Could proximity fuses have halted the bomber offensive against Germany in 1944? (1 Viewer)

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if you are still puzzled and until a ballistics expert appears you might try the high school physics i used to check this. Starting 6 or 7metres call it 20ft short of the middle of the target calculate how far any fragment travelling at 2200 ft per second radially would get before impact (2200 was a figure i got from online source so a low credibility but it 'sounds right'). Result is about 40 or 50ft right? The area goes up by the square of the distance from target. And that is a 100% swept area as far as the aircraft skin is concerned until the pattern of fragments loses cohesion. Because the fragments take some time to acceelerate to 2200 ftpsec the real radius would be much less - as far as i can tell the 'delayed fragment' diameter of effect would be about - 88 to 100mm for a 88mm shell. Thats why 70 ft distance of detonation is much better than 6 meters or 7 metres

Something seems more than a bit off here. Or I am not understanding the situation. The Fragments spend about zero time/distance accelerating. They are moving about as fast as they will ever go within a few inches of the shell bursting. Fragments have really crappy ballistic shape, they make round balls look good and they slow down fairly quickly, a lot depends on size which is why so much work was put into optimizing fragmentation, matching explosive to shell body material/alloy and heat treatment. Too many small fragments and the lethal destiny of the "cloud" thins out pretty quick and lethal range is short. Too many big fragments (a sort of contradiction in terms, large size fragments means you won't have a large number of them) and the big fragments are dangerous to large distances but with few fragments the chances of a hit go down. The 2200fps figure may have been an average or average speed at a given distance.
Most extreme example is the old cast iron Pineapple grenades which, if filled with HE never split up along those grooves. They split up into 3-5 large chunks and a lot of cast iron dust/powder and while the large chunks were dangerous at over 100yds at times the dust was pretty ineffective at just a few yds.
Now a 70ft "miss" distance is way too far away to be effective. Please do the math. 70ft radius means a 219.8 circumference. even if you can get the large majority of fragments to stay within 10ft forward and aft of the center of the shell in a horizontal fan that is a 20ft high area and thus your fragments are going into 4396 sq ft area, At 70 ft how big does each fragment need to be in order to penetrate the aircraft skin and do damage behind it. Just poking holes in the skin does not bring the aircraft down.

or you may want to remember the effect of 'grape shot' (smooth bore cannon stuffed with bent nails, bits of chain, fragments) in the days of wooden ships at very close quarters.

Actually what you are describing was called scattershot (or other names) Grape shot was actually a cluster of identical sized balls often wrapped in canvas that resembled a bunch of grapes. While such expedients as bent nails, bits of chain, fragments were used on occasion they were much too unpredictable to be used by professional gunners as common practice. They also could jam in the bore and burst the gun on occasion and were much rougher on the bore (greater wear) than "standard" ammunition. Brass or bronze barrels being more common than Iron. Also in an era were nails were hand forged by blacksmiths bent nails were hardly the "scrap" they are considered today.
What gunners used for real ammunition and what non-gunners (infantrymen and cavalry men) wrote about in memoirs were often very different things. The famous quote by Zachary Taylor "A little more grape Capt. Bragg" actually went more like.
" What are you firing Captain?"
"Canister sir"
"Well double it and give them Hell"
 
Website with CIOS reports:
CIOS

The very first one (pre-VE day) tangents the subject already:
CIOS-I-1
http://www.cdvandt.org/CIOS-I-1.pdf

I never saw any ALSOS-C reports.

There's a German book on German WW2 missiles, but I don't have it and cannot look up the fuzes mentioned.
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A revised edition is overdue since 2007, supposed to be published in 2016:
ISBN 978-3-7637-6120-3
 
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Germany was only still developing the proximity fuse at wars end after its development had been interrupted by a Hitler order around 1941. The proximity fuse was used with great effect by the Allies, most notably against the V1 flying bombs against which it was highly successful. The Americans were very mindful of the Germans reverse engineering proximity fuses and would at first not allow their use over enemy held territory through fear of a dud being captured. Proximity fuses were later used against ground targets with devastating effect and are generally considered to be one of the major inventions to come out of World War Two.
German anti aircraft batteries concentrated their fire into a box and relied on timed fuses which were timed to exploded at a pre-determined altitude with the hope and expectation that shell splinters would destroy the oncoming enemy aircraft. If the Germans had of had proximity fuses fitted to their anti-aircraft shells then presumably this would have made them far more effective as the fuse itself would have exploded the shell upon detecting the presence of a bomber.
Obviously the Allies had seen for themselves just how effective proximity fused shells were against the fast moving flying bombs and they would have been more than a bit concerned about the safety of their slow moving four engine bombers should the Germans had developed their own.

