Could proximity fuses have halted the bomber offensive against Germany in 1944?

[swampyankee]

One of the things being forgotten in this discussion is that in the WWII era, the U.S. probably had the best overall mix of technological and managerial methodologies for mass production, largely driven by the desire of companies to maximize overall profits, vs profit rates, i.e., make 10¢/widget for a $1 widget for 50,000,000 widgets vs $10.00/widget for a $50 widget and selling 50,000 widgets.

 

[bbear]

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

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

Shotround6 You are quite correct that I misinterpreted my text I think. Pleas understand 70ft was a distance established in experimentation. I was trying to think why that distance would be optimum. here's the key quotation in "The Deadly Fuze" Ralph B. Baldwin Presidio Press 1980 page 135
The assemblage essentially eliminated ground reflections permitting accurate measures of the fuze burst patterns . . .

Up to is point T section had been simply been guessing at the right frequency . . . . but it was clear that the fragments went sideways and forwards in a cone.

After about a hundred runs with the reduced scale fuze and plane a three dimensional model of burst locations was built up When multiplied by the fragmentation patterns of the shell one could determine.he number of fragments that would pass through the plane . . .

Luckily the shape of the shell as an antenna and the kind of electrical circuits that could be used in a VT fuze forced the fuze to trigger before it reached the target Consequently only minor adjustments were required to match fuze and fragmentation patterns to optimise burst efficiency.

. . .

Fuze sensitivity was the only variable that could be changed greatly . . . There was a broad spectrum of fuze sensitivities that yielded nearly optimum burst patterns. Almost all of the good fuzes would operate about seventy feet from the plane with a few bursting as much as far away as a hundred feet.

..


. . full scale tests corroborated the reduced scale patterns.

. . .
A team of experts examined the plane for damage after each round to assess if any specific fragment would be damaging enoough to to bring down the plane immediately or later

more to follow, sorry for the delayed response. My Parkinson's condition means I must harbor my resources before approaching a keyboard and I've been ttrough some life changes..

 

[Shortround6]

Thank you for your reply. I am sorry to hear of your health issues and hope things are going as well as can be expected for you. Hope this forum can be a distraction.
No reply needed unless you are up for it. You do bring good information.

 

[bbear]

Thank you for your reply. I am sorry to hear of your health issues and hope things are going as well as can be expected for you. Hope this forum can be a distraction.
No reply needed unless you are up for it. You do bring good information.

Thanks
The same book p139 gives a table of shell efficiencies listing blast area ad lethal area using standard (D) and rdx (A) type explosives
i won'#t copy the whole table
fuze gun explosive filler burst area letal area my calculation lethal radius
sq. feet
mk32 5"/38 D 6,000 3,300 32ft 10meters
MK53 5"/38 D 18,000 5,200 40ft 12.8 m
Mk53 5"/38 A 18,000 6,800 46ft 14.8 m
Mk 47 6"/47 D 18,000 9,000 53ft 16.2 m
That's 'lethal' as defined by expert examination as mentioned before
This data was using a Nakajima 97 'Kate' in head-on approach /aspect (the most effective)
other planes tested included a Baka, B26,B17 and B24 and more but Kate figures usually applied to the others (I guess in area)
the differences being in vulnerability (i think they mean as oppose to size). The number of VT fuzes produce in toto in thhe aris 22.1 miion of whuich 1.8% were sent for test purposes Rear Adml,. G. F . Hussey in Foreword 2. Foreword 1 is by Merle. A Tuve colmpares 'blundering effectiveness' of e vs "top down" of autocracies as being the key to German failure and Allied success at war technologies. As long as aims were kept very clear the two way criticisms of worker to supervisor to science officers to management to government and vice versa meant that the solution was quickly arrived at. Whereas a simple hierarchical obedience resulted in time wasted. He was reflecting on the findings of the technical teams sent into Germany after the war. He ends his Foreword "We learned from each othernew things about the meaning of responsible American citizenship"

You may feel as I do that a shell would be most effective at extreme range at an approaching plane or fired along the close trajectory of a diving plane. The flattening out of the trajectory towards end range would give the 'swept volume' of 140ft diameter 'tube' for each shell the maximum chance to contain the approaching aircraft. The fleet action effectiveness of VT fuzes in the Pacific were 3:1 in other words if an action would result in 1/3 enemy losses using conventional fusing with VT they would be wiped out. I don't have the page reference right nw.

