2200: BBC ‘the dice are on the table’

Resistance member setting an explosive charge on a railway line.
Resistance member setting an explosive charge on a railway line.

Andre Heintz was a member of the French Resistance:

In early May 1944, my leader’s wife came to the school where I was teaching. She made me learn six sentences by heart, and also gave me their meanings. The messages would be broadcast just before the invasion, giving us a sign to start our acts of sabotage.

It seemed an awfully long time between the beginning of May and 1 June, when the first message was finally broadcast, signalling that the invasion would happen within the next week. That Sunday, 4 June, I went to a party at a friend’s house. As I stood there with people dancing all around me, I had this strange feeling that I was like a little god, because I could see into the future. I wanted to warn all my friends to go into hiding, but of course I couldn’t say anything, not even to my parents, because I was sworn to secrecy. I stood there wondering how many of my friends would survive.

The next day, Monday 5 June, we knew that something would happen soon, because the train from Paris didn’t reach Caen – the lines had been sabotaged. That evening I heard two messages – ‘the dice are on the table’, meaning we should sabotage railway lines; and ‘it’s hot in Suez’, meaning we should attack telephone lines.

Read the whole of his story on BBC People’s War

Get a full illustrated history of D-Day and the Normandy campaign, explore hundreds of contemporary images in the iPad App Overlord. The free iBook US Forces on D-Day provides a sample.

Germans seek more from their agent in Britain

German Military Intelligence had built up a remarkably detailed picture of British army units preparing for the Invasion of Europe.
German Military Intelligence had built up a remarkably detailed picture of British army units, including Australians, Canadians, Poles and New Zealanders, preparing for the Invasion of Europe.

Since 1942 German Intelligence had been receiving valuable intelligence from their man in Britain. The fanatical fascist, a Spanish Government official, had volunteered to work for them. After the initial information they received from him had proved credible, in 1942 they had instructed him to try to move to Britain. He got a posting to Britain. The Germans had then supplied him with a radio so he could transmit his findings directly to them, rather than posting them to Portugal.

The Germans knew him as ARABAL and he had proved incredibly useful, building up a string of contacts and other spies around Britain who reported to him. In Glasgow, Scotland, in the north of Britain, was Carlos, a Venezulean student, codename BENEDICT. He was ideally placed to watch the shipping movements and troops coming in from the United States.

He had also proved very valuable in reporting on the large numbers of troops that stayed in Scotland. They were not all sent down to the Channel Coast. From this the Germans had learnt that there would probably be an invasion of Norway launched from Scotland. They had been able to confirm this by listening to radio messages sent by Polish and American troops stationed in Scotland.

Now they received further confirmation as he reported on a local amphibious troop exercise, which ARABAL reported by radio to Germany:

. . . .V BENEDICT, UNDERTAKING ARABAL 10/5 from England via FELIPE: . . . . I estimate that up to 1100 hours more than a bde. of the div. had landed. Landing of troops was continued in a similar way.

Apart from the transports which brought the landing craft I was able to see another 10 transports, which lay in the neighbourhood and were doubtless connected with the exercise. One of these transports flew the flag WHITESIGN (sic) had a remarkably large number of aerials on board and continually sent light signals with searchlights to the shore.

The exercise lasted until the 11/5.

General impression gained by the VM on the basis of what he ascertained during the exercises and former information about this division is that it is intended for action in Norway as the division is continually receiving training in mountain warfare and all its equipment points to the probability of its going into action in northern regions. Have taken all measures to continue to watch every movement of transport fleet and troops.

This was just what the Germans wanted to hear. Hitler had already transferred troops to Norway on the basis of this information. Now they instructed ARABAL to get more information about the different units in the Allied Army:

It is to be assumed that the forces which will be engaged in the invasion operation will be divided into several independent armies, British and U.S. It would be of the greatest interest to know how many armies there will be and how many have already been formed. Headquarters and names of the commanders of each Army as well as their composition, i .e. , corps and divisions under command, the objectives assigned to each army.

Joan Pujol Garcia, better known to the Germans as ARABAL and to the British as GARBO.
Juan Pujol Garcia, better known to the Germans as ARABAL and to the British as GARBO.

ARABAL was delighted to hear this, because that was exactly what his British friends wanted him to do anyway. ARABAL is better known today by his British code name GARBO. He was the double agent who was feeding false information directly to German intelligence. BENEDICT was a complete work of fiction, as were the large army in Scotland about to invade Norway, and the even larger First US Army Group, FUSAG, supposedly commanded by Patton, who would launch a second invasion after the Normandy landings.

See Juan Pujol Garcia: Operation Garbo: The Personal Story of the Most Successful Spy of World War II and Roger Hesketh: Fortitude: The D-Day Deception Campaign.

Read more about GARBO at the Security Service, MI5

Landing craft that the Germans believed were waiting in the south east of England for the second invasion of Europe, to come weeks after the Normandy landings. In fact they were dummies.
Landing craft that the Germans believed were waiting in the south east of England for the second invasion of Europe, to come weeks after the Normandy landings. In fact they were dummies.

Officer’s sacrifice as Japanese march towards India

The Campaign in North and Central Burma February 1944 - August 1945: A well armed patrol of American led Burmese guerillas crossing a river in central Burma.
The Campaign in North and Central Burma February 1944 – August 1945: A well armed patrol of American led Burmese guerillas crossing a river in central Burma.

