Prologue to Pearl Harbor: The Spy Flight that Wasn’t, Part I

Today’s post is written by Dr. Greg Bradsher, Senior Archivist at the National Archives at College Park, MD.

On December 4, 1941, at 9:08 pm, at Hamilton Field, located along the western shore of San Pablo Bay in the southern portion of Novato, California, 1st Lt. Ted Faulkner with his crew in their Consolidated B-24A Liberator (40-2371) bomber, roared down the runway, took off and headed toward the lights of San Francisco and over the Golden Gate Bridge and into the night, heading west out over the Pacific Ocean. Their destination was Hickam Field on the island of Oahu some 2,400 miles away. Their mission was to fly to Hawaii, thence to Midway and Wake Islands, and then to Port Moresby, before heading to Darwin and the Philippines. On the flight from Wake to Port Moresby, Faulkner was to fly a reconnaissance mission over the Japanese Mandates to obtain photographic intelligence of Japanese military and naval bases, which had been significantly built up during 1941.[1]

The story of Faulkner’s flight begins in mid-November when United States Navy radio intelligence units in the Philippines (Station Cast) and Hawaii (Station Hypo) noticed increased Japanese naval radio traffic. They believed that radio traffic indicted that Japanese air, land, and sea forces were gathering for a movement south, but did not know where or when. To make it even more troublesome was the fact that of the ten Japanese carriers they could only account for two or three.

On November 12, American traffic analysis disclosed that on October 17 new call signs had appeared in Mandate traffic indicating a decided increase in Japanese forces there. And disclosed on October 18, was the fact that the islands of Truk, Palau, Jaluit, and Saipan were being included in dispatches which would not affect them under ordinary circumstances. Apparently several new units were even being added to the Sixth Base Force in the Jaluit area. By November 18, the movement of Japanese air groups and air forces formerly associated with the China Sea area were predominately towards the Mandates. The Commander of Air Squadron 24 and the Commander of the Yokohama Air Group were in the vicinity of Wotje and maintained close contact with the Commander of the Combined Air Force. Units that included the flagship of the Commander-in-Chief of the Third Fleet (formerly the First Air Fleet) were enroute to the Mandates. In fact, the frequent changes in location of the Air group commanders between Saipan, Truk, Jaluit and Wotje produced considerable confusion on all mandate circuits. After careful observation of these units, American traffic analysts were of the opinion that the First, Second, Third, and Fifth Fleets were ready to move into the Mandates with submarine forces and combined air forces of the Combined Fleet. [2]  

Navy codebreakers reported on November 20 and 21 that there was unusually heavy radio traffic between Tokyo to all major commands. On the latter date, Chief of Naval Operations, Admiral Harold R. Stark, informed commanders of the United States Pacific and Asiatic fleets that reliable reports indicated that Japanese air and surface craft were patrolling shipping routes from the United States to Australasia, with special emphasis being placed on the Gilbert (with daily flights from Jaluit) and Ellice Islands area (with surface vessels).[3]

By November 22, the Japanese mobile striking force (Kido Butai), organized for the attack on Pearl Harbor, had rendezvoused in Tankan Bay (Hitokappu Wan) on Etorofu, biggest of the Kurile Islands. That day Vice Admiral Chūichi Nagumo, Commander in Chief Fleet Air Force and commander of the striking force, received orders to sail on November 26 and instructions that “In case negotiations with the United States reach a successful conclusion, the task force will immediately put about and return to the homeland.” On November 26, Nagumo’s force departed under complete radio silence from Hitokappu Bay for its destination 200 miles north of Oahu. His force consisted of 6 aircraft carriers (2 each from Carrier Divisions 1, 2, and 5), two heavy cruisers, one light cruiser, and nine destroyers, an advance patrol of 3 submarines, and a train of eight tankers.[4]    

The codebreakers reported on November 23 high precedence traffic increasing. Indications were that Third Fleet units were under way in a movement southward coordinated with Second Fleet, and a Southern Expeditionary Force, and other units. That day, Lt. Joseph J. Rochefort, in charge of the Combat Intelligence Unit in Hawaii, reported that “Cardiv 3 [carrier division] definitely associated with 2nd Fleet operations.”[5]

“All our traffic analysis,” later wrote then Lt. Cmdr. Edwin T. Layton, Fleet Intelligence Officer, United States Pacific Fleet, “continued to show that preparations were being made for a southward advance through the South China Sea, with Malaya, the Dutch East Indies, and probably the Philippines being the probable objectives.” The Third Fleet was also such a frequent addressee that Layton and Rochefort believed it must be the main amphibious invasion force, because it appeared prominently in communications with the commander of shore-based air units in Indochina. Station Cast from Cavite estimated a carrier division could be in the Palaus, but they remained convinced that at least one of its carriers would operate as far east as the Marshalls. Layton so informed Admiral Husband E. Kimmel, Commander-in-Chief, United States Pacific Fleet.  “We were wrong,” Layton later wrote, “in our deductions about the Japanese carriers.” [6]

The codebreakers reported on November 24 an increased activity among Third Fleet addressees with a high percentage of movement reports. On the same day unusual activity was noted in the Mandates on the part of the Japanese. Coast batteries, lookout stations and landing forces were identified on Truk and Saipan. From these and other indications it was assumed that similar Japanese defense preparations were being made at islands in the Jaluit and Palau vicinities, where bases were already located. [7]

On November 24, what appeared to be exchanges between Jaluit and the commander of carriers persuaded Rochefort that there was a definite indication that “one or more Cardivs are present in the Mandates.” According to Layton “This was far and away the most potent danger to Pearl Harbor. Again, it fit in with the overall picture of the force in the Marshalls as being the easterly component of the large task force that was building up to conduct the southward advance and attack the Philippines and Malaya. This conclusion came from an association of the call signs of many Second Fleet warships with the addressees of base commands in Formosa, Hainan, and French Indochina.” [8]

