Varhaug, Sonne and Elektra E-Book

John Harris

• Herausgeber: Uniform
• Kategorie: Sachliteratur, Reportagen, Biografien
• Sprache: Englisch
• Veröffentlichungsjahr: 2024

Seitenzahl: 186

Beschreibung

May 11th 1941 - Berchtesgaden. The day after Rudolf Hess took off from Augsburg and hadn't yet returned or sent any signal, Adolf Hitler had to say something to justify Hess' so far unexplained disappearance. Not least for the benefit of the German nation and his then trading ally, Soviet Russia. Consequently he authorised a statement saying that Hess was suffering from a mental derangement and had succeeded in obtaining an aeroplane against the strict orders of the Fuhrer. Of course, nothing could be further from the truth, but an explanation had at least been proffered before British propaganda commenced. The unlikely explanation has however proven durable, some still believing it to be true 80 years later. In this, their eighth book on the affair, Harris and Wilbourn demonstrate that far from being a random act, the flight had been meticulously planned, using state of the art German radio technology. Using contemporary equipment, maps and charts they demonstrate the true nature and character of the flight and explain what went wrong, leading to the sensational and very public arrival of Rudolf Hess in Scotland at 23.09hrs on May 10th 1941.

Leseprobe

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VARHAUG, SONNE AND ELEKTRA

JOHN HARRIS AND RICHARD WILBOURN

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Contents

Title PageAcknowledgementsIntroductionChapter 1The Technology: Aerial Navigation and the Harsh TruthChapter 2Solution Number One: The Siemens K4ü: Autopilot: The Ability to Fly on a Fixed Compass BearingChapter 3The Lorenz Company and the Evolution of Elektra, Sonne and ConsolChapter 4The Planning – ConventionalChapter 5The Available EvidenceChapter 6The Discovery of the Gnomonic ChartChapter 7The Point of No Return (PONR) and It All Begins to Make SenseChapter 8So What Went Wrong? And ConclusionsBibliographyAlso published by UnicornCopyright

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Acknowledgements

As per usual we have relied on the many others who know far more than we do about a given subject. We have collated and edited the information and evidence for the purpose of telling the 1941 Hess flight story.

In particular this time we would like to sincerely thank:

‘Funksammler’ of Normandy, France, for allowing us to reproduce his treatise on the Siemens K4ü. Do please visit his website, which is excellent: www.funksammlermilitaria.com.

Arthur Bauer of Diemen, the Netherlands, for allowing us to reproduce his treatise on Elektra Sonne/Elektra Sonnen. Again, do please visit the associated wonderful website: Stgcdv&[email protected]. Arthur is the acknowledged expert in all matters of German navigation, and we are truly honoured that he has allowed us to use his work in this manner. He has recently opened his collection to the public, and we look forward to making the trip to Holland.

Dr Phillip Judkins of the University of Cambridge for his knowledge, liaison and help with establishing further contacts. Dr Judkins is also the chairman of the Defence Electronics History Society (DEHS).

Nick Gilder of the RAF Signals Museum, Henlow for support and assistance. It is to be hoped that an appropriate repository for the collection of military radio equipment can be found subsequent to re-development of the site.

Andrew Rosthorn and Spike Hodbod for their continued support over what is now a very long period of time. vii

Dieter Beikirch of the Deutsche Avionic Sammlung, Minden, Germany. Dieter has been very helpful in providing rare diagrams of the FuG 10 EL remote-control apparatus as described in the 1989 Helmut Kaden Munich lecture.

The staff of the British Library, St Pancras, London for thankfully locating their long-lost Sonne chart. This chart proved to us that we were correct in our assertion that Hess was using the state-of-the-art Luftwaffe radio navigation system. It also proved (to us at least) that Hess was not acting alone. This is not a simple technology.

Helen and Annie Cara for file management.

