ALONG A BEAM

Evening Post, Volume CXV, Issue 12, 16 January 1933, Page 8

ALONG A BEAM

HOW PILOTS FLY

THEIR WIRELESS EYES

A SURE WAY FINDER

Blanketed between clouds aud fog, with no gleam of guidance from earth or sky, the up-to-date air pilot "rides on a radio beam" —to safety! With his telephone headpiece ticking into his ear the identifying signal pouring in a steady stream from the next landing station, he finds his way "blind" as surely as if his eyes were glancing over a well-known landscape in broad daylight. Something of it has been told before, but now we have more details, and interesting ones, too. It's one of .the latest, triumphs of practical aviation, and "it is being done every day, every night, and right over our heads," says Allan A. Barrie in "Western Plying." The Federal Airways System, according to'Mr. Barrie, "represents the nerves of American aviation, a network of approximately 19,000 miles of lighted and radio-equipped airways that makes flying by day or night almost as certain as following the glistening steel of a railway or the marked and fenced border of a highway." He adds: The entire set-up of radio beams, revolving beacons, ' airways weatherbroadcasting stations, course-markers, and intermediate landing fields is staggering in its entirety. Each of "the nation's sixty 'radiorange beacons shoots a guiding finger in four directions at the same time. Here Mr. Barrie invites us to take a ride on the beam: Suppose we' are flying at 8000 feet from Los Angeles toward the radiorange station at Fontana, at the south end of Cajon Pass. We put on tho headphones and hear from Fontana a dash-dot, an "N" in Morse code." It shows that wo are too far to tho right of the centre of the beam. A "STEADY SIGNAL. ' 'As we swing to the loft, the dash-dot slides into a steady dash, or a continuous monotone signal of about twelve seconds' duration. This signal is interrupted five times a minute by the station-identifying signal, dot-dash-dot. When the dash or buzz is .continuous,' we know we are headed right for tho beacon station and a Department of Commerce landing field. • The beam is approximately seven to ten miles wide, 100 miles from the station, and narrows down to a few feet as we approach the' field.

Isow, inclining to the left, we hear the steady signal break, this time'to a, dot-dash, letter "A" in Morse code. The signal gets- louder as we approach the beacon; then breaks off." The interruption tells us that we have flown into the cone of silence above the'station, and that the station is directly below.

In the event that we cannot see the ground but know that the ceiling and visibility are sufficient, we can glide down through the fog and land at the field. But instead of landing, let 'us continue through Cajon Pass by : turning to the left and picking up the beam that leads out toward the desert. As we go out on this beam with the station now behind us, the dash-dot will again be on tho right side aud the dotdash, A, on the left side, with the continuous buzz, as always, in the centre. This north beam suggests a southwest beam from. Daggett in the vicinity of the Baldy Mesa intermediate field, located at the top of the Cajon Pass. CHANGED COURSE. The course liere changes from northwest to north-east toward Daggett The change\ in direction is indicated" by what is known as a ' marker beacon, which gives ont a.signal of three sharp dots and can be heard for a distance of threeto sis miles from the station. A radio-marker beacon is operated on the same frequency as that of the radiorange course on which it is located. This simplifies beam flying by indicating the exact intersection of two beams* Here our radio can be tuned to the next station and the compass changed to the new^ beam, all without losing a moment's time and without wandering a mile off the course. - ' ■ -I

The mail has actually been flown through rain and clouds, blind, for more than two-hundred miles," Mr. Barrie tells us, pointing out that "radio-beam and instrument flying are the most recent additions to airline flying, and high hopes are held for the future." And he reminds us that "at night, we also use revolving airway beacons. Tiiey are especially helpful in bad weather when it is necessary to fly close to the ground with limited'visibility. _ Imagine yourself in {he cockpit flying in a suow '.storm at night. The ceiling is coming down and the visibility is getting short. The four or five beacons and blinkers which you have beeji watching ahead and behind have gradually blurred out, and 'only 'one ahead and one behind are visible. Even these are beginning to get yellow and fuzzy. MILES AWAY. The situation is probably this: The next field is five or six miles away, and you are going to make it if you can. You have probably just passed a beacon with a red course light and you know that ahead you must see a blinker, a revolving beacon with a red course light flashing "D," another blinker, and another revolving beacon flashing green, located 200 feet from the south-east corner of the landing field. These thoughts run through one's head much more quickly than it takes time to tell.

You get to the next beacon with the red course light, and still are 100 feet off the ground by the altimeter. Since blinkers are not as bright as the beacons, it is possible that the next blinker will not become visible for a few moments after you have passed the beacon You reach the blinker, pass it, and look back to be sure it does not fade out before the green beacon appears. .When you see the green flashing beacon, you fly directly toward it because you must fly around and look at the wind sock to determine the direction of the wind before landing. The beacon is fifty-one feet high. Circling the neld for a landing, we dare not go any lower for fear of striking telephone wires. We land over the green boundary lights and taxi to the house at the beacon tower.

The house contains,blocks for the wheels, ropes, and pins to stake the ship down, covers for motor and cockpit, gasoline and oil, and most important on a cold night, an electric stove.