Chapter 126 Volume 4 Chapter 16 Air Offensive

27th February 1942 Raid on Breneva A priceless prize An unresolved detail Flint's illustrious exploits Doubts about the accuracy of our bomber's bombing directed the bomber's device forward Oppo Hydrogen sulphide against New German Bombing Offensive Plans Slow Production of Hydrogen Sulphide The Role of Hydrogen Sulphide in the Anti-Submarine Campaign Air-to-Sea Search Radar A Orientation Device Shared with the Enemy Fighter's Attack Combat Carmen Huber line called window design Our hesitation about using this method Amazing achievement of this method. During the winter of 1941 our intelligence suspected that the Germans were using a new radar instrument for their anti-aircraft guns to determine the course and range of our aircraft.It is said that this instrument is like a huge bowl-shaped electric heater.Our spies, air listening equipment, aerial photography, etc., soon detected a series of stations along the northern coast of Europe, and one of them, probably the one with the new equipment, was set up at On Cape Antifère, not far from Le Havre.On December 3, 1941, the captain of a squadron of our aerial photographic reconnaissance unit accidentally visited our intelligence center and learned of what we suspected.The next day, he took the initiative to fly there and determined the location of the radio station.On December 5th he went out again and took an excellent and successful picture.Our scientists think that's exactly what they expected.Although the radio station is set on a cliff as high as 400 feet, there is a sandy beach nearby, which can be used as a landing ground for planes.A commando attack plan was then drawn up.

On the night of February 27, 1942, a snowy night, at midnight a paratroopers landed behind the German radio station on the top of the cliff and surrounded the defenders.The paratroopers were accompanied by a detachment of engineers receiving detailed instructions and an RAF radio engineer.They were ordered to dismantle and take away as much equipment as possible, to sketch or photograph the rest of the equipment, and, if possible, to capture a German operator.Although a timetable discrepancy reduced their overall work time from half an hour to only ten minutes, they completed all tasks.Most of the equipment was found, disassembled by firelight, and transported to the beach.The navy is waiting here to take the troop away.We thus possessed a major part of the key equipment of the German radar defense and obtained information which was of great advantage to our air offensive.

Our knowledge of German defenses gradually increased in 1942, aided by the rapid expansion of spy networks designed to gather information on radar, and by information brought in from occupied countries by friendly neutrals.When spies or friendly neutrals are mentioned, the Belgians should be justly singled out. In 1942 they provided 80 per cent of all intelligence on this subject, including a crucial map.The map was stolen from the commander of the German searchlight and radar units within the route of the two theaters north of the German night fighters in Belgium.With this map, and other intelligence, it was possible for our experts to unravel the mysteries of the German air defense system, and by the end of the year we knew not only how the hostile system operated, but also how to counter it.

However, there was one detail we didn't know, and didn't find out until many months later.By the end of the year, Professor Lindemann, now Lord Cherwell, told me that the Germans had installed a new radar installation in their night fighters.Nothing was known about this radar device, except that it was called the Flint, and that it was designed to track our bombers.Before we launch our aerial offensive, we must learn more about this device.On the night of December 2, 1942, we sent an aircraft of the 192nd Squadron as a decoy target.The aircraft was repeatedly attacked by an enemy night fighter that emitted radio waves from radiating flint.Almost all crew members were hit.The special technician who listened to the radiation waves suffered serious head injuries, but was still making accurate observations.The radio operator, though critically injured, parachuted down over Ramsgate, thus saving his life and his invaluable observations.The rest of the crew drove the plane to the sea and landed on the water, because the parts on the plane were too damaged to land at the airport.They were rescued by a small boat from Dill.In this way, the gap in our knowledge of Germany's night defenses was filled.