 

[Kaleun]

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]

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]

 

[Kaleun]

The problem of miniaturizing vacuum-tubes (initially these were derived from hearing aid devices) was solved by the end of 1942--the "ruggedized" tube could create a radio transmitter-receiver that would detonate a 5 inch AA shell about 75 feet from a hard target (including the ground). This was developed at the Johns Hopkins Applied Physics Laboratory following organization of the OSRD in 1940. Once the signal was received, the shell would expose--shrapnel would easily dispose of a Kamikaze or Japanese fighter, the most important pressing need early in the U.S. contribution to the war. On January 15, 1943, the VT (Variable Time) Proximity Fuze was first successfully used in the Pacific Theatre, fired from the U.S.S. Helena. Watch a History Channel documentary and you will see interviews with Japanese pilots describing their comrades' planes dropping from the sky without a direct hit. It wasn't necessary.

Production VTs could withstand 48,000 muzzle r.p.m. and multiple G-forces. James van Allen (of the van Allen belts) was overall director of the project. He was commissioned Lt. (j.g.) and sent to the Pacific to "sell" the fuze. Patton called it the "funny fuze.." Forrestal credited it with winning the war (top 3 developments).

The fuze crossed the English Channel, after being adapted for artillery use. SHAEF orders were that it not be used unless absolutely necessary, which came after December 15 with the Battle of the Bulge. As an anti-personnel shell, it caused German soldiers to seek hard shelter, as shrapnel easily penetrated helmets. Bounce-back signal for detonation was enough to send soldiers scurrying for shelter. Prior to December, the U.S. was most concerned that the Germans would find a live shell and reverse-engineer it. I know of no evidence this was used on V-1 or V-2s for defense.

By the time of Vietnam, VT shells were routine. A contact exploder was a special request item. However, despite tantalizing general-press articles, the VT was not fully declassified until 1976. The first authoritative book on development and testing was by R. Baldwin, "The Deadly Fuze, " 1980. Baldwin Published a 2nd book, "They never knew what hit them," 1999, Naples, FL, with more first-hand accounts (e.g. from Germans in the Battle of the Bulge).
I personally have 2 such warheads, an "award shell," and an inert 1944 shell. Baldwin and Dr. R. H. Herman were the liasons to the Navy and Army as the shell was developed.

A related problem was the Mark 14 torpedo, available in masses in 1941. However, many such torpedoes were ineffective, turning around to strike the firing submarine. These were contact/magnetic detonated torpedoes. Magnetic detonation was unreliable and ordered by CNO to be turned off by the end of 1942.
A reliable contact/magnetic firing torpedo was a major project (Einstein was a contractor on this), with a reliable Mark 10 Torpedo Exploder Mechanism appearing in early 1945, dropped from TBM bombers in the Pacific. Innovative uses of magnetic detection and destruction (Magnetic Anomaly Detection) from bombs dropped on submarines from seaplanes were effective by mid-war.

The Proximity Fuze was a great a achievement. When 3 of 4 dummy airplanes were destroyed in final testing, the 4th test target was saved. 75% accuracy was well above what was sought, and the fuze went into production immediately. "Need to know" was an important factor in assembly--many manufacturers not involved in final assembly had no idea what they were making.

 

[Barrett]

Fascinating discussion with much skookum info.

So happens I'm reading Westermann's encyclopedic Flak study--not being a big arty guy, I've seen nothing remotely comparable. Checked the index but find no references for fuzes.

Been awhile since I looked at ETO/MTO bomber losses (not since the 15AF history) but I think generally Flak accounted for about 1/3 of heavy bomber losses, though that may have been known losses to enemy action, exempting operational/weather related.

FWIW:

One of my antiquer buds in California was a really bright guy who attended Cal Poly (IIRC) during the war. He and a handful of other gifted students were put to work on very specific research projects, and they were Prohibited from talking to each other about their work, on penalty of Death Or Worse. That message was reinforced periodically by taciturn men in suits with no apparent sense of humor.

Well...you know what happened. The guys did talk, and they G2'd that it was The Deadly Fuze. But they were really (really) quiet about it and escaped Consequences.

I'm mostly a PTO kinda guy and somewhere have a couple of studies showing the effectiveness of USN AA weapons. IIRC one of them noted that the VT gadget was accepted for distribution when the failure rate fell below 50%.