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Introduction

On 12 February 1950, Rudolf Hess was incarcerated and languishing in the old Prussian prison, situated in Spandau, Berlin. When not planning the finer details of a new Fourth Reich, he dutifully chose to write home to his wife Ilse, who was then living in the Allgaü, southern Germany. They had not seen each other since the lunchtime of 10 May 1941. After the usual pleasantries the former Deputy Führer chose to describe, for some reason, certain aspects of his sensational flight to Scotland, which, by then, was some nine years earlier.1

The reader may recall that at the time (in 1941) the said flight was described by the German news department as the act of a delusional madman who had stolen an aircraft and flown to the enemy. Hess and his entourage were effectively disowned in public and various associates arrested (though later quietly released). After the war had ended, the 1945–6 Nuremberg trials had provided no further clarification as to either motive or methodology of the flight, and so the content of this much later letter was to prove significant, especially as it was also allowed to be published in book form in 1954.2 It was the first time that any form of first-hand explanation would be available subsequent to the nonsensical, but with hindsight, quite understandable, 1941 communiqué. (Adolf Hitler wished to distance himself from the flight that had just gone disastrously wrong and consequently had to keep Stalin guessing as to what had really happened. Barbarossa was then just over a month away.)

However, rather than describe the theft of the Bf 110 and how he had fortuitously managed to get as far as Scotland, instead the ixformer Deputy Führer complained to his wife as to how his radio navigational system had let him down at the ‘decisive moment’. This was surely the beginning of a very different story – one that we have spent the past thirty-five years trying to understand and research. This book details our findings and explains precisely how Rudolf Hess managed to fly one of the world’s then fastest planes from Augsburg in Bavaria to Floors Farm, Eaglesham, just to the south of Glasgow in Scotland.

Delusional he certainly was not, nor was the plane stolen …x

Notes

1 Ilse Hess, Prisoner of Peace (Germany, 1954)

2 Ibid.

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Chapter 1

The Technology: Aerial Navigation and the Harsh Truth

Aerial navigation has never been easy. Were it so this book would not have been necessary, as in May 1941 the Deputy Führer of Germany would no doubt have made his way without incident to RAF Dundonald in Ayrshire, Scotland, and the course of world history from that point forward may well have been very different. However, just how difficult accurate wartime aerial navigation remained in 1941 was amply illustrated by David Bensusan-Butt (1914–1994) who was commissioned by his employer, Frederick Lindemann, 1st Viscount Cherwell,3 to write a report on the effectiveness of the early British bombing raids over Germany. Butt, a peacetime economist and statistician, duly reported the damning conclusion that only 5 per cent of all Allied bombs were dropped within 5 miles of their target. This report was issued in August 1941, only three months after the Hess flight, and clearly demonstrates the difficulty of precise wartime aerial navigation – all factors considered.4

In wartime there are obviously more factors and diversions to consider than simply navigation – anti-aircraft fire and enemy fighters to name but two very persuasive ones. There are various reasons as to why a target may not be reached.

Admittedly, up to 1941, Britain had been more concerned about defence than attack for obvious reasons, but at this early stage of the Second World War, and as a direct reflection of the war to date, Britain and the Allies were certainly well ahead of the Germans in terms of defensive radar capability. The Chain Home system and 2its synergy with the Royal Observer Corps had proven its efficiency and worth throughout the long hot summer of 1940. Conversely, the Germans were certainly well ahead in terms of radio navigation on account of their perceived and apparent need to bomb British cities accurately. Two very differing needs and priorities, but as the old saying goes, ‘necessity is the mother of invention’.

So, let’s briefly look at the development of air navigation up to the start of 1941, and then look at the precise technology that was available to Rudolf Hess when planning his flight.

The first Zeppelin took to the skies in July 1900 and the Wright brothers precariously took to the air three years later in December 1903. Prior to those dates navigation was very much the preserve of the naval navigators (and perhaps a few very intrepid balloonists), but many of the fundamental issues that have to be at least appreciated are common to both disciplines. By way of illustration, we have acquired a 1942 copy of Teach Yourself Air Navigation.5 While not specifically aimed at helping flights such as those of the Deputy Führer’s a year before its publication, it does indeed illustrate the basic problems that all air navigators have to face, war or peace notwithstanding. We should say that the book was aimed very much at the Air Training Corps’ (ATC) candidate and so does not even contemplate what radio navigational methods were then available. That particular technology remained very much top secret in 1942, on both sides of the English Channel, and so the finer details were certainly not available to the typical British ATC student trying to pass their introductory exams. They would quite properly have to learn navigation the hard way from the basics.

