WITH the installation of the new radio direction finder on more and more Navy ships, an ever increasing number of navigators are slowly but surely welcoming and hailing a new shipmate and friend. For the information of those not blessed with this aid and to encourage its extensive use by those who are, this eulogistic account of the successful use of the Patoka’s instrument is gladly set forth.
Two days before her scheduled departure from the navy yard the Patoka went out for a postrepair trial and to test and calibrate a radio direction finder. It was formally introduced to the new navigator on the second day following, about two hours after his arrival on board, and received from him many glances of respect, doubt, and growing hope as the weather turned from snow through rain into fog, while a leaden sky indicated an early and intimate acquaintance. On that maiden voyage, the new instrument made firm friends for no sights were possible and Chesapeake lightship eventually oozed through the mist right where the bearings said it would.
From that trip on, this new aid to navigation has seen continuously growing and ever useful service. Confidence has grown with each group of bearings taken and found by simultaneous or later terrestial or celestial fixes to have been remarkably accurate.
This is not intended as a technical paper and no attempt to describe the make-up or "internal workings” of the instrument will be made here. Suffice it to say that it is a highly refined radiocompass with the deviation error corrected by a cam compensator which enables the navigator to read from the attached gyrocompass repeater the true bearing of any radio transmitter within the frequency range of the receiver. The application of a small correction converts this so that it may be laid down on a chart just as though the bearing had been taken with a pelorus.
To those who have been through the radiocompass problem of tracking a target by this means, the idea of tuning in on Diamond Shoals, Chesapeake, Winter Quarter, and Five Fathom Bank lightships for a fix when some one hundred miles from the nearest must have its appeal. Lines are set down and run forward to cross meridian altitudes, sun lines, or other direction finder lines, soundings are taken and plotted on these lines and all sorts of queer combinations are in every day use in the Patoka’s charthouse. And the possibilities of this new instrument are almost limitless.
The absence of radio beacons at some strategic points, the now decreasing silent stretches between operating periods and the low power of some led to the simple experiment of utilizing radio broadcasting stations for beacons. Experience has shown that such a station, located near enough to the coastline to eliminate errors due to the waves traversing land, makes an ideal beacon. Indeed it is quite common for the Patoka’s position approaching the Florida straits from the Gulf of Mexico to be indicated by the intersection of lines from Clearwater, Florida, and Havana, Cuba,— the work of the radio direction finder.
Of course it has its limitations. Until some kind friend of humanity invents an effective static eliminator, no radio receiver will produce enjoyable sounds in an electrical storm, and it is in stormy weather, when sights are impossible, that the importance of this installation is perhaps the greatest. Yet how much easier it is, instead of making an estimate, which must at best be a guess, as to what time to turn northeast to hold the Gulf Stream, for the navigator to say “With Jacksonville bearing west by radio direction finder, course should be changed.” Surely the great advantages of the new friend greatly outweigh its limitations.
I am going to yield here to the temptation of sketching a Jules Vernian possibility for the future. Aircraft today make use of radio beacons in locating landing fields and keeping them “on their course” during periods of poor visibility. An instrument on the dash records the amount and direction in which they creep off. Why not then, on the SS. “Tomorrow” a day out of Liverpool for New York, a needle in front of the helmsman which shows him “steady on” the radio beacon at Nantucket Shoals lightship—2,500 miles away? And why not go a step further and hook up two of the present-day navigational wonders? Why not a “metal mike” operated by a radio direction finder? With high-powered radio beacons at important points, the desired beacon would be tuned in, course set to agree with the bearing obtained and the “metal mike” cut in to hold her “steady so.” The visualized picture of a stream of ships riding down these main highways of the ocean may recall to many the pert comments of a beloved instructor in the chartroom of the navigation department at Annapolis:
“Gentlemen,” he was wont to say, “I wish you would remember that there are no whitewashed tracks on the ocean and no signposts to tell you when to change course!” Perhaps the radio beacon and the radio direction finder may yet eliminate this sad deficiency.