Major Hugh Seagrim was the leader of a small group of officers, the Special Operations Executive’s Force 136, working behind the lines in Burma. He had been responsible for bringing the Burmese nationalist leader Aung San (father of Aung San Suu Kyi) into talks with the British military. In the jungle of Burma he worked with Karen tribesmen to resist the Japanese occupation, leading sabotage on Japanese communications. The work of Force 136 featured in the fictional ‘Bridge on the River Kwai’.

However the Japanese soon learnt that British officers were involved in these operations and set about hunting them down. The impact of the Japanese hunt on the local people led Major Seagrim to give himself up on 15th March 1944. He was to earn the highest award for bravery for an action not involving direct combat, the George Cross:

Awarded the George Cross for most conspicuous gallantry in carrying out hazardous work in a very brave manner. Major Seagrim was the leader of a party which included two other British and one Karen officer working in the Karen Hills of Burma. By the end of 1943 the Japanese had learned of this party who then commenced a campaign of arrests and torture to determine their whereabouts. In February 1944 the other two British officers were ambushed and killed but Major Seagrim and the Karen officer escaped.

The Japanese then arrested 270 Karens and tortured and killed many of them but still they continued to support Major Seagrim. To end further suffering to the Karens, Seagrim surrendered himself to the Japanese on 15th March 1944. He was taken to Rangoon and together with eight others he was sentenced to death. He pleaded that the others were following his orders and as such they should be spared, but they were determined to die with him and were all executed.

There can hardly be a finer example of self-sacrifice and bravery than that exhibited by this officer who in cold blood deliberately gave himself up to save others, knowing well what his fate was likely to be at the hands of the enemy.

Major Hugh Seagrim, awarded a posthumous GC.
Major Hugh Seagrim, awarded a posthumous GC.

His brother, Major Derek Seagrim, had been awarded a posthumous Victoria Cross for his attack on the Mareth Line in Italy just a year before. There is a full account of the Seagrim brothers at britishmilitaryhistory.

Meanwhile the Japanese were marching in force on India. Lieutenant Walton of the Frontier Rifles was out on reconnaissance and was able to make this report on his observations from the banks of the River Chindwin on the 15th March:

At about 18.30 hours I saw men going north up the bank to collect boats, which were spaced at approximately twenty—yard intervals along the bank.They brought them down to the river.

These boats were approximately eight feet long and four feet wide with sharp prows. After darkness fell sections of six boats were brought together, lashed with bamboos and then lengths of decking placed on top.

Various sections were then joined together and one end fixed to the bank on the eastern side.The other end was allowed to swing with the current across the river until it hit the western bank, a distance of approximately 300 yards.

Almost immediately a number of men crossed the bridge with ammunition boxes and these were followed by bullocks, horses, ponies and more bullocks. The ponies were seen to be carrying what looked like dismantled mountain guns.These were followed by approximately 100 men carrying white and green boxes, and each man made at least two journeys.

This traffic continued to my knowledge until approximately 02.00 hours [on the 16th], and almost certainly until daylight. As daylight broke, a motor boat dragged the far end of the bridge up stream back to the far bank, where it was dismantled, the decking removed and the boats taken upstream and dispersed along the river bank. As soon as daylight came all noise and most movement ceased.

See Leslie Edwards: Kohima: The Furthest Battle.

This was the progress of the Japanese 132 Division, marching across Burma carrying all their own supplies through the jungles and over the mountains. The explosive last push of Japanese expansion was about to begin.

A view of the river after the British advance later in the year. A Bailey bridge over the Chindwin River near Kalewa, December 1944.
A view of the river after the British advance later in the year. A Bailey bridge over the Chindwin River near Kalewa, December 1944.

Bomber Command smashes secret Nazi weapons site

: Boeing B-17F formation over Schweinfurt, Germany, on Aug. 17, 1943.
Boeing B-17F formation over Schweinfurt, Germany, on Aug. 17, 1943.
Aerial views of V2 Rocket Sites at Peenemunde
Aerial views of V2 Rocket Sites at Peenemunde
Aerial reconnaissance view of the V1 launching ramps at the Luftwaffe Test Installation, Peenemunde West, Usedom Island, Germany, showing a Fiesler Fi 103 flying bomb positioned on its ramp (arrowed). This was the photograph from which Flight Officer Constance Babington-Smith, a photographic interpreter at the Allied Central Interpretation Unit, RAF Medmenham, Buckinghamshire, confirmed the existence of the V1. The sortie was carried out by a Mosquito of No. 540 Squadron flown by Squadron Leader J R H Merifield and his navigator Flying Officer W N Whalley.
Aerial reconnaissance view of the V1 launching ramps at the Luftwaffe Test Installation, Peenemunde West, Usedom Island, Germany, showing a Fiesler Fi 103 flying bomb positioned on its ramp (arrowed). This was the photograph from which Flight Officer Constance Babington-Smith, a photographic interpreter at the Allied Central Interpretation Unit, RAF Medmenham, Buckinghamshire, confirmed the existence of the V1. The sortie was carried out by a Mosquito of No. 540 Squadron flown by Squadron Leader J R H Merifield and his navigator Flying Officer W N Whalley.

