Admiral LEAHY. The present policy of the Navy Department, which has not been formally approved, but is the policy under which we are working is to not at the present time advocate the construction of more lighter-than-air rigid ships. The attitude of the Department seems to be now that it would be more advantageous for the Navy to use its funds for obtaining naval material that has proved of value to the Navy and that is needed and to leave the immediate future development of lighter-than-air craft to be undertaken by the commercial agencies of the Nation.

Mr. MAAS. I notice that Russia has begun to develop lighter-thanair. It has been assumed heretofore that Germany was the only nation carrying on its development, but in view of the fact that other nations are continuing or commencing development of lighter-thanair in their military force, it would seem to me that we ought no longer to delay in arriving at a policy ourselves in the development of lighter-than-air. It has great possibilities as aircraft carriers for one thing. I think that has been demonstrated. We have the world's supply of helium and are therefore in the most advantageous position of any nation on earth to develop lighter-than-air. Is it to be our naval policy to let this development escape us and be unprepared in that field?

Admiral LEAHY. It is impossible for me to make any statement as to what is to be the naval policy. The naval policy is not fixed and it changes from time to time. It is my personal opinion that the United States could very profitably engage in the development of. lighter-than-air. However, in view of the fact that no other Navy has undertaken the development of lighter-than-air craft and in view of the fact that there are many other elements of naval defense which are urgently needed, it is my opinion that we should work on those parts of the naval defense which are proved and are in the possession of foreign nations before we undertake a new development which is not yet considered important to any navy.

Mr. MAAS. If the lighter-than-air is to be developed as an agency of national defense, should it be developed by the Navy or the Army? Admiral LEAHY. I do not know.

Mr. MAAS. That is all.

Mr. BREWSTER. Referring now to the matter of landing an expeditionary force in the United States and the matter of aircraft defense, the situation as to vulnerability would be very different so far as transports were concerned as compared to battleships, would it not?

Admiral LEAHY. The transports would me much more vulnerable to air attacks than battleships.

Mr. BREWSTER. I notice your answer to Mr. Maas on battleships was very guarded, and the exact language was that the battleship was less vulnerable than any other type.

Admiral LEAHY. I think that is correct.

Mr. BREWSTER. Would you develop a little further your answer to his question as to the vulnerability of the battleship, as to the likelihood of success if such an attack occurred, without divulging any departmental secrets?

Admiral LEAHY. I can say that it would be exceedingly difficult to sink a battleship with an air attack and that the attacking aircraft would almost certainly suffer very severe punishment in making such an attack.

Mr. BREWSTER. Some have intimated that they could take a battleship into camp. Is there any actual, tangible evidence that could be properly evolved as to that?

Admiral LEAHY. We have not definite information as to how extensive an attack would have to be made in order to disable a battleship, although we have made extensive experiments to ascertain the amount of damage that is accomplished by bombs.

Mr. BREWSTER. You referred to the lessons of the Chinese experiences now going on. How far is it necessary for Japan to transport troops from Japan overseas to China?

Admiral LEAHY. It is approximately 450 miles from Nagasaki, Japan, to Shanghai, China.

Mr. BREWSTER. So that it is susceptible of overnight transit. Admiral LEAHY. That is about a 1-day journey, 24 hours at 20 knots speed.

Mr. BREWSTER. How far is it practicable for them to make an effective air attack off the coast now?

Admiral LEAHY. The longest experimental attack that I have any information of was about 300 miles. However, I am sure that land planes can be sent to much greater distances.

Mr. BREWSTER. In any expeditionary force to the United States, it would be necessary for a much longer maritime transit to take place, would it not?

Admiral LEAHY. That is correct.

Mr. BREWSTER. The facilities which you have for scouting would almost certainly disclose the approach of such a force, would it not? Admiral LEAHY. I hope so.

Mr. BREWSTER. They would then necessarily be exposed to air attacks during the daylight.

Admiral LEAHY. An expedition attempting to land troops on shore is first vulnerable to air attacks while approaching the shore, and then is vulnerable during the time it is required to transport the troops from the ships to the shore which is, perhaps, a much more dangerous position than during transit.

Mr. BREWSTER. I want to have it clear that it could be exposed to air attacks for a much longer period coming across the Pacific than it would if they were simply crossing to China from Japan. Is that correct?