Already in 1940 Professor Lindemann had begun to make me doubt the accuracy of our bombing, so in 1941 I ordered his Statistical Office to conduct an investigation at Bomber Command.The results of the investigation confirmed our fears.We learned that although Bomber Command thought it had found the target, two-thirds of the crew actually failed to hit within five miles of the target.Aerial photography also showed how little damage we inflicted on the enemy.The crew seemed to know this, too, and were disheartened at the prospect of too little success.Unless we improve on this front, it does not seem to be of much use to continue the night bombing.On September 3, 1941, I issued the following memorandum:

Prime Minister to Chief of Air Staff The accompanying document (Lord Cherwell's report on the results of the June and July bombing of Germany) is of such importance that it appears to be drawing your urgent attention.I await your advice on steps to take. Several methods of guiding our bombers to their targets with the aid of radio have been proposed before, but until we realize how inaccurate our bombing is, there seems to be no reason to study such complex problems.We have now focused our attention on these issues.We have worked on a method called forwarding in the past, in which radio waves are sent simultaneously from three stations in the UK that are far apart from each other.By knowing exactly when the radio waves arrive at an aircraft, it is possible to determine the aircraft's position within a mile of the target.This is an improvement which we employed on a large scale about ten days after the raid on Breneva.With this we hit most of the targets in the Ruhr area, but we were not able to penetrate far enough into Germany.Lübeck and Rostock were also bombed by us during this period, but not by advancing.A similar method, called Opal, is much more accurate.

However, in order to use this method, the bomber must fly in a straight line for a considerable period of time, and there is a great risk of being attacked by anti-aircraft fire.And, as with this approach, the radio waves are designed to be too short to travel along the arc of the Earth's surface.Therefore, it can only be used for aircraft at a certain height above the horizon and at a distance of about 25,000 feet high and a distance of 200 miles.This greatly limits the area we can attack.Still need to find some better way. Since 1941, when this idea had been proven to be practical, Professor Lindemann had demonstrated that by installing a radar device on an aircraft, a map of the aircraft's flight over the ground could be projected on the cockpit display. on the light curtain.If the bomber navigates by means of the forward method or other methods, when it is about fifty miles away from the target, the switch of this radar can be turned on, and the bomb can be dropped in the cloud without interference and error.Distance is no longer an issue.Because, no matter where the aircraft goes, it carries radar eyes, and the radar eyes can see the ground in the dark.

This method, which was later known by the code name hydrogen sulfide, encountered many twists and turns. During a considerable period of time, I was warned from time to time that there was no hope of success.However, as shown in the memo below.I insisted on urging this development topic, and finally succeeded.A special ultrashort wave is used.The shorter the wave, the clearer the image on the screen on the plane.The waves were called microwaves, and the machines for sending them were an entirely British invention, a great innovation in radio warfare both at sea and on land.They couldn't copy it until it fell into German hands.But that's all for later.At this critical juncture, apart from engaging in scientific research, there is no time to take care of others.The first step is to make a model that can actually be operated.If it works, we'll have to mass produce it, put it on the plane, and teach our crews how to use it.If too much time is spent on experimentation, the production will inevitably be delayed, and accurate bombing will not be possible for a long time.

Prime Minister to Air Secretary April 14, 1942 We have great hopes in our bombing campaign against Germany for the next millennium winter; we should do everything in our power to match the enormous manpower that is being devoted to this purpose throughout the country.It was the duty of the Air Ministry to ensure, with the aircraft at their disposal, that the best bombs were dropped on the German cities in the greatest quantity.Unless we can be assured that the majority of the bombs we drop will actually inflict some losses on the enemy, it will be difficult to justify our superiority in this form of attack.The following items appear to be necessary for success:

(1) Make sure the aircrews practice the use of blind bombing devices; by the autumn most of our night bombers will be equipped with such devices. (2) Find out the navigator's difficulties in using the sextant when using star navigation, overcome these difficulties, and ensure that they can use this method to fly close to the target within twelve to fifteen miles. After that, the blind bombing device will be It works. (3) Make sure that the mass of bombers we expect is not prevented by bad weather.This requires the preparation of a suitable runway at the airport, a device to guide the landing of the returning aircraft, and a possible anti-fog device; in the aircraft, install an ice-melting device and a blind bombing device, etc.