On 17th August as the USAAF headed out for their daylight raid on Schweinfurt, the crews of RAF Bomber Command were being briefed for their raid that night. This time they would be flying in moonlight, which was usually avoided, and the Intelligence Officers stressed the importance of the target that required this.

Crews were told that they would be bombing a factory building new radar controlled night fighters at Peenemunde. It was obviously in their interests to destroy such a target. It had ben given such a priority that not only would they be bombing in moonlight but they would be doing so from half the usual height.

Amongst those leading this raid was Cliff Alabaster, who had survived being shot down by ‘friendly fire’ in 1941. He now a hugely experienced navigator and was, very unusually, captain of his Pathfinder aircraft.

In fact the true purpose of the raid was to destroy the V-2 rocket programme. The fact that British intelligence even knew of its existence had to remain secret. The bomber crews could not be put fully in the picture, crews that survived being shot down would inevitably be interrogated about their targets.

Arguably this was one of the most important bombing raids of the war. Had the RAF not possessed the capability for such mass destruction by this stage in the war, the V-2 rocket programme against Britain would have got underway long before the invasion of France.

A diversionary raid to Berlin by Mosquitoes was also despatched that night in an attempt to draw off the German night fighters. It was not wholly successful, as the relatively inexperienced Jack Currie, piloting a Lancaster, was to discover:

We got DV222 George Two off the ground at twenty-three minutes to ten and, washed in the unaccustomed moonlight, set course east. Tail winds brought us early to our check-point in the Baltic, and I throttled back to lose time as we came to Rugen Island, north-west of the target.

Peenemunde lay starkly lighted by the moon, marked by green TIs, while a master-bomber circled, marshalling the attack. At thirty-four minutes after midnight I set George Two’s nose at the target on a time and—distance run, and Larry dropped the bombs from 9000 feet; a 4000 pounder, six 1000 pounders, and two 500 pounders. A billowing smoke screen partially obscured the target, but did not deter his aim. We swung right on to 290° true, against a forty-knot headwind, and climbed hard.

We had reached 18,000 feet near Stralsund, when the first fighter appeared, and the longest ten minutes I had known began. The ‘boozer’ light, flashing on my panel, gave the first warning that we were being followed, and then Lanham picked him up from the rear turret. ‘Fighter, fighter. Stand by to cork-screw port.’ ‘Standing by.’ ‘Mid—upper from rear-gunner. He’s at seven o’clock low. There may be a pair. I’ll look after this one, you watch out for the other.’ ‘Okay, Charlie.‘ ‘Prepare to cork-screw port… cork-screw port… go.’ ‘Going port.’

I rolled George Two sharply left, and dropped the nose. I let her go through ten degrees before pulling to the right and up, levelled as she passed back through the homeward heading, dived through another ten degrees right, climbed her back to port through twenty degrees.

Charlie kept the patter going, giving me the fighter’s distance and position, then: ‘Foxed him, Jack. He’s holding off on the starboard quarter. Now he‘s going low astern. He‘s out of range. Stand by.’ George Protheroe, slowly rotating the mid-upper turret, pressed his microphone switch. ‘Another fighter, skipper, four o’clock high, six hundred yards. It’s an Me 2l0.’

Charlie broke in. ‘Watch him, George. Here comes number one. Cork-screw starboard… go.’ ‘Going starboard.’ Between us, the gunners and I evaded four attacks. There were eleven degrees of frost at our height, but, after throwing George Two about the sky for a few minutes, I was sweating like a horse, and my muscles were aching.

While one fighter attacked, the other held off, content to retain one gunner’s attention. They were never in Lanham’s field of fire, and the mid-upper guns stayed silent.

A feeling of despair began to crawl into my mind; inevitably I would become exhausted and the fighters’ shells would rip George Two to shreds. They could afford to take their time. Perhaps the sadistic bastards were just playing with us. I pressed my back against the armour-plate behind me, and wondered what protection it would give. Messerschmitt, I thought, get it over with.

Turning automatically into another cork-screw to the left, I looked over my shoulder, down the length of the port wing. There he was, less than a hundred yards away, and converging, trying to bring his guns to bear. I saw a helmeted head in the cockpit, and a surge of anger pushed my lethargy away.

I stared at the German pilot. You’re no good, I thought. You’re a damned poor shot and a bloody awful pilot. Why the hell doesn’t the mid-upper fire? I snapped the mike switch on. ‘For Christ’s sake, George, shoot that bastard down!’ At once, the guns chattered, and a stream of orange sparks curved slowly down and through the fighter’s nose. He rolled over on his back, and dived straight down, disappearing into a sheet of stratus thousands of feet below.

‘I think you got him. Where’s the other one?’ Lanham answered from the rear turret. ‘Falling back astern. He’s clearing off. Good shooting, George!’ I agreed. ‘Yes, well done, George! What kept you?’ ‘Sorry, skipper. I had my sights on him all the time. I think I just forgot to shoot.’

I sat relaxed and let the relief run over me. George Two sailed on securely in the cold and moonlit night. I thought about the little Welsh mid-upper gunner, barely eighteen years old, rigid in his turret through the combat, unable to press the triggers until he heard my angry shout.

The Peenemunde raid, on which nearly 600 bombers were deployed, and forty lost, including the ‘A’ Flight Commander from Wickenby, was perhaps the most important on which we were engaged. We later learned that it delayed the enemy’s V-bomb attacks on England by six crucial months.