The fuse was developed at the Applied Physics Lab, the team was led by William Parsons. It was quite a breakthrough. The fuse was even more devastating against land targets, allowing air bursts. It was so effective, the US vacillated in using the fuse, for fear the Germans would obtain one and copy. Parson went on to be the person in the Enola Gay to arm the Bomb
 
Reading this forum is very entertaining. So many experts, each one proving the impossibility of ever building a proximity fuse. They must all have gone to public schools and attended college recently. The snowflake generation and it's knowledge level impresses me less every day.
Oh, I almost forgot, try reading Tuxedo Park. It's an actual book and it explains in some detail the work of Alfred Lee, Loomis. Or, if you're a snowflake, watch this video. It's on the web so it must be true. Now we can move on to other ridiculous opinions they learned in school.

View: https://www.youtube.com/watch?v=Kq_Uy5hGazc
 
Reading this forum is very entertaining. So many experts, each one proving the impossibility of ever building a proximity fuse. They must all have gone to public schools and attended college recently. The snowflake generation and it's knowledge level impresses me less every day.
Oh, I almost forgot, try reading Tuxedo Park. It's an actual book and it explains in some detail the work of Alfred Lee, Loomis. Or, if you're a snowflake, watch this video. It's on the web so it must be true. Now we can move on to other ridiculous opinions they learned in school.

Re-reading the thread, my impression is that only one member said that proximity fuse is impossible to build (on ww2 technology). The member that is rather far away from the 'snowflake generation'.

Granted, a 1st post can be written without saracastic remarks about the forum's members, wheter those being experts or not.
 
Proximity fuses were used in WW2 weren't they? I have read they were used against the V1 so the technology was available at the time.

from Wiki


Vannevar Bush, head of the U.S. Office of Scientific Research and Development (OSRD) during the war, credited the proximity fuze with three significant effects.[23]

  • It was important in defense from Japanese Kamikaze attacks in the Pacific. Bush estimated a sevenfold increase in the effectiveness of 5-inch antiaircraft artillery with this innovation.[24]
  • It was an important part of the radar-controlled antiaircraft batteries that finally neutralized the German V-1 attacks on England.[24]
  • It was used in Europe starting in the Battle of the Bulge where it was very effective in artillery shells fired against German infantry formations, and changed the tactics of land warfare.
At first the fuzes were only used in situations where they could not be captured by the Germans. They were used in land-based artillery in the South Pacific in 1944. Also in 1944, fuzes were allocated to the British Army's Anti-Aircraft Command, that was engaged in defending Britain against the V-1 flying bomb. As most of the British heavy anti-aircraft guns were deployed in a long, thin coastal strip, dud shells fell into the sea, safely out of reach of capture. Over the course of the German V-1 campaign, the proportion of flying bombs flying through the coastal gun belt that were destroyed rose from 17% to 74%, reaching 82% during one day. A minor problem encountered by the British was that the fuses were sensitive enough to detonate the shell if it passed too close to a seagull and a number of seagull "kills" were recorded.[25]

The Pentagon refused to allow the Allied field artillery use of the fuzes in 1944, although the United States Navy fired proximity-fuzed anti-aircraft shells during the July 1943 invasion of Sicily.[26] After General Dwight D. Eisenhower demanded he be allowed to use the fuzes, 200,000 shells with VT fuzes or (code named "POZIT"[27]) were used in the Battle of the Bulge in December 1944. They made the Allied heavy artillery far more devastating, as all the shells now exploded just before hitting the ground.[28] It decimated German divisions caught in the open. The Germans felt safe from timed fire because they thought that the bad weather would prevent accurate observation. The effectiveness of the new VT fused shells exploding in mid-air, on exposed personnel, caused a minor mutiny when German soldiers started refusing orders to move out of their bunkers during an artillery attack. U.S. General George S. Patton said that the introduction of the proximity fuze required a full revision of the tactics of land warfare.[29]
 