Although on November 24, Rochefort was cautioning “no definite indications of location of carriers,” Rochefort’s traffic analysts predicted that at least one, and possibly two, of the Japanese carrier divisions would be associated with the movement and that one might be heading from Japan for the Marshalls.” According to Layton, “Kimmel was following these reports very closely, the assumption being that wherever the carriers were located would highlight the main thrust of the Combined Fleet.” [9]

On November 24, Admiral Stark met with the Army Chief of Staff, General George C. Marshall, to discuss a message that he was planning to send Kimmel and Admiral Thomas C. Hart [Commander of the United States Asiatic Fleet]. That afternoon Stark sent a message to Kimmel, Hart, and various naval districts that chances of a favorable outcome of negotiations with Japan were very doubtful and that “this, coupled with statements of Japanese Government and movements their naval and military forces indicate in our opinion that a surprise aggressive movement in any direction including attack on Philippines or Guam is a possibility.” He added that Marshall had seen this dispatch and concurred and requested the addressees to inform Senior Army officers in their areas. He concluded by stating that “Utmost secrecy necessary in order not to complicate an already tense situation or precipitate Japanese action” and that Guam would be informed separately.[10]

Later, before the Navy Court of Inquiry, Kimmel said in regard to the November 24 dispatch he received: “There was, in my opinion, a possibility of an aggressive movement, and the dispatch itself indicated an attack on the Philippines or Guam was a possibility. I felt that this required no action by me further than that which I had already taken and I did not stop the training program. At this time I considered that an air attack on Pearl Harbor was a remote possibility. However, if Japan attacked the Philippines, a submarine attack on Pearl Harbor could be expected.” [11]

Where would the submarines come from? Kimmel undoubtedly believed they would come from the Mandates. Stark, knowing the increased presence of the Japanese naval forces in the Marshalls probably expressed his concerns to Marshall about the Japanese naval forces in the Mandates and perhaps suggested to him when they met on November 24, the need for an Army photographic mission over the Mandates.[12] Either late that day, or the first thing on November 25, Marshall most probably discussed a photographic mission with Maj. Gen. Henry H. Arnold, Chief of the Army Air Forces, and instructed Arnold to undertake the mission.[13]

Arnold knew the importance of the mission. He did not want the Japanese secretly sailing up from the Mandates and destroying the airfields at Wake and Midway islands. Plans had already been made to reinforce the Philippines in early December with B-17s flown from the mainland and without those airfields available it would not be able to do so in a timely manner.[14] When asked during the Pearl Harbor Board hearings whether he considered the developments in the Mandates a threat to Midway, Wake, and Hawaii, Arnold responded “In my opinion it was a direct threat against my airway across the Pacific, because it cut my airline in two.” In response to a similar question about the Japanese activities in the Mandates being a threat to Midway, Wake, and Hawaii, Arnold said “Against Midway and Wake, certainly; and possibly, against Hawaii. Looking back on it now, I cannot remember that we were all so much worried about the immediate attack on Hawaii. It was always a possibility; but we all thought there certainly would be an attack against Midway and Wake.” [15]

With respect to all the radio traffic that had been intercepted to this point Layton later testified:  “From receiving these from day to day there was no doubt in our minds that a task force was being formed.” But where would the task force be formed and when? On November 25, the codebreakers reported that high level of traffic suggested that organizational arrangements or other preparations were not yet complete. They also reported that one or more carrier divisions were then in the Marshalls. Compounding the work of the radio traffic analysts at this time was that beginning November 25, no identified Japanese aircraft carrier had originated a message or been addressed for action or for information. This most unusual situation occasioned several comments in the traffic intelligence summaries. [16]

Meanwhile, in Washington, D.C., the Chief of the Air Staff, Brig. Gen. Carl A. Spaatz, at the November 25 Air Staff morning meeting said that in connection with the next movement of B-17s to the Philippines a report had been received that there was quite a collection of Japanese surface vessels between Honolulu and Australia. Arnold, he said, wanted two B-24s to get over there and make a reconnaissance and take photographs, then proceed on to the Philippines for further reconnaissance from there. Spaatz directed the A-3 [Colonel Earl L. Naiden] to find out what planes were available and get them set to push off if such orders were issued.[17]

Image of B-24 plane on the ground.
An example of a B-24: the B-24 Liberator Bomber airplanes with gasoline barrels in foreground (NAID 85714447).

At noon on November 25, Marshall, Stark, Secretary of War Henry L. Stimson, Secretary of the Navy Frank Knox, and Secretary of State Cordell Hull met with President Franklin D. Roosevelt at the White House. At the meeting the President talked about the relations with the Japanese. He brought up the possibility that the United States was likely to be attacked perhaps as soon as next Monday “for the Japanese are notorious for making an attack without warning,” and discussed what action the United States should take. According to Stimson, Roosevelt said “The question was how we should maneuver them into the position of firing the first shot without allowing too much danger to ourselves. It was a difficult proposition.”[18] Later, during the Joint Congressional Investigation of Pearl Harbor, Senator Homer Ferguson asked Marshall if the planned reconnaissance flight was discussed at the White House meeting. Marshall responded “I do not recall, sir. It probably was mentioned.” To this Ferguson asked “Probably mentioned. Well, it was a very important mission, was it not, General?” Marshall responded “Yes, sir; it was important. Or, rather, I would say it was a rather delicate mission, because that was taking us directly over the Japanese islands and we had to consider whether or not they would grasp at that as a hostile threat.” [19]