See Jack Currie: Lancaster Target.

Aerial reconnaissance photograph of the Rocket Research Establishment at Peenemunde, Usedom Island, Germany, taken by a De Havilland Mosquito PR Mark IX of No. 540 Squadron RAF, using a Type F.52 (36") vertical camera. This view shows the concentration of bomb craters on the airfield and damage to technical buildings of the Luftwaffe Test Facility, Peenemunde West, after the raid by Bomber Command on 17/18 August 1943.
Aerial reconnaissance photograph of the Rocket Research Establishment at Peenemunde, Usedom Island, Germany, taken by a De Havilland Mosquito PR Mark IX of No. 540 Squadron RAF, using a Type F.52 (36″) vertical camera. This view shows the concentration of bomb craters on the airfield and damage to technical buildings of the Luftwaffe Test Facility, Peenemunde West, after the raid by Bomber Command on 17/18 August 1943.
Aerial reconnaissance photograph of the Rocket Research Establishment at Peenemunde, Usedom Island, Germany, taken by a De Havilland Mosquito PR Mark IX of No. 540 Squadron RAF, using a Type F.52 (36") vertical camera. This view shows the devastated Karlshagen Housing Estate, which accommodated the Establishment's married staff and their families, after the air raid by Bomber Command on 17/18 August 1943. Of the 2,500 dwellings on the estate, only 72 survived.
Aerial reconnaissance photograph of the Rocket Research Establishment at Peenemunde, Usedom Island, Germany, taken by a De Havilland Mosquito PR Mark IX of No. 540 Squadron RAF, using a Type F.52 (36″) vertical camera. This view shows the devastated Karlshagen Housing Estate, which accommodated the Establishment’s married staff and their families, after the air raid by Bomber Command on 17/18 August 1943. Of the 2,500 dwellings on the estate, only 72 survived.

Dropping into occupied France by moonlight

The Halifax was used to drop parachutists on covert missions.  Low-level 'beat-up'. A Halifax II, JB911/KN-X of No 77 Squadron roars low over an audience of appreciative 'erks' during air tests at Elvington, Yorkshire, July 1943.
The Halifax was used to drop parachutists on covert missions.
Low-level ‘beat-up’. A Halifax II, JB911/KN-X of No 77 Squadron roars low over an audience of appreciative ‘erks’ during air tests at Elvington, Yorkshire, July 1943.
The Secretary of State for Air, Sir Archibald Sinclair (in civilian raincoat), accompanied by the Commanding Officer of No. 161 (Special Duties) Squadron RAF, Wing Commander P C Pickard, talking to Flying Officers Broadley and Cocker in front of their Lockheed Hudson during his visit to Tempsford, Bedfordshire. A noted Westland Lysander pilot of the Squadron, Fg Off J A McCairns, is standing extreme left.
The Secretary of State for Air, Sir Archibald Sinclair (in civilian raincoat), accompanied by the Commanding Officer of No. 161 (Special Duties) Squadron RAF, Wing Commander P C Pickard, talking to Flying Officers Broadley and Cocker in front of their Lockheed Hudson during his visit to Tempsford, Bedfordshire. A noted Westland Lysander pilot of the Squadron, Fg Off J A McCairns, is standing extreme left.

The dangerous business of dropping SOE agents into France continued, taking advantage of the periods of full moon to locate the remote airfields and drop zones. All too few of those who dropped or were landed lived long enough to tell their tale. Hugh Dormer was one of those who did.

Dormer was not going in to assist the French Resistance but to make a direct sabotage attack. He had already led one mission – from which he narrowly escaped and then left France by walking over the Pyrenees mountains. Despite feeling like a “hunted rat” whilst in Paris during that mission he had agreed to go out again shortly after to returning to Britain in June 1943.

When he left a remote airfield “somewhere in Britain” this time he knew what to expect:

August 16th

We left for the aerodrome in the stillness of a lovely summer’s evening, while the boys playing in the village street outside paused to stare curiously at the car as it passed.

Everything ended up in the usual mad last minute hurry and I remembered only the words of one of the Stonor martyrs: ‘If I have courage, it is because I have not the time to think whether I have courage or no.’.

Once again out to the roaring engines on the tarmac, the slipstream tearing one’s words away, the last handshake and the setting sun and the banging of the fuselage door behind. Who could have foretold that out of the six men who climbed up into the plane that night four were already marked for death and would never return?

Like Mahomet’s coffin we were now suspended for the next four hours between the two worlds. We stretched ourselves out in the dark interior of the bomber which every second flew deeper over enemy territory.

The door leading into the pilot’s cabin was open and through the windows of the cockpit the moon stared in, illuminating everything like daylight. Its round disc swung in the window with our changing course, like the night stars behind the masts of a ship at sea.

At intervals the pilot would climb and then dive down steeply with everything shuddering and vibrating so as to confuse the flak and radio-location posts beneath us. Speech was impossible in that noise. I was having a bad attack of earache again and even I found the whole journey much more unnerving than last time. Perhaps it was that now one knew the ordeal one was facing, and the price on one’s head, and had lost that courage which comes from ignorance.