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From reading this
Proximity fuze - Wikipedia

The Germans did not have the technology to develop/produce proximity fuses during WW2 but that does not mean in a different scenario it could not have happened, after all the Russians stole the technology, from the same article.....

While working for a defense contractor in the mid-1940s, Soviet spy Julius Rosenberg stole a working model of an American proximity fuze and delivered it to the Soviet intelligence.[13]

 
The big problem wasn't the basic idea or even building a prototype. The BIG problem was being able to mass produce the things.

According to one story "By the end of the war, five separate manufacturers and 80 subcontractors around the country were producing 40,000 fuses day -- using the labor of 80,000 people."

For a good overview see; http://webarchive.loc.gov/all/20140704031301/http://www.history.navy.mil/faqs/faq96-1.htm

Please note that even making batteries for the smaller fuses that had decent shelf life was a problem, let alone the tubes/circuits, and other parts.
 
SF author George O Smith was involved in the development; Arthur Clarke, who was involved in the development of ILS said he thought the VT fuze was one of the toughest technology projects of the war. It was tough building the Copperhead missile with solid state electronics. Imagine building something, like the proximity fuze, to be fired out of a cannon with tubes.
 
Cover name of german proximity fuzes furing ww2

BAD, akustic developed by Graf Zeppelin Institut

ELKU (a.k.a. "PABLITZ") electro-acustic, developed between TELEFUNKEN and PABLITZ & Elektro-akustisches Institut, Namslau

FUCHS, active radar, developed by AEG Berlin, scheduled for Hs-117 and Hs-298

MARABU, replaced FUCHS, aktiv Doppler by Siemens-Halske subcontracted from Rheinmetall AG.
Developed for Hs-117, Hs-298, Rheintochter und Wasserfall SAN. Pre-series production finnished

MARDER and ISEGRIMM, electro-magnetic, developed for mine warefare by Orlich Institut, Danzig.

KAKADU, active radar by Doppler effect developed by Donauländische GmbH, Wien. Produced in order of 3,000 specimen for Hs-293

KRANICH, acustic by Ruhrstahl AG, Brackwerde. taken from developmental list late in 1944

KUGELBLITZ, aactive radar, Doppler by Patent Verwertungs Gesellschaft, Salzburg.
developed for SAM Rheintochter. Small series production

KUHGLOCKE, passiv electrostatic ("Glimmröhrenzündung") by Rhinemetall-Borsig. Only Prototypes

KUHGLÖCKCHEN, micro KUHGLOCKE for FLAK 88-128mm SPgr, series production scheduled for march 1945

MEISE, acustic by Neumann & Borm, Berlin, taken from developmental list nov. 1944.

PINSCHER, aktiv radar Doppler by Orlich Institut, Danzig. 5 Prototypes.

PISTOLE, photo-elektric, by AEG

ROULETTE, infrared by Brickmann, Gera.

STIMMGABEL, Akustic by Graf Zeppelin Institut. Developed for parachute delayed bombs to be dropped over bomber combat boxes. Testet, development cancelled.

TRICHTER, radio doppler by Blaupunkt. In series production by feb. 1945, in april 1945 in combat trials.

WASSERMAUS, photo-elektric, for C2W10 Wasserfall SAM.

WIESEL, aktive radar doppler by Orlich Institute, Danzig.

ZÜNDER-19, developed for SC-250kg GP bonbs by Rheinmetall-Borsig. started 1937, finnished 1943. Produktion to mid 1944
 
I think a lot of people forget that the Germans weren't the only people in the WW2 era that had brains. While they did have some "firsts," among other things, they were not able to produce a reliable wood glue for aircraft, centimetric radar, or a proximity fuze.
 