When Stimson got back to the War Department on November 25 he found news from the Army G-2 that the Japanese expedition had started and were on ships sighted south of Formosa. He called Hull and told him about it and sent copies of the G-2 report to him and to Roosevelt. [20]

In a postscript to a letter Stark wrote Kimmel on November 25, Stark wrote:

P. S. I held this up pending a meeting with the President and Mr. Hull today. I have been in constant touch with Mr. Hull and it was only after a long talk with him that I sent the message to you a day or two ago showing the gravity of the situation. He confirmed it all in today’s meeting, as did the President. Neither would be surprised over a Japanese surprise attack. From many angles an attack on the Philippines would be the most embarrassing thing that could happen to us. There are some here who think it likely to occur. I do not give it the weight others do, but I included it because of the strong feeling among some people. You know I have generally held that it was not time for the Japanese to proceed against Russia. I still do. Also I still rather look for an advance into Thailand, Indo-China, Burma Road area as the most likely.

I won’t go into the pros or cons of what the United States may do. I will be damned if I know. I wish I did. The only thing I do know is that we may do most anything and that’s the only thing I know to be prepared for; or we may do nothing—I think it is more likely to be ‘anything.[21]

Brig. Gen. Sherman Miles, Acting Assistant Chief of Staff, G-2, on November 26 wrote Marshall, summarizing for him extracts from cables received in the Office of Naval Intelligence, together with G-2 comment thereon. He wrote that from Guam November 23 “Increased naval activity Truk, Saipan area. Indicated increase base forces in mandates.” Guam listed various naval forces in the Mandates and noted air force activity was increasing there. Miles reported that from information available in G-2 Division the Japanese strength in the mandated islands was believed to be 15,000 ground troops, 100 aircraft of all types, 4 light cruisers, 8 destroyers, and, 9 submarines. Miles wrote that the Navy Department had supplied the following comment on November 24 regarding Japanese activity in the Western Pacific: “Apparent establishment by Japan of combined air and surface patrol over shipping routes U.S. to Australia. Daily aircraft patrols observed extending over Gilbert Island from Jaluit. Surface craft believed covering areas extending to Ellice Island.” Miles reported the following information was received from the Commandant Fourteenth Naval District through the Office of Naval Intelligence at 12:45 am that day:

The Japanese have been organizing a naval task force for the past month comprising: Second Fleet. Under the command of Commander-in-Chief, Second Fleet; Third Fleet which formerly was the China Coast Command Force including its first and second base forces, constituted by miscellaneous small vessels; Combined Air Force consisting of all large carrier forces; Also destroyer squadron 8, air squadron 7, submarine squadron 5, and possibly 1 battleship division from First Fleet consisting of 3 battleships; The combined air force has assembled in Takao, Formosa, with some units believed in Hainan Island; The third Fleet is believed moving in direction of Takao and Bako, Pescadores off West Coast of Formosa, from home waters in Japan; Units from the Second Fleet are at present possibly en route to South China on advance scouts; Strong concentration of submarines and air groups in the Marshalls…Present location other units of this task force are not know[n].

The evaluation put upon the above information by Commandant, Fourteenth Naval District, was according to Miles, that a strong force may be preparing to operate in Southeastern Asia, while component parts thereof may be expected to operate from Palau and the Marshall Islands. [22]

Rochefort after the war observed that “About the 25th or 26th of November it also became apparent that there was a concentration of submarines and aircraft carriers, and it looked like one battleship division, in the Marshall area, which was one of the first indications we had had of close cooperation between the aircraft and the submarines.”[23]

Early on November 26, Stimson called the President and asked him whether he had received the paper which he had sent him the night before about the Japanese having started a new expedition towards Indo-China. “He fairly blew up” saying he had not seen it and that it changed the whole situation because “it was an evidence of bad faith on the part of the Japanese that while they were negotiating…they should be sending this expedition down there to Indo-China.” [24]

At 10:30 am on November 26, an emergency conference was held in Marshall’s office to hear him warn that Roosevelt and Hull believed that upon termination of talks with the Japanese envoys, Japan would “soon cut loose” with “an assault on the Philippines.” [25]

The weekly meeting of the Joint Army-Navy Board was held November 26 at 11:35 am. Present were Stark, Marshall, Arnold, Rear Admiral H. E. Ingersoll (Assistant Chief of Naval Operations), Maj. Gen. William Bryden (Deputy Chief of Staff), Rear Admiral R. K. Turner (Director, War Plans Division, Office Naval Operations), Brig. Gen. Leonard T. Gerow (Acting Assistant Chief of Staff for Plans Division), Captain D. C. Ramsely (Bureau of Aeronautics, in the absence of Rear Admiral J. H. Towers), and Colonel W. P. Scobey (Secretary). During a discussion of the Pacific situation, it was reported that the Navy had information that Japanese airplanes had been making reconnaissance and photographic flights over the United States islands in the Western Pacific. It was felt that in view of recent developments indicating reinforcements and activity in the construction of defense installations in the Marshall and Caroline Islands, efforts should be made on the part of the United States to photograph the most important of these islands. Arnold announced that two planes were already enroute from Dayton to the Philippines with photographic equipment and with instructions to photograph Truk, Jaluit, and such other important Japanese islands as required. With reference to this mission, Turner announced that Admiral Hart had proposed that the United States, the British, and the Dutch undertake to photograph all of the islands in the Far East and Western Pacific, but since the Army was engaged in the stated photographic mission, the Navy would like the planes to obtain certain specific information. Arnold proposed that the Army would assist the Navy in obtaining desired data if the Navy would furnish to him, without delay, a memorandum of exactly what was desired so that instructions could be given to the pilots engaged on the two photographic missions.[26]

