SPECIAL ARTICLE.

Waimate Daily Advertiser, Volume XXIV, 7 May 1928, Page 5

SPECIAL ARTICLE.

IS THE NAVY DOOMED? (Bv Brigadier-General P. R. C. Groves, C. 8., C.M.G., D. 5.0.) On the supposition that war, which history shows is a recurring phenomenon may recur, this country has spent a total of £116,000,000 on national defence during the financial year which is now ending. The Service estimates for the new: financial year are about to be discussed, and the urgent need for economy demands that these shall be reduced to the minimum necessary to provide adequate national security. The object of this article is to show that both security and economy call for a redistribution of our defence expenditure in favor of air power. The last report of the Committee of Imperial Defence, published in 1924, stated that. “While the menace from the air has greatly increased . . . the liability of the country to sea-borne invasion has completely diminished compared with pre-war standards.” The potential menace referred to is twofold. First, it involves the risk, in the event of war, of a knock-out blow from the skies. So great has been the development of air power on the Continent that, according to Sir Samuel Hoare, the air force of otie State could now drop, ' within the first 24 hours of hostilities, a weight in bombs equivalent to the total weight (300 tons) dropped by German aircraft in this country in the course of the whole war, and continue the process indefinitely. Secondly, there is the risk of our seaborne food supplies being sunk by aircraft attack both in home waters and in port. An exhaustive series of tests carried out in American waters has proved that aircraft can easily sink surface craft. The targets were ex-German warships, such as the Ostfriesland, obsolete American cruisers, such as the Virginia, New Jersey, and Alabama, and a number of smaller vessels. A few bombs sufficed to sink these ships and strange to say, it was found that a “near miss” was even more effective

than a direct hit. The reason is that water is non-com-pressible; consequently the effect of a big under-water detonation close to a ship is to deliver a tremendous blow on the submerged portion of her hull, which is extremely vulnerable. A board of experts who reported on the results of the test stated that:— “It will be difficult, if not impossible, to build any type of naval craft of sufficient strength to withstand the destructive forces that can be obtained with the largest bombs that airplanes may be able to carry from shore bases or sheltered harbors.” The largest bomb employed in these tests, which were carried out several years ago, weighed 2,0001 b. Since then bombs weighing 4,0001 b have been dropped by aircraft. But far more important than this increase in the size of the missiles is the development of a new accessory in air warfare which will greatly facilitate their use. This is the smoke screen. Aircraft can now swiftly create such screens, both horizontally and vertically, on an immense scale. Under cover of these they can approach surface craft and attack with bombs and torpedoes from point-blank range. Some naval experts contend that-

deck armor and under-water “blisters’’ will enable warships to withstand such attacks; but many eminent naval architects disagree and endorse the abovequoted opinion of the American board of experts. Be that as it may, certain it is that merchant ships would fall an easy prey to aircraft. They possess no protection either above or below the waterline; aircraft could, therefore, dispose of them very quickly in home waters, and a few “depth charge” bombs in crowded harbors would inevitably result in wholesale sinkings. Anti-aircraft guns could not protect them, for the percentage of hits which can be obtained on aircraft is so small as to be almost negligible. It is an established principle that the only effective means of defence against aircraft is aircraft. Hence, in order to guard against the dual menace of a knock-out blow from the skies and the destruction of our sea-borne food supplies, when they near the land, » ’ must possess adequate air defence. Admittedly this, the primary essenti 1. does not at present exist. Its provision has been subordinated to other requirements, which, however needful, are nevertheless obviously of secondary importance. To sum up—air power, wifhin izradius of action, which is constant > increasing, has supplanted sea powei as the key weapon in national defence; Economy as well as security, for an force is the cheapest form of force, demands that this truth shall be recog- , nised and given full weight in our defensive preparations.