Flying the Atlantic in Sixteen Hours / With a Discussion of Aircraft in Commerce and Transportation

by Sir Arthur Whitten Brown

Weather difficulties are likely to be much less severe than might be imagined. Rain, hail and snow should have little influence on the navigation of airships. An outer covering that is rainproof and non-absorbent avoids the absorption of water and the consequent increase of weight. Hail and snow cannot adhere to the surface of the craft when in flight, owing to its high speed through the air; and, in any case, the precipitation height being not more than eight thousand feet, they can be avoided by flying above this altitude.

Fog may give trouble in landing, but during the journey an airship can keep above it. If the terminal were enveloped by fog an arriving ship could pass on to an emergency landing ground away from the fog-belt; if the mistiness were slight, it could remain in the air until the ground were visible, making use of its margin of fuel beyond the amount necessary for the London-New York flight. Airships in fog may be enabled to find their landing ground by means of captive balloons or kites, and of strong searchlights from the ground. At night, the balloons or kites could carry electric lights, with connections from the aërodrome.

In any case, fog, rain, hail and snow are nearly always local in their occurrence, and can be avoided by a short deviation from the usual route. Atlantic records indicate that on the main steamship routes fog sufficient to impede navigation does not occur on more than about twelve days in the year.

Wind is a factor that needs more careful study in its relation to transatlantic air navigation. In most cases, unduly strong winds can be dodged by flying on a higher level, or by cruising on a different course, so as to avoid the storm belt. Heavy storms, which are usually of a cyclonic nature, rarely cover an area of more than two hundred miles diameter. Moreover, the rate of progression of a cyclonic area is much less than the speed of the air movement. An airship is able to shake off a cyclonic area by a deviation from its course of not more than two hundred miles. Once away from the storm belt, it has no difficulty in keeping clear of it.

When higher levels of the air have been charted, there is every reason to believe that the known movements of the Atlantic winds will be used to shorten air journeys. There are at sea level, between certain clearly defined latitudes, prevailing winds of constant direction. At greater heights, also, there is in most latitudes a constant drift which, if charted, might be useful even if winds at sea level were unfavorable.

Although precise information is available of the prevailing and periodic winds at sea level in various latitudes, very little coördinated work appears to have been done in charting the prevailing and seasonal winds in higher levels of the atmosphere. Observations of the air currents over various localities in the United States, England and Germany have been taken, but very little is known of the winds above the great ocean tracts. There is a great necessity for international research to provide data for predictions of weather conditions in the upper atmosphere and thus enable advantage to be taken of these higher currents.

At high altitudes, constant winds of from thirty to forty miles per hour are common. If the prevailing directions of those were known to airship navigators, the duration of the journey could be considerably shortened, even if this meant taking an indirect route. It is undesirable to fly at great heights owing to the low temperature; but with suitable provision for heating there is no reason why flying at ten thousand feet should not be common.

Air currents cannot be charted as exactly as sea currents; but much valuable work can and will be done by tabulating in detail, for the guidance of air navigators, the tendencies of the Atlantic atmospheric drifts. Reliable charts, used in conjunction with directional messages from wireless stations and ships, may make it possible for vessels on the London-New York air service always to avoid troublesome winds, as well as storms and fogs, and to reduce the percentage of risk to a figure not exceeding that relative to sea liners.

For the rest, the excellence of the most modern engines and the fact that one or two, or even three of them can be temporarily out of action without affecting the airship's stability during a flight, minimize the danger of a breakdown from loss of power. The only remaining obstacle to reasonable safety would seem to be in landing on and departing from the terminal during rough weather. This can be overcome by the recently patented Vickers Mooring Gear for Rigid Airships.

The gear, designed so as to permit an airship to land and remain moored in the open for extended periods in any weather without the use of sheds, consists principally of a tall steel mast or tower, about one hundred and fifty feet in height, with a revolving head to which the craft is rigidly attached by the nose, permitting it to ride clear of the ground and to turn round in accordance with the direction of the wind. It is provided with a hauling-in winch and rope to bring the ship up to the mooring point.