After the Joint Board meeting Marshall left Washington, D.C., to review the Army maneuvers in North Carolina, and Stark radioed Kimmel, informing him of the impending photo reconnaissance mission.[27]

Also after the Joint Board meeting, on November 26, Colonel Earl L. Naiden and Colonel Victor H. Straham (Assistant Chief of Staff, G-3) discussed the photographic reconnaissance flight and agreed that the following instructions would be issued:

  1. That two (2) B4 aircraft would be made available immediately by the Ferry Command and that a combat crew and one photographer would accompany each aircraft. That guns and ammunition would be installed.
  2. That the two (2) B-24 aircraft would be delivered at the Sacramento Air Depot immediately.
  3. That the two (2) B-24 airplanes would proceed to the San Francisco area and be ready to depart on the mission within forty eight (48) hours.
  4. That take-off order from San Francisco area would be issued from this headquarters.
  5. That the aircraft would be included in the order governing flights from the San Francisco area to the Philippines.
  6. That additional necessary instructions regarding the flight would be received by the crews in Honolulu.
  7. That the crews would be prepared to remain in the Philippine Islands-permanent change of station.
  8. That the necessary photographic equipment and sufficient film to complete the mission enroute and to include any assigned missions in the Philippines will be carried from the United States.[28]

Then Naidan requested [November 26] a cable be sent to Lt. Gen. Walter C. Short, Commanding General, Hawaiian Department. [29] It was sent to Short, as message number 466 on November 27: “Within 48 hours there will depart from U.S. via usual route B-24 airplanes for the Philippines. Enroute from Wake to Moresby they will make secret photographs. Being sent you in separate message are instructions covering this photography and visual reconnaissance.”[30]

Arnold wrote Stimson on November 26, that it was contemplated that two B-24s would leave the West Coast within 48 hours for the Philippines. These airplanes, he wrote, had been provided the necessary camera equipment to take photographs while en route of reported fleet and air concentrations in the Marshall Islands. Other fleet and air concentrations, he added, had been reported in the Palau and Yap group and that photographs would be taken of these by the B-24s after arrival in the Philippines. The exposed position of Midway and Wake Islands, Arnold noted, made it mandatory that some means of protection be provided to insure their availability for servicing heavy bombardment airplanes scheduled for Philippines reinforcement. He then discussed the action being taken.[31]

After the Joint Board meeting, Admiral Turner wrote Arnold:

With regard to the photographic mission of the two B-24 airplanes flying to the Philippines this week, photographs and reconnaissance of Jaluit [pen and ink: or Ponape, if Jaluit is too far out of the way] and Truk are desired in order to ascertain number and location of ships, submarines, air fields, aircraft, guns, barracks or camps, and other important military features.

I would appreciate the issuance of instructions somewhat as follows:

  • Senior pilots of the aircraft should see Admiral Kimmel personally after arrival in Oahu and ask his advice, particularly if the operating limitations for the flight are such that a decision must be made to omit reconnaissance of one of the places.
  • The pilots should also ascertain, while at Honolulu, the best time of day for photography at Truk and Jaluit.
  • No dispatches should be sent from Moresby, in the interests of secrecy.
  • Upon arrival in the Philippines, a copy of the report and two copies of any photographs taken should be sent to Admiral Hart, Admiral Kimmel and the Chief of Naval Operations.
  • Inform Admiral Hart that the Chief of Naval Operations request him to dispatch a digest of the report to Admiral Kimmel, by radio.[32]

Image of memorandum from R.K. Turner to General Arnold.
Memo, R. K. Turner, Office of the Chief of Naval Operations to General Arnold, November 26, 1941, File: 373.2B Overseas Flights, Security Classified Central Decimal Files, January 1939-September 1942, Entry 293-B [NAID 6860411], Records of the Army Air Forces, RG 18
At 11:49 pm on November 26 the War Department sent the following message to General Short:

Reference two B dash twenty four airplanes for special photo mission stop It is desired that the pilots be instructed to photograph Truk Island in the Caroline group, Jaluit in the Marshall group stop Visual reconnaissance should be made simultaneously stop Information desired as to the number and location of naval vessels including submarines comma airfields comma aircraft comma guns comma barracks and camps stop. Pilots should be warned islands strongly fortified and manned stop Photography and reconnaissance must be accomplished at high altitude and there must be no circling or remaining in the vicinity stop Avoid orange aircraft by utilizing maximum altitude and speed stop Instruct crews if attacked by planes to use all means in their power for self-preservation stop The two pilots and copilots should be instructed to confer with Admiral Kimmel upon arrival at Honolulu to obtain his advice stop If distance from Wake and Jaluit to Moresby is too great comma suggest one B dash twenty four proceed from Wake to Jaluit and back to Wake comma then Philippines by usual route photographing Ponape while enroute Moresby stop Advise Pilots best time of day for photographing Truk and Jaluit stop Upon arrival in Philippines two copies each of any photographs taken will be sent to General MacArthur comma Admiral Hart comma Admiral Kimmel comma the Chief of Naval Operations comma and the War Department stop Insure that both B dash twenty four airplanes are fully equipped with gun ammunition upon departure from Honolulu. [33]

Several days later the War Department sent Short a message, indicating that with reference to its previous message, “Instruct crews if attacked by planes to use all means in their power for self- preservation.”[34]

At Naidan’s request on November 26, the following cablegram was sent that day, as #618, to General Douglas MacArthur, the Commanding General, U. S. Army Forces in the Far East:

