Peculiar Properties o[ Wood

Make it Indispensable in Airplane Construction

Washington, Oct. 22.-To paraphrase the advertising slogan of 1 well known cigarette manufacturer, wood, to occupy the place it does in modern airplane construction, has 'igot to be good". Wood has held a commanding position in what w1 consider the present advanced stage of aviation, despite efforts to find better qualities in alternate materials. It is the one material upon which scientists are counting in the projected and, now considered thoroughly practical, navigation of the upper stories of the air-the stratosphere.

The French Air Ministry, it has become known, is actually building a plane that is expected to fly from Paris to New York in from five to seven hours. It will follow levels, high above the airplane "ceiling" we now know. Wherever possible, principally because of temperature requirements in such cold levels, wood and silk will be used fbr construction. What will happen to control wires and other parts where it has been found necessary to use metal, is the problem causing the engineers the greatest present concern.

The Farmans, building the new plane, have always been partial to wood construction. In their factory at Billancourt, wood is reckoned the one construction material for bodies that has stood the test of time and shown itself the superior material for such purpose through all periods ol llesign development. Because of the "strength per pound of weight" factor which it offers, its resiliency and toughness, and its ability to withstand low temperatures, it was chosen for the new ship.

It should be remembered that the French are not merely seeking to establish a speed record. They at'e attempting to establish French military supremacy in aviation through superior development rather than quantity production of plines. The new plane, though based.on the Farman "19O" model and strongly resembling a medium-sized monoplane, is said to excel in effective design any plane yet practically conceived. It is this superiority that gives importance to the place that wood has already achieved in its design and whiih practically assures its future preeminence in plane construction.

"The moment the news of this momentous flight flashes around the world" a recently published account of the project states, "all commercial and military planes in ex' istence will be as obsolete as a horse and buggy." And further speaking of the wood construction, this same ac. count says:

"The plane itself is of wooden and linen construction, partly because the Farman engineers are convinced that wooden framework has many advantages like resiliency over metal, and also because all metals except pure aluminum become extremely fragile and delicate at the low temperature encountered at 65,00O or 75,000 feet (12 to 15 miles). There is no trouble about the motor, as it will remain warm, but the air ministry experts are still uncertain how control wires and other metallic parts, unheated by the motor, will act. The strongest steel cracks like a thin china plate if cold is sufficiently intense."

There is no certainty just what conditions beyond low temperatures will be met in the stratosphere. Moderate currents are hoped for. Strong headwinds, it is pointed out, will delay flights while tailwinds may add one hundred miles per hour to speed. An average speed of 400 or 500 miles per hour through the stratosphere is looked forward to.