(4) Be sure to have a certain number of incendiary bombs and high-charge bombs on hand, even if the penetrating power is weak.I mentioned this last July and was assured that there would be no shortage.But, I think, the thousand-pound and five-hundred-pound bombs we have stockpiled in bulk are still of the old, useless type. We should expect that the enemy will also improve his defense methods on the ground and in the air.As far as I know, many devices for countering the enemy are already in place, and we are doing our best to support them during this period.No doubt you will learn that all things work together.In this way, when necessary, we can install and use these devices in time. Three weeks later, I called a meeting and approved an emergency plan. Prime Minister to Air Secretary May 6, 1942 It is reported that many of the matters I mentioned in the memorandum of April 14 have been dealt with, and I am very happy about this. I hope that a large order for hydrogen sulphide has been arranged and that nothing should be allowed to prevent this instrument from being completed on time.If we can get our way, our battle situation next winter will be greatly improved. Your report mentions that it is surprising that the Aircraft Production Department will not be able to supply all the medium-explosive bombs before the end of the year.I wrote to you on this point last July, and your reply was that they had promised to supply as soon as possible.Now it looks like they're still waiting for the hammer test and all that.Certainly, it is much better to throw a large number of high-explosive bombs with thin walls than to waste our bombing power in such a large amount. While all major issues are being addressed, there are many areas that must be completed in due time, so it is best to assign someone responsible, take necessary actions on due dates, and report monthly.I have heard that Sir Robert Renwick was a man of courage and experience, who had made a great contribution to the advancement of the device.Maybe you'll think he's the right guy.It would be the greatest misfortune if we found out later that the bombing program had been hampered by a failure to complete a certain task. There was some anxiety at the factory, but, by the 7th of June, I was able to write the following letter: Prime Minister to Air Secretary June 7, 1942 Very pleased to hear that the initial tests with hydrogen sulphide have been very successful.However, the slow pace of the production schedule makes me very anxious.Three sets were produced in August and twelve in December, and that doesn't even get the initial fix.Although we cannot yet equip all our bombers with such a device, we must do everything possible to achieve a sufficient number so that our bombers will be able to see their targets by the autumn, so that nothing should hinder this device production. I propose a meeting next week to discuss this and see what else can be done.The results of our second major air raid were rather disappointing, and the production of this device was therefore all the more urgent. I am delighted that you have arranged with the Secretary of State for Aircraft Production to invite Sir Robert Renwick to take part in the expedited production of the radio equipment required. However, I hope you will not distract him with too many scattered instruments.The main problem is hitting the target, and we can do that with hydrogen sulfide.Of course, all other items are useful, but unlike this device the need is urgent. What is urgently needed is the parallelism of training, airfields, runways and bombs, and it is for this reason that I recommend that Sir Robert Renwick be best placed to take charge of the overall work.The difficulty of coordinating all this is obvious, but the urgency of the need is even more unmistakable.If you do not wish to have Sir Robert Renwick in the position, I entrust you with selecting someone else who will be responsible for keeping all relevant matters in line, lest we end up discovering an item that has been neglected.It seems to me that the normal procedure for this to be done by the Air Ministry is greatly inadequate. As for the bomb, you told me in your memorandum dated July 19, 1941, that you had placed a production order for a 500-pound special bomb while you were working on a design for a larger bomb .You have stated in several meetings that you fully concede that the bombs are superior to ordinary bombs; however, I am disappointed that we have to expend so much effort to load bombs which are half as explosive as they should be. Hydrogen sulphide was so important to our bomber operations that the Secretary of the Air Force took care of the matter himself. Prime Minister to Air Secretary June 15, 1942 It is very kind of you to preside over this work yourself.Do keep in touch with Lord Cherwell so he can keep you informed of my views. I would like to have a meeting on hydrogen sulphide on Wednesday at 11 am. As early as 1943, this device could be used in combat.Therefore, it was issued to the navigation crew, which was compiled a few months ago after the German 100th combat group.Receive immediate results.Its use is not limited to ground bombing either.For quite some time, our aircraft have carried radar for aerial use to detect surface ships at sea.This is called an air-to-sea surface search radar.However, by the autumn of 1942, the Germans began installing special receivers in their submarines in order to detect the signals from such instruments.Therefore, German ships can dive to the bottom of the sea to avoid attack.As a result, the number of enemy submarines sunk by our Air Force and Coastal Defense Corps has decreased, while the number of losses of our merchant ships has increased.It is very effective to replace the air-to-sea search radar with fluidized hydrogen.In 1943, hydrogen sulfide played a role in the eventual defeat of enemy submarines.But before it could be made, I had to ask President Roosevelt for help, and he kindly helped. former navy personnel to president roosevelt November 20, 1942 1. One of the most effective weapons for chasing down enemy submarines and protecting our transport fleet is the long-distance aircraft equipped with air-to-sea search radar equipment. 