 

[bbear]

The problem of miniaturizing vacuum-tubes (initially these were derived from hearing aid devices) was solved by the end of 1942--the "ruggedized" tube could create a radio transmitter-receiver that would detonate a 5 inch AA shell about 75 feet from a hard target (including the ground). This was developed at the Johns Hopkins Applied Physics Laboratory following organization of the OSRD in 1940. Once the signal was received, the shell would expose--shrapnel would easily dispose of a Kamikaze or Japanese fighter, the most important pressing need early in the U.S. contribution to the war. On January 15, 1943, the VT (Variable Time) Proximity Fuze was first successfully used in the Pacific Theatre, fired from the U.S.S. Helena. Watch a History Channel documentary and you will see interviews with Japanese pilots describing their comrades' planes dropping from the sky without a direct hit. It wasn't necessary.

Production VTs could withstand 48,000 muzzle r.p.m. and multiple G-forces. James van Allen (of the van Allen belts) was overall director of the project. He was commissioned Lt. (j.g.) and sent to the Pacific to "sell" the fuze. Patton called it the "funny fuze.." Forrestal credited it with winning the war (top 3 developments).

The fuze crossed the English Channel, after being adapted for artillery use. SHAEF orders were that it not be used unless absolutely necessary, which came after December 15 with the Battle of the Bulge. As an anti-personnel shell, it caused German soldiers to seek hard shelter, as shrapnel easily penetrated helmets. Bounce-back signal for detonation was enough to send soldiers scurrying for shelter. Prior to December, the U.S. was most concerned that the Germans would find a live shell and reverse-engineer it. I know of no evidence this was used on V-1 or V-2s for defense.

By the time of Vietnam, VT shells were routine. A contact exploder was a special request item. However, despite tantalizing general-press articles, the VT was not fully declassified until 1976. The first authoritative book on development and testing was by R. Baldwin, "The Deadly Fuze, " 1980. Baldwin Published a 2nd book, "They never knew what hit them," 1999, Naples, FL, with more first-hand accounts (e.g. from Germans in the Battle of the Bulge).
I personally have 2 such warheads, an "award shell," and an inert 1944 shell. Baldwin and Dr. R. H. Herman were the liasons to the Navy and Army as the shell was developed.

A related problem was the Mark 14 torpedo, available in masses in 1941. However, many such torpedoes were ineffective, turning around to strike the firing submarine. These were contact/magnetic detonated torpedoes. Magnetic detonation was unreliable and ordered by CNO to be turned off by the end of 1942.
A reliable contact/magnetic firing torpedo was a major project (Einstein was a contractor on this), with a reliable Mark 10 Torpedo Exploder Mechanism appearing in early 1945, dropped from TBM bombers in the Pacific. Innovative uses of magnetic detection and destruction (Magnetic Anomaly Detection) from bombs dropped on submarines from seaplanes were effective by mid-war.

The Proximity Fuze was a great a achievement. When 3 of 4 dummy airplanes were destroyed in final testing, the 4th test target was saved. 75% accuracy was well above what was sought, and the fuze went into production immediately. "Need to know" was an important factor in assembly--many manufacturers not involved in final assembly had no idea what they were making.

Thanks for that and good new information. Chapters 27 and 28 of The Deadly Fuze cover defence against V-1s of UK and the port of Antwerp respectively. For Antwerp batteries VT was made available in mid December 1944 and was in use after 1 weeks practice against tethered balloons wire covered (meaning 'chicken wire'?). The attack lasted 154 days starting 24th October 1944 ending by my calculation on 27th March 1945, about 4900 V1s used (10mn tons it says). Of these 4900 V1 2400 would have hit in the area of Antwerp port (not defined) but 2200 were shot down. Battery fire was 40% effective without VT. Eventually better than 90% of targets engaged were destroyed (Category A - exploded in air or Cat B winged exploded on ground contact). Overall defence including aircraft 91.2% 2183/2394 V1s that would have hit. typical engagement 60 seconds. Which by deduction it says means just about every v1 engaged by VT artillery was destroyed. Allied casualties 32 killed. Civilians not included I suspect.