I have no doubt that the list provided by Delcyros is accurate as far as it goes, which is a list or programs/projects. Turning a project into reliable mass produced equipment was a major problem for most countries/air forces. The US for example had something over a dozen projects to turn the the .50 cal Browning into a 1200rpm gun ( multiple projects at multiple companies) and took something like 3 years to get any into the field.
It was not a question of getting an idea for a proximity fuse to work in the lab or even test range. It was getting it to work well over 50% of the time in service after the shell/fuse sat in storage for weeks or months in both tropical and arctic conditions. It was getting such a fuse to be producible in quantity (thousands per day) by production workers, not 30 or so day by laboratory technicians. Granted the Allies had longer shipping distances and transit times from factory to guns but dead batteries, broken tubes and even broken connections means a dud shell (or one that explodes using the self destruct mechanism).
Using a proximity fuse on a missile is several orders of magnitude easier than using one on an artillery shell. The volume constraints go away (for the most part) while the firing stresses are much reduced, much lower "G" loading on launch/firing. The much lower rate of spin has advantages and disadvantages. AN 88mm gun could fire a shell with over 18,000rpm at the muzzle.

Now perhaps the Germans did get one or more fuse designs to this level of development (ready for large scale production with acceptable shelf life and good (nobody had perfect) reliability in March of 1945. It was too late. A few dozen or even a hundred more bombers shot down in April of 1945 was not going to delay the end of the war by one day.
 
I do not disagree. What I do object, however, are the generalisations found in wikipedia that Germany did not had the technology to develop or produce proximity fuzes. After all, they developed, produced and fieldes proximity fuzed warheads in naval torpedoes and mines, as well as in bombs early in ww2. They also developed proximity fuzes in AAA shells and SAM, though to the best of my knowledge only obtained limited production still gearing up from prototype production to series production at wars end (depending on which project You look for). To the best of my knowledge, they did not field any of them, except for R&D and demonstration purposes.
With MT fuzed AAA shell the problem was that You needed to be precise to obtain a hit: in elevation, direction AND time. Not much of a problem for AAA trying to hit something at, say 4000ft but against a bomber operating at 20,000ft You are entering the remote upper ballistic trajectory curve, and pointing errors became more common with the common 88mm Flak 18/36 as it slowly approached it´s effective limit. US Surveys of Flak damage during ww2 indicated that FLAK litterally was precise. Hundreds of bombers came back where an 88mm went right through the A/C or the wings to explode outside harmlessly a distance beyond the plane. This didn´t went unnoticed in Germany, as there was a consistent upgrade environment for AAA shells.
The stop gap wasn´t yet the developmental proximity fuze, rather, it was the reliability of operation provided by installing a double fuze: MT & impact (non-delay action). This was first suggested in early 1944 with approx. 2 mio. shells manufactured 1943 & 1944 but fielding of them was initially countermandated on account of the higher danger during transportation. Only during april 1945 did the FLAK batteries around Munich received clearence to field test their stock of double fuzed AAA shells with the result that the number of bombers brought down increased fourfold for the same amount of ammunition spent.
 
The ability to make proximity fuses for torpedoes/mines is hardly an indicator of the ability to make proximity fuses for AA shells.

US Mark 6 exploder
220px-Torpedo_exploder_Mark_6_Mod_1.jpg

space in torpedo
torpedo_side_view_and_interior_mechanisms,_Torpedoes_Mark_14_and_23_Types,_OP_635,_March_24_1945.jpg

This was the infamous magnetic exploder. A form of proximity fuse. Other torpedoes and mines used different exploders using different principles but the size constraints were nowhere near as bad as an AA fuse. Described as fitting 300 components in a tube the size of two toilet paper tubes placed end to end. The under water exploders could also function much slower (speed of torpedo/mine being much slower than a AA shell) and the under water units also had nowhere near the "G" loads placed on them as the AA shell units did.

The basic "idea" of a proximity fuse is rather simple. Turning it into a laboratory functioning example is harder but doable using a number of different sensor systems. Being able to get it work in the field as a round of ammunition (take from box and shoot it vs take from box, test/trouble shoot/repair/retest and then shoot) at acceptable levels of reliability is another story. According to the following account the price of a proximity fuse fell from $742 to $18 by the end of the war.