I lay in the dark and thought of all those people sleeping in their beds back in England and how serenely oblivious they were of the dangers we were facing. So secret are these operations that only the handful of people back in the aerodrome knew anything at all of what was happening. Yet I did not grudge them the snugness of their sheets, but only promised that, if ever I returned to England by the grace of God and lay again in a warm bed on a cold night, I would remember those who would be up and working outside at that same hour in the full moon.

I thought of all those people whom I had ever befriended in my life and who I knew wished me well, and as always in danger and hardship their prayers were a great encouragement and support. And I thought too how strange it would be, if one could look into the future a few days, even a few hours ahead, and see what it held for each one of us, lying there in the darkness of the fuselage. And then again the spirit faltered and one wished to be returning home.

On the way we dropped some containers to a reception committee and it was an extraordinary experience to look down at the line of red lights and the figures running across the field, as the parachutes with their weapons and explosives went down in the moonlight into France against the time of her great uprising on that unbelievable day for which so many had been working and waiting those long years.

The hole was now uncovered and I gazed down at the fields and roads gliding beneath in the pale light of the moon with here and there the dark patches of the woods. The pilot was searching for his lights, then seeing them he banked steeply and turned for the run-in.

The light opposite me flashed to red and I swung my legs into the hole. In a few seconds I should have jumped again down into that prison of Europe and the Halifax would be turning home for England. One will never forget the tension of that moment as the parachutist listens to the slowing down of the engines to stalling speed and then the light flashes to green and one is through the hole and into the rush of the slipstream, then drifting high over the earth in the peace of the moonlight. All those weeks of apprehension and the nightmares which burden one’s sleeping dreams are over, and the work has begun.

See Hugh Dormer’s Diaries. See Air Force Magazine for much more on the ‘Moon Squadrons’.

 Lysander Mark IIIA (SD), V9673 'MA-J', of No.161 (Special Duties) Squadron RAF on the ground at Tempsford, Bedfordshire. This aircraft was flown by Squadron Leader Hugh Verity on twenty missions to occupied France in 1943 to drop and pick up SOE and Resistance personnel.
Lysander Mark IIIA (SD), V9673 ‘MA-J’, of No.161 (Special Duties) Squadron RAF on the ground at Tempsford, Bedfordshire. This aircraft was flown by Squadron Leader Hugh Verity on twenty missions to occupied France in 1943 to drop and pick up SOE and Resistance personnel.
The Secretary of State for Air, Sir Archibald Sinclair meets with pilots of 'C' (Polish) Flight, No. 138 (Special Duties) Squadron RAF, formerly the 300 Polish Bomber Squadron, during his visit to Tempsford, Bedfordshire.
The Secretary of State for Air, Sir Archibald Sinclair meets with pilots of ‘C’ (Polish) Flight, No. 138 (Special Duties) Squadron RAF, formerly the 300 Polish Bomber Squadron, during his visit to Tempsford, Bedfordshire.

Manhattan Project calculates the effects of The Gadget

In March 1943, DuPont began construction of a plutonium plant on a 112-acre (0.5 km2) site at Oak Ridge. Workers load uranium slugs into the X-10 Graphite Reactor.
In March 1943, DuPont began construction of a plutonium plant on a 112-acre (0.5 km2) site at Oak Ridge. Workers load uranium slugs into the X-10 Graphite Reactor.

The 24th April 1943 saw an important milestone in the the “Manhattan Project”. “Manhattan District” had originally just been the U.S Army code name for their involvement in aspects of the project. This was the name that was gradually adopted to refer to the whole official programme for the “Development of Substitute Materials”, the atomic weapons programme, designated “Tube Alloys” by the British.

From very modest beginnings that had evolved from the the first theoretical understanding of the power of atomic energy the programme, which had only begun in 1941, had developed into a major industry. During the course of the war it would cost $2 billion – around $26 billion in 2013 values – and employed over 130,000 people in a wide variety of sites around the United States. Very few of these people knew what they were actually working on.

Only a small group of individuals at the top had a complete overview of the work they were doing. Between 15th-24th April they met in conference to discuss the outcomes of the different strands of research. They were now in a position to understand how much nuclear material they could produce and what the destructive power of a potential weapon was likely to be. The testing of a real atomic weapon device or “Gadget” still remained a long way off:

OUTLINE OF PRESENT KNOWLEDGE

Robert Oppenheimer

Energy Release: The destructive effect of the gadget is due to radiative effects and the shock wave generated by the explosion. . The shock wave effect seems to extend over the biggest area and would be, therefore, most important. The area devastated by the shock wave is proportional to the 2/3 power of the energy release and may be simply calculated by comparing the energy release with that of TNT. If the reaction would go to completion, then 50 kg of [isotope] 25 would be equivalent to 10 tons of TNT. Actually it is very difficult to obtain a large percentage of the potential energy release.

Detonation: The second major difficulty facing us is connected with the question of detonation. . It is important that no neutron should start a premature chain reaction. . . Possible sources of neutrons are 1) Cosmic ray neutrons . . . and 2) Spontaneous fission neutrons. . .

EXPECTED DAMAGE OF THE GADGET

Hans Bethe

Comparison with TNT: The most striking difference between the gadget and a TNT charge is in the temperatures generated. The latter yields temperatures of a few thousand degrees whereas the former pushes the temperature as high as [tens of millions of degrees]. . . .