The chapters in TeachYourselfAirNavigationare as follows:

Direction and Distance on the earth’s surfaceMap projections 3Variation of magnetic compassesDeviation of the compassThe effect of wind on an aircraftMap readingFixing and reporting positionAircraft magnetic compassesElementary meteorologyAir speed indicators and calibrationGround flight

Figure 1.1. The 1942 ‘Teach yourself Air navigation’ 4

We hope the reader can see the relevance of the above in the context of the Hess flight. Rudolf Hess had learned how to fly at the very end of the First World War in Bavaria, though had never actually experienced deadly aerial combat. However, he would have been taught the basics (just like the much later ATC student), such as those listed above and, indeed, the flight map that he brought with him in 1941 (and now resides at Lennoxlove House, Haddington) was commented upon as ‘being marked in accordance with the practices of the last war’.6 While we do not wholly subscribe to this viewpoint it is certainly the case that the major physical landmarks, visible from the air, such as railways and hilltops, were indeed meticulously marked up.

This comes as no surprise and many of the later advancements in navigation were no more than Hess’s and man’s attempts at mechanical and electrical solutions to some of the above issues. Modern-day Global Positioning System (GPS) is of course a continuation of the process. Hess was certainly no fool and realised that in planning the substantial journey from Bavaria to Scotland he would have to be mindful of all the above factors. However, and in particular, he could no longer rely on purely visual recognition, typically his and the main First World War technique, as he would now have to fly a long leg up the North Sea, where, of course, there were no unique visual markers. He also needed to avoid, as best he could, the other key anti-aircraft measures, such as the British RAF Coastal Command and the fledgling Home Chain radar system (though it is possible that he was not even aware of its existence – the Luftwaffe had earlier discounted the Chain Home Low towers as mere radio towers). That is where his life would start to get especially tricky. Planning would be key.

It is the planning aspect of the flight that this book concentrates on, clearly demonstrating that the flight was certainly not the act of a madman. It is our contention that Hess had meticulously planned 5his flight, but despite the planning (or some might say because of its radio navigational aspects) it went dramatically wrong. His eventual recovery from a near catastrophic event certainly shows that Hess was not delusional. In fact, this recovery was just as impressive as the initial planning and his attempted use of the then cutting-edge technology.

Notes

3 Viscount Cherwell was the British government’s leading scientific advisor during the Second World War

4 The Butt Report – Air 14/1218

5 ‘Kaspar’, Teach Yourself Air Navigation (London, 1942)

6 Letter, R.H. Melville to the Duke of Hamilton, 22 May 1941. On display at Lennoxlove House.

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Chapter2

Solution Number One: The Siemens K4ü: Autopilot: The Ability to Fly on a Fixed Compass Bearing

The increasingly battered eighty-one-year-old fuselage of BF110 – VJ+OQ currently resides at the Imperial War Museum (IWM) Duxford in Cambridge, in the AirSpace hangar. (Turn left when exiting the ticketing hall.) It has been passed from pillar to post since its arrival from IWM Bedlam in London in 2012, and we are far from sure if the present curators understand the true significance of the absolute jewel that they are the custodians of. If they did it most likely would be in the British Museum (or, cynically, more likely be hidden away, its existence completely secreted) – not consigned to an inconspicuous corridor in a Cambridgeshire museum, complete with full public access.