Within 48 hours, for permanent station, there will depart from the United States for the Philippines 2 B-24 airplanes equipped for high altitude photography. Enroute they will perform photographic missions and report to you for similar missions as you may direct. A copy of their report and 2 copies of any photographs taken should be sent to War Department, Chief of Naval Operations, and Admirals Hart and Kimmel. Inform Admiral Hart that he is requested by Chief of Naval Operations to dispatch to Admiral Kimmel a digest of the report.[35]

Assigned the photographic reconnaissance mission were two crews of the 88th Reconnaissance Squadron, 7th Bombardment Group (Heavy), stationed at Fort Douglas, Utah. One plane would be piloted by 1st Lt. Ted S. Faulkner and the other by 1st Lt. Harvey J. Watkins. Watkins at the time was assigned to the 11th Bombardment Squadron, 7th Bombardment Group (Heavy), also at Fort Douglas. Both pilots were well-suited for the mission assigned them. They had seen service that summer with the newly formed Army Air Corps Ferrying Command, flying modified (for passengers) B-24As, from Bolling Field to Ayr, Scotland, via normally Montreal and Newfoundland.[36]

They received orders, apparently on November 26, to take their crews to the Sacramento Air Depot where they would pick up their planes and fly to Hamilton Field. At Sacramento the planes would undergo modifications to make them war-ready. The bombers had been stripped of combat equipment by Ferrying Command. Modifications were still incomplete when Faukner’s plane left Sacramento for Hamilton Field.[37]    

The commandant of the Fourteenth Naval District on November 26 advised the Office of Naval Operations and the commandant of the Sixteenth Naval District in summary form of information with respect to Japanese naval movements obtained by the Radio Intelligence Unit at Pearl Harbor during the preceding month. This dispatch expressed the belief that a strong concentration of Japanese submarines and air groups, including at least one carrier division unit (not necessarily a carrier) and probably one-third of the submarine fleet, were located in the vicinity of the Marshall Islands. The estimate of the situation was to the effect that a strong force might be preparing to operate in southeastern Asia, while some units might operate from Palau and the Marshalls.[38] It conveyed a distinct sense of alarm at events.[39] On the same day, the Radio Intelligence Unit in the Philippines advised Kimmel and Stark, among others, in commenting on the November 26 dispatch from Hawaii, that traffic analysis for the past few days indicated that the commander in chief of the Second Fleet was directing various fleet units in a loose-knit task force that apparently would be divided into two sections, the first of which was expected to operate in the South China area, the second, in the Mandates. It was estimated that the second section included a carrier from Carrier Division 3. This dispatch further pointed out that the commandant of the Sixteenth Naval District could not confirm the supposition that carriers and submarines in force were in the Mandated Islands and that his best indications were that all known carriers were still in the Sasebo-Kure area. The opinion was expressed that this evaluation was regarded as reliable.[40]

Layton would later testify that either Kimmel directed him to establish contact with the Hawaiian Air Force pertaining to this reconnaissance or else Colonel Edward W. Raley, Chief of the Intelligence Section, Hawaiian Air Force, came to him with the information of the pending reconnaissance and requested his assistance towards delineating the appropriate objectives and to furnish the pilots and crews with intelligence material for briefing. He was also requested to assist in the projected reconnaissance. Layton also later testified that he was particularly anxious that this reconnaissance be carried out to check on his information as to the presence or absence of air strength and carriers and submarines and naval concentrations in the Marshalls area, including Truk. This, he believed, was an ideal opportunity to establish the reliability of existing intelligence on Japanese naval dispositions and developments in the Mandated Islands.[41]

Layton, in testifying told Senator Scott W. Lucas that he believed that there were a carrier and two destroyers in the Marshalls themselves, and was delighted when the Army proposed a distance long-range, overwater reconnaissance of the Marshalls and the central Carolines to spot this task force down there. Lucas, responded: “Yes; well, how far did you think that these carriers were from Pearl Harbor at the time you made the estimate?” Layton said “I thought they were in the Marshalls themselves, and most likely at anchor in one of the atolls—Jaluit, possibly Wotje, and possibly Maleolap.” Lucas asked “How far in miles would that be, the nearest one, I mean, that the carrier might be based in?” Layton answered “From Jaluit to Pearl Harbor is 2,096 nautical miles.” He added “I believe that Wotje is a little closer. It is 1,970 miles. I believe that is about the nearest that has a good harbor and base facility.” [42]

It might be added that Kimmel also must have been delighted with the news that a photographic reconnaissance of the Japanese Mandates was going to be made. In one Pearl Harbor investigation he testified that “My recollection is that our orders were not to go anywhere near them.” He added that “We wanted to go into the Gilberts to make some surveys down there and find out something about the Gilberts, and the answer was that we should not evince any interest in the Gilberts, because the Japs might find out that we were interested.” “While I cannot put my finger on it,” Kimmel continued, “I am convinced that no reconnaissance of the Mandates would have been permitted by the Navy Department at that time. The only time while I was out there that a reconnaissance of the Mandates was authorized was a proposal to send a B-24 over and do some photographing.” [43] 

Part II of the Spy Flight that Wasn’t will appear Thursday, December 6, 2018.