The actual damage depends much on the objective. Houses begin to be smashed under shocks of 1/10 to 1/5 of an atmosphere. For objects such as steel supported buildings and machinery, greater pressures are required and the duration of the shock is very important. If the duration of the pressure pulse is smaller than the natural vibration period of the structure, the integral of the pressure over the duration T of the impulse is significant for the damage. If the pulse lasts for several vibration periods. the peak pressure is the important quantity. . . .

Other Damage: The neutrons emitted from the gadget will diffuse through the air over a distance of 1 to 2 km, nearly independent of the energy release. Over this region, their intensity will be sufficient to kill a person,

The effect of the radioactive fission products depends entirely on the distance to which they are carried by the wind. If 1 kg of fission products is distributed uniformly over an area of about 100 square miles, the radioactivity during the first day will represent a lethal dose (=500 R units): after a few days, only about 10 R units per day are emitted, If the material is more widely distributed by the wind, the effects of the radioactivity will be relatively minor.

See The Atomic Archive for original documents.

The Chindits march into the Burmese jungle

Chindits with their mules carrying supplies make their way through the jungle.
Chindits with their mules carrying supplies make their way through the jungle.

In Burma, now occupied by the Japanese, the British were experimenting with unconventional methods of warfare. Colonel Orde Wingate had won support for the development of a deep penetration guerrilla force that would march far into the jungle, way behind the front line. There they would disrupt the enemy’s lines of communication by blowing up railway lines, as well as attacking Japanese troops. The new force soon became christened ‘Chindits’, after mythical Burmese creatures.

The conditions the troops were expected to live in were arduous enough. However, the problem of resupplying such troops by air was also experimental, and was to lead to further privations. The first column set off into the jungle in late February 1943 and received their first parachute drop of supplies in early March. Harold James was a nineteen year old officer on his first military operation:

The dropping area was strewn with ration tins, parachutes and mule fodder, and the men soon got to work collecting the stores. Burmese from the nearest village were called in to help, and in return were given the parachutes which they greatly prized, cloth being a scarcity. We soon learned that valuable information could often be obtained for a piece of parachute. The Gurkhas made handerchiefs and ration bags for themselves, and lanyards from the cords.

Four tins were dropped with each parachute, padded with a shock absorber fastened by thick webbing – although this did not always work if the parachute should break loose. The four tins could conveniently be loaded each side of a mule, allowing extra rations to be carried as reserve, and, as on this occasion, the supplies could be easily transported from the dropping zone to our camp for distribution to the men.

The hard scale daily ration laid down was:

Shakapura biscuits l2oz
Cheese 2oz
Milk powder 1oz
Raisins and almonds 9oz
Tea 3/4 oz
Sugar 4oz
Acid drops or chocolate 1oz
Salt 1/2oz
Cigarettes 2 packets of 10
Matches 1 box

To imagine that men could keep fit on a ration of this nature for three months of marching through very rough country, fighting, physically and mentally extended, is beyond belief, and would seem to show a definite lack of imagination in planning the ration menu.

But the expedition was heading into unexplored areas of logistics, and presented problems which had to be solved by guesswork before hard experience could produce the correct results.

There was no meat, although tins of corned beef were dropped later, and on occasion corned mutton for the Gurkhas. But it was bulky, and went bad quite quickly, so had to be eaten more or less in one sitting. The parachute ration was supposed to be supplemented from local produce, which often proved impracticable.

With over 300 mouths to feed, very few villages could provide more than a few mouthfuls of rice per person, and the odd chicken or egg. Some columns were lucky in coming across an extra friendly village which would be more helpful – but seldom more than once during the expedition.

The idea behind the rations selected was that they contained nothing that required cooking, except water for tea, since it was expected that troops would not be able to count on more than twenty minutes for meals. In practice
we rarely had to rush our meals.

It was also assumed that supplies would be dropped regularly, which turned out, after the first two drops, to be
a false hope, not because of any shortage of aircraft, just that the enemy’s presence often made it impossible to pick and choose time and place. As a result, for most of the expedition, one day`s rations had to last at the very least for three, and too often much longer.

A great deal of will power was needed to limit the daily intake.

See Harold James: Across the Threshold of Battle

USS Indianapolis torpedoed – 900 men in the water

The U.S. Navy heavy cruiser USS Indianapolis (CA-35) underway in 1939. An Omaha-class light cruiser and several Clemson/Wickes-class "flushdeck" destroyers are visible in the background.
The U.S. Navy heavy cruiser USS Indianapolis (CA-35) underway in 1939. An Omaha-class light cruiser and several Clemson/Wickes-class “flushdeck” destroyers are visible in the background.

As soon as the Trinity nuclear test had been successfully concluded on the 16th July the USS Indianapolis had been despatched from Mare island, San Francisco to Tinian island in the mid Pacific. The heavy cruiser carried the Uranium that would arm the Little Boy bomb.

By 29th July she was en route back to the Philippines across the remotest reaches of the ocean. Her captain had discretion not to zig-zag and it may have made no difference that she was not.

A new study of the sinking published in 2018 reconstructs the events aboard the Japanese submarine I-58, captained by Hashimoto

I-58’s crew waited, breathless. The black shape on the horizon soon gathered itself into the shape of a triangle suspended in the moon’s silver light. But looking through the night periscope, Hashimoto still could not determine her class. Neither could he see the height of her mast in order to estimate the range. This lack of data opened the door to an array of possible mistakes, and his mind ticked through them all.