Of particular note is, first, there is no auxiliary oil tank supply (being clearly tapped off by way of a substantial brass nut), which simply means that Hess could not have flown from Bavaria to Scotland – his engines would have been starved of oil (not fuel) and would most likely have seized somewhere over the North Sea. This revelation, which has been the subject of our previous books, has already been well covered and the implications explored and explained. It would be very unlikely indeed that a sensible Bf 110 pilot, anticipating such a long flight, would simply leave to chance that he would have enough oil to complete the journey. This could in extremis effectively amount to suicide. An auxiliary oil tank, or an en route landing, would be the only options, and we know for sure there was no auxiliary oil tank fitted. Please check the details for yourself.77

Secondly, and as far as we can ascertain, there are the major remnants of a Siemens K4ü in the forward section of the fuselage, though again badly damaged, demonstrating that Hess had the ability to fly on a set bearing. However, it is important to note that the machinery would not automatically fully adjust for the effect of wind drift. This problem has bedevilled the navigator since flight began, and most early aviators used ‘dead reckoning’ as the usual method of accounting for (or trying to account for) the effect of wind on a particular course. The method was and is always fraught, especially if trying to plan over a long distance, which is of course exactly what Hess was attempting to do, the main weakness being that wind drift had to be estimated from weather charts prior to the outset. In 1941, there were some rudimentary mechanical wind sights that allowed in-flight readings to be taken, but these were dependent upon the navigator literally protruding a telescopic device from the side of the aircraft mid-flight, and we have certainly seen no evidence that Hess had such machinery, or more pertinently the time or inclination to take such readings. He already had to contend with enough problems …

Figure 2.1. The remnants of the Siemens K4ü that still resides in the Bf 110 fuselage at IWM Duxford. 8

The Siemens’ system relied on a sophisticated autogyro compass, one that was mounted in the central fuselage of the Bf 110. It is noticeable and relevant that the immediate pictures of the Hess fuselage in Eaglesham, post-crash, show the fuselage intact and no inspection plates removed. However, once taken to Carluke, the local RAF scrap yard, the inspection plate detailing the gyrocompass has clearly been removed. We show the progress by way of pictures to demonstrate the point.

We now know, thanks to Andrew Rosthorn, that Royal Aircraft Establishment (RAE) Farnborough had indeed sent one David Mitchell from Carluke to salvage the Bf 110 and the compass was most likely removed as part of this process.8 Thereafter the fuselage inspection panel is always shown as being removed. The compass was linked to the damper (see Figure 2.21), which then mechanically adjusted the rear rudders for the effect of drift and movement.

Figure 2.2. One of the first images of the crashed plane. Note the intact inspection hatch on the top right of the Balkenkreuz.

Figure 2.3. A second picture at Carluke also showing the still intact inspection hatch. 9

Figure 2.4. The location of the master compass and access hatch within the fuselage of the Bf110.

Figure 2.5. The plane on the Queen Mary trailer, in late May 1941, clearly showing the hole where the inspection hatch was later removed presumably by David Mitchell on behalf of RAE Farnborough. 10

Figure 2.6. The fuselage as can be seen at Duxford. (The wrapping plastic has also now been removed.

We hope the reader can now understand our pleasure at finding part of the early ‘auto-pilot’ in situ in the fuselage of the Hess plane, as clearly its use potentially eliminates all the problems of flying in a straight line while going up the North Sea. What is needed is to understand and learn how the device worked. In this connection we consider ourselves very fortunate to have been given permission to reproduce an excellent treatise on the operation of the Siemens’ device, written by a true expert in its operation (who has a fully working example at his Normandy home). So, over to you, ‘Funksammler’ (‘The radio collector’).

General

One of the most widely used Kurssteuerungen used by the Luftwaffe was the K4ü system built by Siemens (Luftfahrt Geraete Werke Hakenfelde).

Siemens started the development of their K4 system from about 1936. The Luftwaffe required the system to be 11compatible with the Patin remote compass system. Together with some other lessons learned in early applications of the K4, this led to the development of the K4ü (the ü standing for ‘überarbeitet’, which means ‘revised’). More than 50,000 examples of this autopilot were built from about 1938 to 1945 and were used in aircraft like the Messerschmitt Bf 110, Junkers Ju 88 and Heinkel He 111.

​Description of the K4ü autopilot

Figure 2.7. Overview of the K4ü installation.