See: Innovation During WWII

for some more information on the development of the Allied proximity fuse.
 
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I do not disagree. What I do object, however, are the generalisations found in wikipedia that Germany did not had the technology to develop or produce proximity fuzes.
I was not meaning to be derogatory just stating a fact. German technology was good but to affect the war air defense needed huge numbers of fuzed munitions in late 1943. Ammunition that explodes in transit or being handled is not a minor issue, it is solving these issues that takes the time. The allied (American) use against the V1, the Battle of the bulge and against kamikazi were very limited compared to the task of defending the whole of Europe from high altitude air attack.

There is no doubt Germany could have developed working proximity fuses and mass produced them but not in time to affect the war.
 
As above, while that is reaonable as a concept, we must be aware that the idea relies heavily on two presumptions:

A) on the historic allied choice not to use proxy fuzes over land until "the end was in view" (When they did finally, dud fuzes were recovered and studied)
B) on the case the proxy fuzes were below/above the german perception realm of their needs

As it turned out factually, there was no workable proxy AAA shell in service in Germany at wars end, so it can be deduced that both presumptions are largely, if not completely valid. However, to state that the development and production of such a design was beyond Telefunken, GEMA, Lorenz et al. capability will cause induction of a third premise:

C) even if they had recovered a sample in time, they would not have been able to reverse engeneer it due to failing in their technology.

I stand firm that this presumption is not a valid one, the allied perception appears to be directly counterfactual to such a presumption, fear of losing VT fuze technology to be reverse engeneered beeing the main factor driving a ban against the use of VT over land.

Moving away from the proxy fuze, the question remains what effect would dual fuzed AAA shells (MT and impact fuze) have in the bombing campaign, a design which indeed was produced en masse back in 1943 and was only hold back due to a personal change in the head of the FLAK organisation and a misconception on the successor´s behalf.

statistical average of AAA ammo spent per A/C kill 1945 (figures given as ca. against daylight box formation heavy bombers in high altitude):

88mm Flak 18/36: 16000 with MT fuze, 5000 with double fuze
88mm Flak 41: 8500 with MT fuze, 3000 with double fuze
105mm FLAK: 6000 with MT fuze, 2000 with double fuze
128mm FLAK: 3000 with MT fuze, ca. 50% MT with double fuze but sample size too small to be reliable

compare Gen. of the FLAK Axthelms´s post ww2 interrogation report, the numbers he cites are different to those above but yield the same figure of merit: ca. 1:3 in favour of the double fuze.

http://downloads.sturmpanzer.com/FMS/NARA_FMS_D031.pdf

best regards,
delc
 
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All true, but figures from 1945 ignore the certain fact that the allies could have stopped all bombing in January 1945 and it would have had almost no effect on the war at all.
 
The question I extract from Axthelms account is a different one than whether or not the allies would have won ww2. There is no doubt about that.
Rather than 1945, the question whether or not the allies could decide to stop daylight bombing during spring 1944 or winter 1943/44 is cast. I don´t think they would, at least not without serious ramifications elsewhere (german fuel situation would have improved very markedly for the remainder of 44 and 45). Realistically, the option of D.Z. fuzed AAA shells was articulated late 1943 and in spring 1944 again. The shell was produced in mass, too, so we do not need to resort to proximity fuzed AAA, which is a bit of a stretch historically. The impact, this shell would cause on tight bomber combat forces is a very significant factor to this discussion. Certainly, they would have done little against the many barrier fire batteries with poor firectontroll but regular FLAK batteries, and the now employed Grossbatteries protecting key targets with multiple firecontroll radars would have received a massive increase in fire effect day and night.

MT fuzed shells striking an A/C would have rendered the fuze unservicable, causing duds and low order detonations. D.Z. fuzed AAA shells would be able to explode always high order on predefined time or impact, depending on which circuit was closed first. Rate of fire very significantly improved with D.Z. shells (similar to AAA firing VT-fuzed shells enjoying this nice side effect).
 
