenwich civil time,
inasmuch as~we are going on 180th me-
ridian time. A third watch was set al
true local time. or sun time. which gives
the angle Of the sun from the line OF
flight.
(Copyrisht, 1929, by the New York Times
Co. and the st. Louis Post-Di patch All
rights for publicati reserved 5hroughout
the world. Wireless to the New York
Times.)