Apart from the aforementioned Patin master and daughter compass, the K4ü consists of

an LKu 4 Kurskreisel directional gyroscopean LKz 3 Kurszieger indicatoran Lrg 9 Richtungsgeber course adjustment switchan LKMm Kursmotor course adjustment motoran LRM 4ü Rudermaschine servo unitan LSch 4ü Hauptschalter main switchan Stützschalter compass coupling switchan LKW 121⁄4ü Wiederstandskasten resistor boxan LKW 3 Wiederstandskasten resistor boxan Notauslöseknopf emergency release knob.

A number of variations of the K4ü system could be supplied, denoted by a number behind the name, for example K4ü-1 or K4ü-7. These versions differed mainly in the number and configuration of the control switches, so that the system could be tailored to different types of aircraft. For example, an additional Lrg 5 or Lrg 10 direction switch could be placed at the bomb aimer’s position. With a special extension this switch could even be coupled to the Lotfe bombsight so that aircraft could be adjusted during the bomb run. For twin engine aircraft an LDS 10-2/4 Einmotorenflugschalter or single engine flight switch could be added, which automatically changed the balance of the autopilot to deal with the drag of a feathered propeller. Additional resistor boxes would be needed to tie these various optional switches into the K4ü autopilot.

​The Functioning of the K4ü autopilot

Theprinciplesoftheautopilot

To understand the functioning of the autopilot, a little bit of control theory must be understood.

First, there needs to be a stable set point, a set course that the aircraft needs to fly towards. If the aircraft deviates to the left of the set course, the system needs to steer the aircraft back to the right, and vice versa.

The force generated by the measuring system is far too small to operate the rudder of the aircraft directly, so the second requirement is a large power amplification. As there is a time delay between the disturbance of the set course and 13the action of the rudder, this system tends to oscillate unless stabilised or ‘dampened’. On slower aircraft the aerodynamics of the aircraft itself have a stabilising effect, but as aircraft got faster and ‘slippier’ another means of damping these oscillations was required.

Figure 2.8. Functional overview of the K4ü autopilot.

So thirdly a ‘damping gyroscope’ or ‘Dämpfungskreisel’ is required. This gyroscope measures the angular velocity of the aircraft. If this angular velocity signal is added to the course deviation signal a ‘proportional, derivative’ control system is created, which was proven to be effective in early war aircraft with a relatively low natural resonance frequency. 14

Figure 2.9. Principal working of the autopilot. Note the four stages of a disturbance indicated on the left of the drawing and which parts of the autopilot engage in countering the disturbance.

​The Patin Führertochterkompass and the Kurskreisel

Figure 2.10. The principal instrument cluster used with the K4ü autopilot. Left top: the Kurszeiger placed above the Fuhrertochterkompass. Top right: the indicator that the bomb aimer has taken control over the Kurskreisel.

The first task was to provide a stable set point or course. Since the magnetic Patin compass system is not stable enough to provide a signal directly to the autopilot, an LKu 4 Kurskreisel directional gyroscope is used to stabilise the course heading.

A directional gyroscope is typically accurate in the short term, but due to internal friction and even the rotation of 15Earth it will slowly drift out of kilter. The solution was to use the magnetic Patin compass to influence the set point of the directional gyro.

A special repeater compass, the Patin Führertochterkompass PFK/f3, was fitted with an output resistor, which provides a positive or negative output voltage dependent on a deviation to the left or right. This output resistor only works within +/- 30 degrees of the set point and, for this reason, all Patin repeaters have markings to indicate +/- 30 degrees from the set point. The output voltage of the Patin repeater adjusts the Kurskreisel readout at about 1 degree per minute. Because the swinging of the magnetic compass is much faster, the effect is that Kurskreisel integrates or averages the magnetic course.

Figure 2.11. A Patin PKT/f3 Führertochterkompass. Note that this version has two plug sockets on each side of the instrument.

The actual set point of the Kurskreisel and the Patin repeater is adjusted with the Kursmotor, an electric motor that is connected via shafts and gears to the back of the Kurskreisel and the Patin repeater. The top scale of the Kurskreisel shows the set course, which is synchronised with the course at the 12 o’clock position of the Patin repeater. If the aircraft is heading exactly towards the set point, the bottom scale of 16the Kurskreisel corresponds to the top scale, and the aircraft symbol on the Patin repeater points at 12 o’clock.