2. German submarines have recently been equipped with an instrument that enables them to listen to the waves of our air-to-sea surface search radar equipment with a wavelength of one and a half meters.Therefore, dive safely to the bottom of the sea before our aircraft reaches the scene.As a result, our daytime patrols in the Bay of Biscay were largely ineffective in bad weather, and our nighttime patrols with searchlights were almost entirely ineffective.As a result, the number of enemy submarines spotted dropped sharply, from one hundred and twenty in September to fifty-seven in October.Before the aircraft is equipped with a centimeter air-to-sea surface search radar that the enemy cannot receive radio waves at present, it is difficult to expect an improvement in this situation. 3. One of the main purposes of patrolling the Bay of Biscay is to attack submarines traveling to and from the Atlantic waters of the United States.Now, the waters are doubly important because many American convoys pass through the vicinity of the Bay of Biscay. 4. Modify our Wellington aircraft and install a centimeter-type air-to-sea surface search radar made for our heavy bomber as a target detection device, so that we can control the central waters of the Bay of Biscay. 5. In the outer waters of the Bay of Biscay, the situation is even more difficult.Long-range aircraft equipped with centimeter air-to-sea surface search radars must be used. 6. Due to the severity of the sinking of ships in the mid-Atlantic, we had to modify our Liberator aircraft for use in these waters.This left us with no aircraft of adequate range to deal with the outlying waters of the Bay of Biscay, except from the limited bomber fleet dedicated to bombing Germany.Even if a batch of aircraft can be dispatched, it will take quite a long time to change and install the necessary devices. 7. I am extremely reluctant to reduce the weight of the bombs we can drop on Germany, because I think it is of the utmost importance to maintain and intensify the offensive against Germany to the best of our ability during the winter months.Therefore, Mr. President, I would like to request that you consider the immediate allocation of approximately thirty Liberator aircraft equipped with the CM Air-to-Sea Surface Exploration Radar from supplies.As far as I know, these supplies are readily available in the United States.These aircraft will be used immediately in areas that directly contribute to U.S. combat operations. In this area, our problem is not just the detection of submarines.The Germans had established two long-distance directional stations so that their planes and submarines could penetrate deep into the Bay of Biscay and the western entrance.One is in Brest and the other is in northwestern Spain.Our ambassador in Madrid heard the news about the Spanish radio station, but instead of getting Spain to seize the station which would involve us in endless legal and diplomatic disputes, it was on the advice of Dr. R. V. Jones [1] , it's up to us to take advantage of it.Through photography of this equipment, we were able to know its usage.Henceforth our planes and ships of war have been skilfully equipped with a first-rate orientation device shared with the enemy.Our Air Force Coast Defense Corps actually uses this device more widely than the Germans, and it is so effective that we have several similar directional stations in Australia and the Pacific. [1] This is Dr. Jones mentioned on page 339 of Volume II. Tell the story ahead of time!Our air offensive started well in 1943, and the accuracy of Oppo's raids terrified the Germans.News reached Hitler at his headquarters in Russia that our side had hit several factories in the Ruhr area on a cloudy night.He immediately sent for Goering and General Martini, the Luftwaffe signal director.After yelling at them, he said it was a disgrace that the British were capable of this and the Germans were incapable of it.Martini replied that not only could the Germans do it, but they had already done it during the Blitz with the aid of the X and Y launch systems.The head of state said that he does not believe in empty words, but depends on actual actions.It took a lot of effort to arrange the steps to be taken.At the same time, our Bomber Command, under the guidance of Oppo, caused great losses to the Ruhr area. However, we still have to deal with enemy night fighters.About three-quarters of our total bomber losses were caused by these aircraft.The range of activities of each German fighter is limited to a narrow airspace and is controlled by its own ground station.These terrestrial stations originally formed a long line across Europe, called the Kamhuber Line in honor of the original German general who founded it.As we try to cross or flank this line, the enemy lengthens and deepens it.From Berlin to Ostend in the west, Skagerrak in the north, and Marseilles in the south, there are about 750 such stations, spreading like ivy across Europe.We only found six, but there are too many to destroy. If they were to continue to operate, our bombers would need to pass the night fighter sentry line stretching hundreds of miles from the North Sea to the target area.Although the losses over each sentry post may not be great, they will never be without losses; moreover, sooner or later our bomber offensive will be affected.There is a great need for a simple and thorough