There was a functioning German gun launched shock hardened proximity fuse. I know how it worked, it was test fired successfully in 1943 with a detection range of about 2m, and this was improved to 5m and then 10m and finally 15m. I'll be able to provide a few links and drawings when I get on something more comfortable than this iPad.

It was tested again in 1944 (about 1000 8.8cm rounds with a low dud rate fired). By then development was essentially complete. Conditions were poor in Germany and the Rhinemetal-Borsig factory was over run before production could begin.

I believe it could have been in service much earlier since development had been paused in 1940 for about 2 years. It was actually a very cheap fuse to produce, cheaper than the clockwork fuse and much cheaper than the allied radio fuse. The Germans had suspended work on this fuze when they were trying to muster resources for weapons that could be produced quickly during the war with France which the feared they would loose.

Despite handing over their work to the USA the British, perhaps because of national pride, continued some development of the fuse. They succeeded in detonating by remote control a few rounds in 1942. The Description is given in Louis Brown's Book. Radar, Technical and Military Imperatives.

The British intended to use radar to track the shell via a corner reflector. Then when the reflection of the shell merged with that of the target they planned to detonate the shell via a double radar pulse. The US fuse was further along, more flexible and the British lacked resources. Anyway, they proved they could shock harden a proximity fuse.

I'll give a quick run down on how the US fuse was shock hardened before describing the German fuse.

It's a provable law of mechanical stress that scaling an item 10 times smaller will make it 10 times more shock resistant. This was one of the key's to how the US fuse was developed. For instance Vacuum tubes developed for the V2 rocket could withstand 50g which is 10 times the acceleration the V2 could produce. Had they tube been scaled down by a factor of 10 it would have operated at 500g (still short of the 10,000g needed)

The US tubes were modified to shock harden them in many ways, repeatedly tested. The basic technique was to replace cylindrical electrodes with disk shaped planer ones. Initial tests with a standard miniature vacuum tube developed for hearing aids was very promising. The tone oscillator used in tests not only often survived drops from great heights on to concrete but launches from a relatively low velocity 37mm gun.

The vacuum tubes were held in place with wooden blocks and the space filled with oil so that the tube was neutrally buoyant. Thus when fired the oil was pressurised by the acceleration it was even throughout the envelope of the tube.

The German fuze worked of the electrostatic field generated by an aircraft as it moved through the air. This is massive. When the US started developing its Strategic Defence Initiative to destroy ballistic missile they developed an electrostatic fuse to destroy MIRV. It shouldn't be regarded as inferior. The shell also develops a field around itself and the gradient caused by an aircraft effecting the field will also be detectable. Electrostic proximity fuses are almost impossible to jam but they degrade rapidly in rain (the reason the USN Buro Ord didn't develop them)

The German fuse worked using a type of vacuum tube called a cold cathode tube (glimmer relais in German which translates into glow lamp relay). These tubes were already being used to set time delays in German air dropped bombs and so were already shock hardened. In fact examination of the German shock hardened time delay bomb fuses was what triggered the British to re-examine the proximity fuse work they had attempted in 1932.

The tube was actually filled with 0.5 atmospheres of argon gas and had 3 electrodes.
1 Cathode on to which the negative terminal of a battery or precharged capacitor was connected.
2 An anode which was connected to the positive side.
3 a second or 'striking anode' which was arranged to be between the above cathode and anode. If a small positive voltage was applied to the striking anode the argon would ionise between the cathode and striking anode and then carry over to the main anode and carried a large current. This could be used blow a wire fuse that would set of a primer.

Because this kind of tube lacked a heater element it was very tough and shock resistant. It also didn't need a battery and could work of a simple and rugged precharged capacitor.

The fuse worked a follows there was an antenna on one side of the shell, actually a small whip aerial about 4cm long, hanging of the tip of the 8.8cm shell. As the shell rotated at 18000rpm or (300 cycles/second) it would alternately come closer and then further away from the electrostatic gradient of target aircaft. This presented as a 300Hz alternating current in the shell. It was filtered and possibly rectified rectified (via copper oxide diode) and if a sudden and strong increase in field occurred the voltage would exceed the striking voltage of the striking anode and the shell would detonate. A nose contact fuse, essentially a push button electrical switch was also provided to blow up the shell.