Without the range, course, and speed of the target, he could not make the proper calculations to obtain a hit. If the class of ship were known, he could estimate the speed by counting the target’s propeller blade frequency, but the hydrophones remained silent. And with the target pointed directly at him, its hull was masking sonar sounds.

He would have to wait until the target was on a broader line of sight to ferret out its speed. Also, changes in the target’s speed and course could throw off Hashimoto’s aim, especially at night, so the moment of ring had to be determined in advance.

A whole kingdom of errors loomed. But if Hashimoto could keep them small and fire six torpedoes in a fanwise spread, he could ensure a hit. Even if he guessed wrong on one of the variables – or even if the target zigzagged, as it was almost sure to do.

A crisp demand interrupted his calculations: “Send us!” It was the suicide pilots. Hashimoto had been so preoccupied with his Type 95 torpedo calculations that he had not followed up on his earlier order for the kaiten. “Why can’t we be launched?” the pilots clamored.

Hashimoto understood their desire. The kaiten could steer to the target, regardless of its speed or course. But the touch-and-go, obscured visibility would make it difficult for the pilots to home in visually on the target over a period of tens of minutes.

To get a Type 95 torpedo hit, all he needed was a reasonable estimate of speed and range, along with one good bearing, and he could send his sh to their target. That was the better option here, so he decided not to use the kaiten unless the oxygen torpedoes failed to hit their mark.

Hashimoto put his eye to the scope again and saw the top of the triangle resolve into two distinct shapes. He could make out a large mast forward and estimated its height at ninety feet. His heartbeat quickened. She appeared to be a large cruiser, ten thousand tons or bigger. Now I-58’s hydrophones gurgled to life, announcing enemy propeller revolutions that were moderately high. Using visual observations, Hashimoto adjusted and put the target’s speed at twelve knots, course 260, range three thousand yards.

He alone could see all this. Without him, the crew could know nothing. As they awaited his word, straining in the deadly quiet, an exhilarating thought formed in his mind: We’ve got her.

Aboard I-58, a sonarman thought he heard the clinking of dishes.‘ Twenty-seven minutes had passed since I—58’s navigator spotted the enemy ship. It now became apparent that the target was approaching off the starboard bow. He ordered the torpedo director computer set to “green sixty degrees”——the torpedoes would turn sixty degrees starboard after launch.

The target closed the distance: twenty-five hundred yards… two thousand… fifteen hundred. “Stand by…” Hashimoto commanded in a loud voice. “Fire!” At two-second intervals, six torpedoes ejected from tubes carved into the sub’s forward hull, one tube after another until all six were away. A report came from the torpedo room: “All tubes fired and correct.”

It was about five minutes after midnight, and six warheads streaked toward the enemy warship in a lethal fan. Hashimoto snatched a look through the periscope, brought his boat on a course parallel to the target, and waited. Every minute seemed an age.

The Indianapolis was steaming straight ahead when she was hit by three Type 95 torpedoes from the Japanese submarine I-58 at 23:35. Some U.S accounts put the time at 00:14.

USS_Indianapolis-last_voyage_chart

Contrary to US Navy claims during the war and after, the Indianapolis was not observing radio silence because of the secrecy of her mission – she managed to transmit distress signals which were received by three separate US Navy monitoring stations, a matter that has only emerged from later de-classified documents. None of the three stations acted on the information. At 00:27 on 30 July, Indianapolis capsized and sank carrying around 300 men with her. The remainder of her 1,196 crew went into the water, only a limited number of lifeboats had been deployed and a minority of the men had life jackets.

Approximately 900 men now faced a hellish ordeal as they struggled to survive in the warm seas, with little or no water. They faced severe sun burn, dehydration, hypothermia – and sharks. Some have argued that the incident amounts to the largest single shark attack in human history. An account by the surviving Chief Medical Officer on board, Dr Lewis Haynes throws some light on the extent of the shark hazard:

I slowly walked down the side of the ship. Another kid came and said he didn’t have a jacket. I had an extra jacket and he put it on. We both jumped into the water which was covered with fuel oil. I wasn’t alone in the water. The hull was covered with people climbing down.

I didn’t want to get sucked down with the ship so I kicked my feet to get away. And then the ship rose up high. I thought it was going to come down and crush me. The ship kept leaning out away from me, the aft end rising up and leaning over as it stood up on its nose. The ship was still going forward at probably 3 or 4 knots. When it finally sank, it was over a hundred yards from me. Most of the survivors were strung out anywhere from half a mile to a mile behind the ship.

Suddenly the ship was gone and it was very quiet. It had only been 12 minutes since the torpedoes hit. We started to gather together. Being in the water wasn’t an unpleasant experience except that the black fuel oil got in your nose and eyes. We all looked the same, black oil all over – white eyes and red mouths. You couldn’t tell the doctor from the boat seamen. Soon everyone had swallowed fuel oil and gotten sick. Then everyone began vomiting.

At that time, I could have hidden but somebody yelled, ‘Is the doctor there?’ And I made myself known. From that point on – and that’s probably why I’m here today — I was kept so busy I had to keep going. But without any equipment, from that point on I became a coroner.