Admiral LEAHY. That would be correct provided it had been discovered by the scouting lines.

Mr. BREWSTER. What was the lesson that was evident from the expeditionary force at Gallipoli, when the seas were completely controlled by a fleet?

Admiral LEAHY. It was very definitely demonstrated that it is extremely difficult to land troops against determined resistance. Mr. BREWSTER. Practically impossible.

Admiral LEAHY. No; it was not proved to be impossible.

Mr. BREWSTER. They never made any extension of their line in spite of all the force they could bring to bear.

Admiral LEAHY. They made very little progress with the force that they did bring to bear.

Mr. BREWSTER. At a tremendous sacrifice.

Admiral LEAHY. I believe the losses were heavy at Gallipoli.

Mr. BREWSTER. We have heard or read testimony by naval experts as to the matter of modern battleship fleets being blind and deaf. Will you comment on that?

Admiral LEAHY. No; because I do not understand your question. Mr. BREWSTER. I think that is addressed to the idea that in an engagement in the North Sea the British fleet was unable to keep up their communications between ships by radio or otherwise. Have you ever heard anything of that?

Admiral LEAHY. I have heard that they had some difficulty with their communications but as to the reasons for it I am not informed. Mr. BREWSTER. Has the radio been developed to a point where it can be relied upon for communication in such a situation?

Admiral LEAHY. I am not familiar with the situation that existed on the ships at Jutland. The radio is very reliable under ordinary conditions today.

Mr. BREWSTER. I am speaking now of battle conditions

Admiral LEAHY. If the radio room should be destroyed by gun fire, it would not be very useful thereafter.

Mr. BREWSTER. I have sufficient respect for your intelligence to think that you are aware that I address myself to the question of whether or not it is feasible to blank out the radio?

Admiral LEAHY. Are you speaking with respect to interference by other radios?

Mr. BREWSTER. Yes.

Admiral LEAHY. It is not.

Mr. BREWSTER. You are satisfied that radio has now been developed to the point that no engaging fleet could blank out your radio communications?

Admiral LEAHY. Not with interference at the present time.

Mr. BREWSTER. That was not true in the battle of Jutland?
Admiral LEAHY. I do not know.

Mr. BREWSTER. That is all.

Mr. KNIFFIN. In response to a question by Mr. Maas, you referred to the sea frontiers of America. I wish you would define the sea frontiers of America.

Admiral LEAHY. My understanding of sea frontier is that place. beyond which we do not expect to permit an enemy to approach our

coasts.

Mr. KNIFFIN. Would you include in your definition of sea frontiers the Philippine Islands?

Admiral LEAHY. No, I had no thought of including the Philippine Islands in that term.

Mr. KNIFFIN. The sea frontiers, as I recall from your previous testimony, would follow a line, roughly, drawn from the Bering Strait and from the end of the Aleutian Islands, to the Midway Islands, Samoa, Panama, and back, northerly to the eastern coast of Maine.

Admiral LEAHY. I did not refer to that in my previous statement as a sea frontier. I intended to convey the thought that that is the line which we hope to be able to cover in order to prevent an enemy getting to the eastward of it without being detected. It might be necessary to undertake to defeat the enemy outside of that line or inside of it.

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Mr. KNIFFIN. Beyond the boundary of such a line it might be necessary to undertake defense activities, beyond the boundaries of such a line?

Admiral LEAHY. It might be necessary to have a sea battle outside of that triangle.

Mr. KNIFFIN. You do not mean a great distance beyond that boundary?

Admiral LEAHY. No; I do not think it should be necessary to go a great distance beyond to defeat an enemy fleet.

Mr. KNIFFIN. If great distances beyond such boundaries were contemplated, then it might come within the policy that the best defense is an offensive, would it not?

Admiral LEAHY. It is entirely possible that the best defense would be an offensive, depending entirely on the conditions that existed at the time. I am unable to give you any statement as to where a sea battle might take place, because that is entirely dependent upon the conditions at the time. If it took place too far from our home shores and base of supplies, we might be at a great disadvantage on account of distance. I am sure whoever is charged with the defense of America in the next war will do his best to avoid going too far from his bases.