method of disrupting the enemy's entire system. As early as 1937, Professor Lindemann asked me to make a simple proposal to the Air Defense Research Committee.The suggestion was to scatter tinfoil or other conductive pieces in the air, cut to size so that the bomber would appear false on the enemy radar screen.If our planes sprinkled the sky with a cloud of foil, enemy fighters would not be able to tell which were our bombers and which were our foils.This method came to be known as windows.Experts were somewhat skeptical, and this method was not tested until four years later; in 1942, at the instigation of Professor Lindemann, a test was held in absolute secrecy.These trials were conducted by Dr. Jackson.One of our leading spectroscopists, he joined the Air Force early in the war and was noted for being an excellent night fighter pilot.After the test was successful, the window method was developed rapidly.At first glance, it seems that these false targets should be the same size as the aircraft in order to produce a clear response.But if the foil is cut to the right size for the enemy's radar response, it doesn't have to be as big as an airplane, and, because of the modest size, the response is far better than a bunch of incongruous metals like an airplane Stronger. After some encouragement from the superiors, a simple and ingenious method was finally developed in 1942 to manufacture this kind of foil, which is called harmonious bipolar in the technical profession.It was found that a metal-coated strip with only one side, like the usual chocolate wrappers, was sufficiently strong to reflect radio waves if cut to size.Scattering several handfuls of these paper strips weighing no more than a few pounds from an aircraft, flying and falling like a cloud, spreading all over the digital space, can make the radar produce almost the same as that produced by an ordinary bomber. reaction.If many bombers swarmed the sky with clumps of this kind of paper, it would produce false radio responses that would make it difficult for the enemy to distinguish real aircraft responses, and we hoped that this might interfere with German radars.Since the notes just blow away with the wind, in theory an airplane traveling at hundreds of miles per hour would react differently than the notes.However, it is difficult to distinguish within a few minutes, so we hope that it will hinder, if not prevent, the aiming of anti-aircraft artillery units, and it will also make it difficult for the German ground control radar operators to guide the defending fighters to find Attacking bombers. Our Bomber Command overheard this news and wanted to use it immediately to save their aircraft.However, there are obviously concerns.This method is so simple and effective that the enemy may imitate it and use it against us.If the enemy starts bombing us again as it did in 1940, our fighter jets will be equally helpless, and our own defense system will also be ineffective.Therefore, Fighter Command advocates, at all costs, secrecy until we find a way to defend against it.Afterwards, a heated debate ensued. On June 22, 1943, I called a staff meeting of the heads of Bomber Command and Fighter Command to decide on the use of windows in bombing operations.We guess that the Germans must have also thought of this method, but even if they also adopt this method, because of the weakening of their bomber power and the strengthening of our air strikes against Germany, it will still give us an advantage.Our experts are convinced that the large-scale application of this method will reduce our bomber losses by more than one-third.Therefore, we decided at this meeting that the window can be used as soon as it is not imitated by Germany and will adversely affect our situation in Sicily.Therefore, the research, manufacture, installation, etc. of the defense measures that should be taken in our country are given extremely priority. Dr. Jackson played a leading role in actively pursuing and promoting this work.The windows were first tried out during the air raid on Hamburg on July 24, 1943, and the effect was greater than expected.The confusion caused by this approach can be seen in the heated arguments we intercepted between German ground controllers and fighter pilots.In a considerable period of time, the losses of our bombers were almost reduced by about half.To the end of the war, despite the quadrupling of German fighters, our bomber losses never exceeded those before the windows were introduced.The advantage gained due to the use of windows was reinforced by a series of other radio defense measures and tactics. There was and is some debate about whether we should use windows as early as possible.It is difficult to give a straightforward answer because of the many factors that must be taken into account.No one can say with certainty how formidable the German bomber force was in the summer of 1943.If the enemy launches another air attack on us and our defense facilities are not as good as they were three years ago, our people will suffer.All in all, it can be said that we are using this approach at the right time.We learned after the war that a German technician had made a similar suggestion.Goering immediately understood the dangers of this approach to defense.Therefore, all documents related to this matter were immediately sealed up, and it was strictly forbidden to talk about this matter.Before we began to use this method, they were afraid to use it for the same reason that made us so long hesitate.The Germans finally used this method during the winter and spring of 1943-1944, but by then their bombing capabilities were exhausted and they were pinning their hopes on rockets and unmanned vehicles on the plane. All of this will be described in due course.We have seriously disrupted the system of chronology.