A lot of men were without life jackets. The kapok life jacket is designed with a space in the back. Those who had life jackets that were injured, you could put your arm through that space and pull them up on your hip and keep them out of the water. And the men were very good about doing this. Further more, those with jackets supported men without jackets. They held on the back of them, put their arms through there and held on floating in tandem.

When daylight came we began to get ourselves organized into a group and the leaders began to come out. When first light came we had between three and four hundred men in our group. I would guess that probably seven or eight hundred men made it out of the ship. I began to find the wounded and dead. The only way I could tell they were dead was to put my finger in their eye. If their pupils were dilated and they didn’t blink I assumed they were dead. We would then laboriously take off their life jacket and give it to men who didn’t have jackets. In the beginning I took off their dogtags, said The Lord’s Prayer, and let them go. Eventually, I got such an armful of dogtags I couldn’t hold them any longer. Even today, when I try to say The Lord’s Prayer or hear it, I simply lose it.

…The second night, which was Monday night, we had all the men put their arms through the life jacket of the man in front of him and we made a big mass so we could stay together. We kept the wounded and those who were sickest in the center of the pack and that was my territory. Some of the men could doze off and sleep for a few minutes. The next day we found a life ring. I could put one very sick man across it to support him.

There was nothing I could do but give advice, bury the dead, save the life jackets, and try to keep the men from drinking the salt water when we drifted out of the fuel oil. When the hot sun came out and we were in this crystal clear water, you were so thirsty you couldn’t believe it wasn’t good enough to drink. I had a hard time convincing the men that they shouldn’t drink. The real young ones – you take away their hope, you take away their water and food – they would drink salt water and then would go fast. I can remember striking men who were drinking water to try and stop them. They would get diarrhea, then get more dehydrated, then become very maniacal.

In the beginning, we tried to hold them and support them while they were thrashing around. And then we found we were losing a good man to get rid of one who had been bad and drank. As terrible as it may sound, towards the end when they did this, we shoved them away from the pack because we had to.

The water in that part of the Pacific was warm and good for swimming. But body temperature is over 98 and when you immerse someone up to their chin in that water for a couple of days, you’re going to chill him down. So at night we would tie everyone close together to stay warm. But they still had severe chills which led to fever and delirium.

On Tuesday night some guy began yelling, ‘There’s a Jap here and he’s trying to kill me.’ And then everybody started to fight. They were totally out of their minds. A lot of men were killed that night. A lot of men drowned. Overnight everybody untied themselves and got scattered in all directions. But you couldn’t blame the men. It was mass hysteria. You became wary of everyone. Till daylight came, you weren’t sure. When we got back together the next day there were a hell of a lot fewer.

I saw only one shark. I remember reaching out trying to grab hold of him. I thought maybe it would be food. However, when night came, things would bump against you in the dark or brush against your leg and you would wonder what it was. But honestly, in the entire 110 hours I was in the water I did not see a man attacked by a shark. However, the destroyers that picked up the bodies afterwards found a large number of those bodies. In the report I read 56 bodies were mutilated, Maybe the sharks were satisfied with the dead; they didn’t have to bite the living.

Their ordeal had been lengthened because the failure of the Indianapolis to arrive in the Philippines when expected was also not reported, and no search for the ship was ever undertaken. Instead they were spotted by chance at 10:25 on 2 August by a PV-1 Ventura on a routine patrol. They still had to spend the rest of the day in the water before help arrived:

It was Thursday [2 Aug] when the plane spotted us. By then we were in very bad shape. The kapok life jacket becomes waterlogged. It’s good for about 48 hours. We sunk lower down in the water and you had to think about keeping your face out of water. I knew we didn’t have very long to go. The men were semicomatose. We were all on the verge of dying when suddenly this plane flew over. I’m here today because someone on that plane had a sore neck. He went to fix the aerial and got a stiff neck and lay down in the blister underneath. While he was rubbing his neck he saw us.

The plane dropped life jackets with canisters of water but the canisters ruptured. Then a PBY [seaplane] showed up and dropped rubber life rafts. We put the sickest people aboard and the others hung around the side. I found a flask of water with a 1-ounce cup. I doled out the water, passing the cup down hand to hand. Not one man cheated and I know how thirsty they were.

Towards the end of the day, just before dark, I found a kit for making fresh water out of salt water. I tried to read the instructions, but couldn’t make sense of it or get it to work right. My product tasted like salt water and I didn’t want to take a chance so I threw it into the ocean. I then went to
pieces.

I watched the PBY circle and suddenly make an open-sea landing. This took an awful lot of guts. It hit, went back up in the air and splashed down again. I thought he’d crashed but he came taxiing back. I found out later he was taxiing around picking up the singles. If he hadn’t done this, I don’t think we would have survived. He stayed on the water during the night and turned his searchlight up into the sky so the Cecil J. Doyle (DE-368) could find us. The ship came right over and began picking us up.

See Lewis L. Haynes, “Survivor of the Indianapolis.” Navy Medicine 86, no.4 (Jul.-Aug. 1995)

I-58(II), modified B type 2 of submarine of the Imperial Japanese Navy, on trial run inside the Tokyo Bay.
I-58(II), modified B type 2 of submarine of the Imperial Japanese Navy, on trial run inside the Tokyo Bay.