In order for a standard 88 shell to destroy a bomber it had to detonate within 3.0 to 3.5m. Detonation at 10m would typically only produce survivable damage.

Hence when the German had the fuse working at 5m in 1943 they had enough to have a useful proximity fuse.

It's interesting to note that toward the end of the war that the Germans had worked out that a simple nose contact fuse was more effective than a time fuse. Complex expensive fuses, powerful high grade explosives and fragmentation cases produced an expensive shell in addition there was a lot of effort put into setting the fuse that reduced the firing rate. It was better to just go for a direct hit both in terms of expense and the number of aircraft brought down.

Hence the German electrostatic fuse, which was cheap to make, would have been quite good since it was a kind of nose contact fuse with proximity plus.

The Germans also planned to use this 'cold cathode' technology to produce electronically programmable time delay fuzes for the canon shells. They worked much the same way as the time fuzes used in some German bombs. A capacitor was precharged to a voltage that set the time delay, this discharged via a resistor into a second capacitor. When the voltage in the second capacitor reached a certain level it would reach the striking voltage of a cold cathode tube and detonate the shell. An acceleration switch in the shell would begin the timer.

The idea was to mass produce the components, age them a little, test them and sort them into batches so that they could be assembled into fuses with consistent time characteristic. A batch of resistors with a too high a value might be combined with cold cathode tubes with low trigger voltages. An adjustable trimming device would have completed the adjustment.

Obviously the electrostatic proximity fuse and the electronically programmable time delay might be combined into a single fuse. It would require only two tubes instead of one. By contrast the allied fuse needed 6 or 7 vacuum tubes and an expensive battery.

Hence one could imagine these fuses fired at aircraft, perhaps a 1/4rd blowing up too soon but the remainder either detonating at the desired point, triggering of the aircraft or achieving a direct impact or if they missed by a large margin blowing up above the aircraft.
 
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MT fuzed shells striking an A/C would have rendered the fuze unservicable, causing duds and low order detonations. D.Z. fuzed AAA shells would be able to explode always high order on predefined time or impact, depending on which circuit was closed first. Rate of fire very significantly improved with D.Z. shells (similar to AAA firing VT-fuzed shells enjoying this nice side effect).

Actually the VT fuses that were "duds" in the air often detonated when they hit earth/water at the end of the flight if there was enough power left in the capacitor. While there was no separate contact fuse mechanism the firing circuit was controlled by a reed switch and if the shell landed in a fashion that allowed the reed switch contacts to meet the shell would detonate (again, given there was enough power left in the capacitor.)
Interestingly the Navy fuzes, and thus the vast majority of Allied VT fuzes had no self-destruct mechanism. Not a big deal if you are firing over water and away from land. Not such a good idea if used for defending a major city. British anti-diver belts of AA guns were NOT placed in areas with high populations.

How effective the 88mm gun would have been with Allied style VT fuzes is also a question. The US 3" shell needed to explode much closer to the target than a 5" shell or more of them were needed to get the same effect. In a 5" shell the amount of explosive displaced by the larger fuse was negligible in comparison to the total amount of explosive. In the 3" shell the amount of explosive displaced was a much larger percentage of the total despite the fuze being considerable smaller (and lighter). The British 3.7" AA gun used a sort of intermediate fuze between the two and the British shell with normal fuse went 28lbs compared to the 20.7lbs of the 88mm standard shell. The Fuse for a US 5" naval gun weighed over 6lbs. For the 3" gun they got it down to 2.40 lbs.

The 88 would be more effective than with standard fuses, just don't use the same multiplier for effectiveness that you use for the bigger shells and also note that just because you have fuse that works in 5" or 4" inch guns don't think that you have one that works in 3.5" guns.

I would also note that the Americans (I have no information about the British one way or the other) had built and tested proximity fuse jammers and after a stock of shells was captured during the Battle of the Bulge a rush order for 200 jammers was placed. I have no idea if they made it to Europe or were ever used if they did make it.
 

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