Footnotes:

[1] Under the terms of Article 22 of the Covenant of the League of Nations, Japan was bound to prevent “the establishment of fortifications of military and naval bases” in the former German possessions in the Pacific mandated to her—the Marianas, Palaus, Carolines, and Marshalls. The neutralization of other Japanese-held islands was guaranteed by the Washington Naval Limitations Treaty of 1922, signed by the United States and Japan, as well as by the British Empire, France, and Italy. On March 27, 1933, Japan gave the required two years’ notice of her intention to withdraw from the League, and the official withdrawal was consummated on March 27, 1935. This action, being unilateral, did not relieve Japan of her obligation not to fortify the mandated islands under the terms of the Covenant. However, the League was powerless to enforce the Covenant and after 1935 the islands were for the most part closed to foreign visitors. Philip A. Crowl and Edmund G. Love, Seizure of the Gilberts and Marshalls, The War in the Pacific, United States Army in World War II (Washington, D.C.: Center of Military History, United States Army, 1993), pp. 206-209. Readers may find interesting my blog entitled Captain Alfred Parker on Jaluit Atoll, March – April 1937.

[2] The “Magic” Background of Pearl Harbor, Vol. 4 Appendix (Washington, D.C.: Department of Defense, 1977), p. 57 and Vol. 4 Appendix pp. A-45, A-74-A75.

[3] Frederick D. Parker, Pearl Harbor Revisited: United States Navy Communications Intelligence 1924-1941 (Fort Meade, Maryland: Center for Cryptologic History, National Security Agency, 1994), Appendix C: Highlights from COM-14 Daily COMINT Summary, p. 76; The “Magic” Background of Pearl Harbor, Vol. 4 Appendix (Washington, D.C.: Department of Defense, 1977), Vol. 4 Appendix p. A-87

[4] Investigation of the Pearl Harbor Attack, Report of the Joint Committee on the Investigation of the Pearl Harbor Attack, Congress of the United States Pursuant to S. Com. Res. 27, 79th Congress, A Concurrent Resolution to Investigate the Attack on Pearl Harbor on December 7, 1941, and Events and Circumstances Relating Thereto and Additional Views of Mr. Keefe together with Minority Views of Mr. Ferguson and Mr. Brewster July 20 (legislative day July 5), 1946-— Ordered to be printed with illustrations, 79th Congress, 2d Session, Document No. 244,  (Washington, D.C.: United States Government Printing Office, 1946), p. 57; Samuel Eliot Morison, The Rising Sun in the Pacific 1931-April 1942, History of United States Naval Operations in World War II Volume III (Boston: Little, Brown and Company, 1968), pp. 87, 89, 90; John Costello, The Pacific War (New York: Quill, 1982), p. 119; W. J. Holmes, Doubled-Edged Secrets: U. S. Naval Intelligence Operations in the Pacific during World War II (Annapolis, Maryland: Naval Institute Press, 1979),  p. 28.

[5] Parker, Pearl Harbor Revisited: United States Navy Communications Intelligence 1924-1941, Appendix C: Highlights from COM-14 Daily COMINT Summary, p. 76; Rear Admiral Edwin T. Layton, U.S.N. (ret), with Captain Roger Pineau, U.S.N.R. (Ret) and John Costello, “And I Was There”: Pearl Harbor and Midway-Breaking the Secrets (New York: William Morrow and Company, Inc., 1985), pp. 184-185.

[6] Layton with Pineau and Costello, “And I Was There”: Pearl Harbor and Midway-Breaking the Secrets, p. 185.

[7] Parker, Pearl Harbor Revisited: United States Navy Communications Intelligence 1924-1941, Appendix C: Highlights from COM-14 Daily COMINT Summary, p. 76; The “Magic” Background of Pearl Harbor, Vol. 4 Appendix (Washington, D.C.: Department of Defense, 1977), Vol. 4 Appendix p. A-90.

[8] Layton with Pineau and Costello, “And I Was There”: Pearl Harbor and Midway-Breaking the Secrets, p. 185.

[9] Layton with Pineau and Costello, “And I Was There”: Pearl Harbor and Midway-Breaking the Secrets, p. 186.

[10] Forrest C. Pogue, George C. Marshall: Ordeal and Hope 1939-1942 (New York: Penguin Books, 1993), pp. 203, 204; Message, Chief of Naval Operations, Ingersoll to CINCAP, CINCPAC, COM 11, COM12, COM 13, COM 15, November 24, 1941, File: Messages Between War Department and Hawaii From July 8 to December 7, 1941, Files Relating to Hearings and Investigations, 1944-1945 (Entry UD-37) [NAID 3890949], Army Pearl Harbor Board, Records of the War Department General and Special Staff, RG 165.

[11] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Pursuant to S. Con. Res. 27, 79th Congress, a Concurrent Resolution Authorizing an Investigation of the Attack On Pearl Harbor On December 7, 1941, And Events And Circumstances Relating Thereto (Washington, D.C.: United Sates Government Printing Office, 1946), Part 32, p. 231.

[12] This was something Marshall and Stark had been discussing in mid-October 1941. Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 16, 2215.

[13] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 3, p. 1288. Marshall had problems when subsequently testifying before a joint congressional committee pinpointing when he first heard about the need for the reconnaissance flight, and who had broached the possibility of the flight.  He testified that he believed that it was the Navy that had first brought the flight’s necessity to the Army and that it may have been at the Joint Board meeting on November 26 that the issue was first raised. Ibid., pp. 1290, 1291.

[14] Historical Division, Assistant Chief of Air Staff, Intelligence, Army Air Action in the Philippines and Netherland East Indies 1941-1942, U.S. Air Force Historical Study No. 111, March 1945, p. 38.

[15] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 28, pp. 91, 92.

[16] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 10, p. 4833; Parker, Pearl Harbor Revisited: United States Navy Communications Intelligence 1924-1941, Appendix C: Highlights from COM-14 Daily COMINT Summary, p. 76; Holmes, Doubled-Edged Secrets: U. S. Naval Intelligence Operations in the Pacific during World War II, p. 27.