Mr. COLE. What means does the battleship have to defend itself against submarines?

Admiral LEAHY. In a battleship the principal defense against submarines is the construction of the ship.

Mr. COLE. Then it does not do it by mechanisms or some other means to destroy the attack of the submarine?

Admiral LEAHY. A battleship within itself has no means of destroying submarines. Of course it has ample gunfire to destroy a submarine when it appears on the surface. The destruction of a submarine in the Navy is accomplished by depth bombs.

Mr. COLE. Depth bombs?

Admiral LEAHY. Depth bombs and other methods of destruction are used by the Navy.

Mr. COLE. Is there any accepted ratio of the relative strength of a battleship of 35,000 tons as compared with submarines?

Admiral LEAHY. I have never head of such a comparison. Mr. COLE. If a battleship were found by itself would it be possible, then, for a few submarines to succeed in sinking it?

Admiral LEAHY. If a battleship should accidentally involve itself in a group of submarines, it would be extremely bad fortune for the battleship. But on account of the limited speed of submarines submerged, which is very limited, it is extremely simple for a battleship to escape if it knows that submarines are in the vicinity.

Mr. DELANEY. It is not likely that a battleship would be alone in a fleet of submarines.

Admiral LEAHY. It is not likely. It is a possibility.

Mr. COLE. The only thing that the battleship does have to defend itself against submarines is its superior speed?

Admiral LEAHY. That is all the battleship has within itself as defense against submarines.

Mr. BREWSTER. You do not believe in the isolation of a battleship? Admiral LEAHY. I do not understand the question.

Mr. COLE. Off by itself.

Admiral LEAHY. In time of war a battleship should not be alone on the sea unless its mission should be so important as to permit it to take chances.

Mr. COLE. In reply to a question by Mr. Maas, you say that the naval policy was not fixed but changed from time to time. You made that statement of the policy in regard to aircraft. Do you mean that to apply to your policy regarding airships or all naval policies?

Admiral LEAHY. The entire naval policy must be modified from time to time to bring it into exact accord with the national policy. The naval policy cannot be permanently fixed in its entirety. It can, perhaps, be permanently fixed in some of its elements, but the naval policy must agree with national policy, and as national policy changes, the naval policy, of course, must be changed to agree with it. That is the sense I was trying to make in my previous statement.

Mr. COLE. Then if your declaration of our present naval policy in the developments mentioned interferes, it can be changed to agree with our national policy.

Admiral LEAHY. The naval policy must be changed if it becomes necessary to bring it into agreement with the national policy.

Mr. BREWSTER. How do you coordinate the War Department and the Navy in defending the coasts in the event of war?

Admiral LEAHY. We carry out each year extensive experimental problems in which both the Army and the Navy participate.

Mr. BREWSTER. What has been the experience of other naval powers about the integration of their air force? What is their practice? Admiral LEAHY. What do you mean by integration?

Mr. BREWSTER. Putting it under one control.

Admiral LEAHY. The British air service was a separate service called the Royal Air Force. Within the last year the naval part of the British air arm has been placed directly under the Navy almost to the same extent it is in the United States Navy. In Italy it is a separate air service, I believe.

Mr. BREWSTER. For each arm.

Admiral LEAHY. A separate air service, and that part of it which is used with the Navy is loaned to the Army. In France-I am speaking only from memory-I believe the naval air arm belongs to the Navy.

Mr. BREWSTER. How about Japan?

Admiral LEAHY. In Japan the naval air service is very much the same as ours, separate and belonging to the Navy, although I am not familiar with the exact organization of the Japanese naval air force. We get very little information from Japan, while other nations are more frank in telling us how they handle their problems.

Mr. BREWSTER. To what extent do you coordinate with the Army Air Corps in interchange of plans and development of plans and purchase of planes-activities of that kind?

Admiral LEAHY. I feel sure that we have complete cooperation with the Army Air Corps, but the Chief of Aeronautics can give you detail information in regard to that.

Mr. COLE. Is a battleship more maneuverable than a submarine? Admiral LEAHY. Submarines are smaller and can turn more rapidly, but the battleship is very much faster. The problem for the submarine, which is a difficult one, is to get in a position which will enable it to make a successful attack on the battleship.