Evening star. [volume] (Washington, D.C.) 1854-1972, 1931-05-17

ference to consider amendments to the
international airfnail regulations which
are regarded as necessary in the light
Of experience since adoption of the reg
lllatiorls now in force two years ago will
be urged ny the chamber.
The time is not yet ripe for an inter-
national regulation OF special t1terna-
tional ali. exhibitions and fairs, in the
opinion OF officials of the chamber, who
believe that such regulation should be
postponed Until 1t Is found to be neces-
Sary by the manufacturers concerned
and sought by them.
1t has been found that existing Gus
toms regulations, especially those gov
erning atrports, present drawbacks for
commercial air traffic, and the chamber
asks that customs administrations con-
slider the possibility of creating at Gus
toms airports bonded warehouses as a
means Of facilitating customs operations.
Air Block Lights" Tried.
A weeks trial of an airline "block
lighting" signal system somewhat SINH
lar to those used on railroads has con-
WINGED officials OF the Ludington Line.
operating hourly service between the
National Capital and New York, that q
valuable new safety device has been
found.
Block lights now are installed at five
points between the two terminals and
later will be located every 20 miles along
the line TO control the movement of the
planes, which now are making q total Of
80 regular flights daily, Is each way.
The lights are red, incloeed In q
tubular gun" trained along the axis Of
the airway at an angle Of three degrees
above the horizon. The lights can be
seen easily in the brightest sunlight at
distance Of three miles from attitudes
Of 1000 feet or more. Two gums"
pointing along the airway in each direc-
ton. are located at each Of the five in
termediate stops on the line-Baltimore
Wilmington, Philadelphia and Trenton.
Henry j. Brown, veteran mail pilot
and assistant operations MANAGER of the
line, controls all the lights from q mas
ter switch at Washington Hoover Air
port. A red light at any Of the block
signal stations Is an order for the pilot
TO land. II there is no light he goes on.
Landings can be made on order for
passengers or the planes can be ground
ed ct any one Of the I'VE intermediate
stops to prevent their running into
storms ahead. Signals previously have
been made by flags, which have proved
unsatisfactory. In many cases north
and south bound planes have seen the
flags and landed, though the signal was
intended for only one of them. This
cannot happen with the lights, 1t was
explained
The lights were planned by Luke
Harris, maintenance chief Of 1.-THE line.
as q result Of the success of Somewhat
similar air trafhc lights at the local
terminal field.
Though the lights now are located az
only five intermediate points. it is plan
ned to locate them at intervals Of 20
miles along the line.
Electric Eye" Pierces Fog.
Airport or airway beacons can he To-
Gated through fogs too dense for the
human eye to pierce by an electric
eye" or photoelectric tube which has
been developed for airplane use. The
apparatus works either by day or night
The tube measures comparative light
intensitieS from opposite sides of the
plane in which 1t is mounted, though
the difference or even the presence Of
light may be imperceptible to the
eye, owing to the dispersion Of the light
rays by the fog.
Not only will the tube reveal whether
the light Is to the right or left or d.
rectly on the line of fight, but win
show whether the plane is approaching
or leaving the light.
To prevent the EYE" from respond