[17] Staff Meeting, November 25, 1941, File: 337 Daily Diary of The Chief of Air Staff 23 June-6 Dec 1941, 4-14 July 1942, 18-30 Sept 1942, Security Classified Central Decimal Files (Bulky Files), 1939-1942, Entry 293-C [NAID 6860411], Records of the Army Air Forces, RG 18.

[18] November 25, 1941, Mr. Stimson’s Notes, Appendix to Statement of Henry L. Stimson, File: Simson, H. L., Secretary of War, Case Files of Individuals Connected with the Pearl Harbor Investigation (“Persons File”) 1945-1946 (Entry A!-167-D) [NAID 12092403] Pearl Harbor Liaison Office, General Records of the Department of the Navy 1798-1947, RG 80.

[19] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 3, p. 1288.

[20] November 25, 1941, Mr. Stimson’s Notes, Appendix to Statement of Henry L. Stimson, File: Simson, H. L., Secretary of War, Case Files of Individuals Connected with the Pearl Harbor Investigation (“Persons File”) 1945-1946 (Entry A!-167-D) [NAID 12092403] Pearl Harbor Liaison Office, General Records of the Department of the Navy 1798-1947, RG 80.

[21] Letter, Betty [Stark], Office of the Chief of Naval Operations to Admiral H.E. Kimmel, Commander-in-Chief, U.S. Pacific Fleet, November 25, 1941, File: Admiral H. R. Stark’s Letters to Admiral H. E. Kimmel, Files Relating to Hearings and Investigations, 1944-1945 (Entry UD-37) [NAID 3890949], Army Pearl Harbor Board, Records of the War Department General and Special Staff, RG 165.

[22] Memo, Sherman Miles, Brig. Gen., Acting Assistant Chief of Staff, G-2 to The Chief of Staff, Subject: Japanese Naval Task Force, November 26, 1941, File: Military Intelligence Estimates prepared by G-2, War Department, Files Relating to Hearings and Investigations, 1944-1945 (Entry UD-37) [NAID 3890949], Army Pearl Harbor Board, Records of the War Department General and Special Staff, RG 165.

[23] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 23, p. 679.

[24] November 26, 1941, Mr. Stimson’s Notes, Appendix to Statement of Henry L. Stimson, File: Simson, H. L., Secretary of War, Case Files of Individuals Connected with the Pearl Harbor Investigation (“Persons File”) 1945-1946 (Entry A!-167-D) [NAID 12092403] Pearl Harbor Liaison Office, General Records of the Department of the Navy 1798-1947, RG 80.

[25] Layton with Pineau and Costello, “And I Was There”: Pearl Harbor and Midway-Breaking the Secrets, p. 209.

[26] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 14, p. 1642.

[27] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 3, p. 1287; Layton with Pineau and Costello, “And I Was There”: Pearl Harbor and Midway-Breaking the Secrets, p. 210.

[28] Routing and Record Sheet. C.S., Chief of Air Staff to Commanding General, Air Force Combat Command, Subject: B-24 Mission, November 26, 1941, File: 452.1A Bombers, Security Classified Central Decimal Files, January 1939-September 1942, Entry 293-B [NAID 6860411], Records of the Army Air Forces, RG 18.

[29] Routing and Record Sheet, AAF A-3 to AAF AAG, Subject: Radiogram to Commanding General, Hawaiian Department, November 26, 1941, File: 311.22A Cablegrams, Security Classified Central Decimal Files, January 1939-September 1942, Entry 293-B [NAID 6860411], Records of the Army Air Forces, RG 18.

[30] Routing and Record Sheet, W.W.D., AAG to A-3, Subject: Radiogram to Commanding General, Hawaiian Department, November 27, 1941, File: 311.22A Cablegrams, Security Classified Central Decimal Files, January 1939-September 1942, Entry 293-B [NAID 6860411], Records of the Army Air Forces, RG 18. A copy can be found in Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 37, pp. 1205-1206.

[31] Memo, H. H. Arnold, Office of the Chief of the Army Air Forces to The Secretary of War, Subject: Situation in the Pacific, November 26, 1941, File 312.1-A, Classes of Correspondence, Security Classified Central Decimal Files, January 1939-September 1942, Entry 293-B [NAID 6860411], Records of the Army Air Forces, RG 18.

[32] Memo, R. K. Turner, Office of the Chief of Naval Operations to General Arnold, November 26, 1941, File: 373.2B Overseas Flights, Security Classified Central Decimal Files, January 1939-September 1942, Entry 293-B  [NAID 6860411], Records of the Army Air Forces, RG 18.

[33] Message #465, Adams to Commanding General, Hawaiian Department, November 26, 1941, 1149PM, File: Messages Between War Department and Hawaii From July 8 to December 7, 1941, Files Relating to Hearings and Investigations, 1944-1945 (Entry UD-37) [NAID 3890949], Army Pearl Harbor Board, Records of the War Department General and Special Staff, RG 165.

[34] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 37, p. 1206.

[35] Routing and Record Sheet, W.W.D., AAG to A-3, Subject: Cablegram No. A-3-158, November 27, 1941, File: 311.22A Cablegrams, Security Classified Central Decimal Files, January 1939-September 1942, Entry 293-B [NAID 6860411], Records of the Army Air Forces, RG 18.

[36] Robert F Dorr, B-24 Liberator Units of the Pacific War, Osprey Combat Aircraft 11 (Oxford, England: Osprey Publishing Ltd., 1999), pp. 6, 7; Robert F. Dorr, 7th Bombardment Group/Wing, 1918-1995 Second Printing (Revised) (Paducah, Kentucky: Turner Publishing Company, 1998) p. 48.

[37] Dorr, B-24 Liberator Units of the Pacific War, p. 90; Dorr, 7th Bombardment Group/Wing, 1918-1995,  p. 48.

[38] Report of the Joint Committee on the Investigation of the Pearl Harbor Attack, Congress of the United States, 79th Congress, 2d Session, Document No. 244), p. 133.

[39] Parker, Pearl Harbor Revisited: United States Navy Communications Intelligence 1924-1941, p.44.

[40] Report of the Joint Committee on the Investigation of the Pearl Harbor Attack, Congress of the United States, 79th Congress, 2d Session, Document No. 244, pp. 133-134.

[41] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 39, p. 491.

[42] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 10, p. 4900.

[43] Pearl Harbor Attack: Hearings Before the Joint Committee On the Investigation of the Pearl Harbor Attack, Congress of the United States, Seventy-ninth Congress, First Session, Part 28, pp. 944, 945.

3 thoughts on “Prologue to Pearl Harbor: The Spy Flight that Wasn’t, Part I

  1. Nicely done, Dr. Bradsher!

    After reading this first installment, I find the line from “Cool Hand Luke” appropriate: “What we got here is a failure to communicate.”

    While conducting research into the disappearance of Amelia Earhart, I have come across many of the same documents you cite in this essay. I was looking for Japanese military radio messages captured by the Navy’s OP-20 G and the Army’s SIG. I was hoping these messages might have some clues to Earhart or of the July 1938 disappearance of the China Clipper.

    Since your topic is a “Prologue to Pearl Harbor,” the following comments seem appropriate.

    According to Laurence Safford and others, OP- 20 G was routinely capturing Japanese Navy traffic from 1935 through February 1938. OP-20 G had the ability to completely translate those deciphered messages from Katakana to English (Blue Code). In February 1938, the Japanese began transmitting naval messages in a new code, commonly called JN 25. If OP20-G and the Navy had put their full resources to work translating all of the Blue Code messages up to the time the Japanese changed the code variants, ONI would have had specific knowledge of what military fortifications had been installed by the Japanese in the Mandates.

    I suspect those messages were captured by OP-20 G’s listening stations but never deciphered or translated until much later. Maybe they have never been deciphered and translated. Maybe they still languish somewhere – possibly in the far reaches of the Naval Support Center at Crane, Indiana.

    Several years ago, in one of several conversations I had with ex-Marine and NSA Historian Frederick Parker, he told me all pre-war Japanese military messages were eventually decoded in a 1945-46 project. Since this was pre-NSA, I am assuming this must have been a Navy project. But I am not sure. Mr. Parker said some of those message translations were used in his later classified research monographs. Parker’s monographs have since been declassified but I have been unable to locate the 1945 and 1946 translations. Robert J. Hanyok, an NSA Historian writing “Catching the Fox Unaware,” in the autumn 2008 Naval War College Review also mentions the 1945-6 project in which all prewar Japanese military messages were translated. It would seem since both men shared the same employer, it’s quite possible NSA later took possession of these records from the Navy.

    I am aware many of the Japanese Blue Code and JN 25 Code messages were referenced in the Pearl Harbor hearings. Therefore, as late as 1945, the Navy knew where those messages were archived. I still have difficulty believing Japanese military messages captured by our listening stations throughout the Pacific from 1937, 1938, and 1939 have been destroyed. Yet, I have been unable to locate where they are stored. Could you shed some light on my dilemma? At the least, it would be an important project since I believe the Japanese transmitted many messages concerning the discovery, detention, and location of Amelia Earhart in 1937 and 1938.

    Before the war, the first variants of JN 25 also called AN1 stumped OP-20G and SIG. On rare occasions, the Japanese used a new code Navy codebreakers described as the “Admiral’s Code” or “Fleet Code.” It never received much attention except by Joe Rochefort in Hawaii. Also before the war, the Army, (SIG) and Navy (OP-20G) had known Great Britain was working on decrypting JN 25. Neither country wanted to share their limited successes. Laurence Safford, the head of OP-20G mistrusted the Brits and probably rightfully so. Begrudgingly, the two sides met in Singapore before the war. OP-20 G discovered the Brits had dismantled about 12 to 13 percent of JN 25 but it was a different subset than the 12 to 13 percent broken by OP-20 G and SIG. Each side went away from the meeting with new code breaking possibilities. Sadly, after this meeting, there was little code breaking cooperation between the two countries until well into the war.

    As war loomed, the Japanese began tweaking JN 25 transmission making them that much more difficult to decipher. Because of manpower limitations, competition between Navy Communications, ONI, SIG, and failure by top commanders to realize the importance of codebreaking, a decision was made to rely on traffic analysis instead of code breaking until the war necessitated a change of attitude.

    Since traffic analysis has not been adequately explained, please allow me to inform the readers that traffic analysis consisted of nothing more than reading the headers and endings of Japanese messages and an occasional known subset in the message. Since OP-20G knew the standard coded terms the Japanese used for date, time, known ships, and that some of the code was repeated and common to all messages, OP-20 G learned to identify Japanese military locations; it then became much simpler to guesstimate what the Japanese message might entail. For example, if a header on a captured message in JN 25 with a known date, mentioned Yokosuka, and named a known coded term for a certain ship, and then mentioned Sasebo, It would be assumed that ship was proceeding from the naval base at Yokosuka to the Navy base at Sasebo.

    Depending on a pair of B-24’s overflight of the Marshall Islands and Truk to give the United States current intelligence on Japanese activities in the Mandates seems incredibly naïve. When you consider the disregard to diplomatic messages being sent to Tokyo by the Japanese Consulate in Honolulu in the weeks before December 7th, it’s no wonder there were Pearl Harbor Hearings.

    With that said, I look forward to your second installment.

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