Compare that with V1 over the channel 80 days 12th June to end of August. VT shells for the 3.7" guns arrived April 1944 and first became available shortly after the attack began. The 'roll out' of VT was such that by the beginning of August practically all the 500 guns had VT capability (including 5 btns of American 90mms) For the last 4 weeks of the 80-day attack the effectiveness was 24, 46, 67 and 79% of targets engaged were destroyed. Overall in the early weeks defences destroyed 40% and over the whole period of 100 V1s 46 were destroyed by defence forces, 25 inaccurate (sea or France), 29 got to London region. 9,300 launched in all. Casualties 5,500 dead (compared with 1st 4 months of the blitz 13,000 plus dead).

All the above is what the book says, summarised. I have mad no attempt to verify any of it.

My comment. Many innovations and improvisations, command decisions and re-deployments were made on both sides of the channel. Germans camouflaged their sites and launched in poor visibility by preference. Major replanning of batteries to the coast plus indicators. At Antwerp the technologies and employment seeem to have reached full potential. Comparing the two attacks, possibly VT technology by itself might improve top equipment and crew by about 60% from 40% to nearly 100% of targets engaged. A game changer. But that's just one source.

 

[swampyankee]

B Barrett

"Skookum?"

What does that mean?

------------------------

In answer to the OP:

One would hope not.

 

[Milosh]

Skookum is a Chinook Jargon word that has historical use in the Pacific Northwest. It has a range of meanings, commonly associated with an English translation of "strong" or "monstrous". The word can mean "strong",[1] "greatest", "powerful", "ultimate", or "brave". Something can be skookum, meaning "strong" or "monstrously significant". When used in reference to another person, e.g., "he's skookum", it conveys connotations of reliability or a monstrous nature, as well as strength, size or hard-working.

 

[Kaleun]

Not as well basically as against other planes. Short range signal and needs a return signal. If it got close too the engines then fine. Plus it was fast.
Then again the V1 was as fast or faster, and it worked real well against them. Though it was all metal of course.

But against a Lanc, or a B-17 or a B-24 .. ugly.

We were lucky they didn't crack it until too late.

But against a Lanc, or B-17 or B-24 ... would work real well...

 

[Kaleun]

My father was one of the team developing the Proximity Fuze, and I interviewed Ralph B. Baldwin in 2009. I also know Dr. Robert Herman very well. WGVU produced a documentary on the Fuze which is also very good--obtainable from that station. Electrostatics pose all kinds of problems--lightning ignition, etc., would not be effective as a Time on Target (above ground) detonator. I have studied the German and Japanese records and neither had a functioning Prox. Fuze before the war ended. VT (Variable Time) and Proximity are essentially used synonymously in the military. Time delay fuzes have never been very effective. As the Proximity Fuze was 75% effective in its final trial (against 4 drone aircraft), it passed the Navy's requirement of 50% effectiveness. I'm not sure how you can say that a development that is generally regarded as one of the top 3 things that won WW2 isn't interesting or exciting, but try reading "The Deadly Fuze." Imagine being recruited for a Classified project on the sidewalk after being invited from Wisconsin to D.C. for an "interview." That's how Dr. Baldwin, an Astronomer, was recruited. They (OSRD) simply wanted the best minds possible, as the U.S. knew it was technologically far behind Germany in 1940. Gearing up for the war was authorized in August 1940 although the U.S. was "neutral" until shortly after 12/7/41.

 

[Barrett]

Skookum is a Chinook Jargon word that has historical use in the Pacific Northwest. It has a range of meanings, commonly associated with an English translation of "strong" or "monstrous". The word can mean "strong",[1] "greatest", "powerful", "ultimate", or "brave". Something can be skookum, meaning "strong" or "monstrously significant". When used in reference to another person, e.g., "he's skookum", it conveys connotations of reliability or a monstrous nature, as well as strength, size or hard-working.

What Milosh said. Though I'm from the dryland part of the Great Northwest, "Skookum" was occasionally used as a compliment: astute/worthy/etc.

 

[Kaleun]

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]

 

[Kaleun]

If you are familiar with how Dr. Merle Tuve worked as an administrator, the Proximity Fuze, developed by Section T, NDRC, OSRD, teams were shuffled around depending on the task at hand--one could find oneself the "head" of one work group and a "worker bee" in another group, at the same time. Most of the posts made since I contributed to the Forum add correct information, with more detail (.e.g. what the British did with the "POZIT" fuze, their version of the VT acquired in 1944. I gave 2 references, but by Ralph B. Baldwin which are quite comprehensive. He published "The Deadly Fuze" 4 years after full declassification. After the ware there were several published "teasers" that we had something unique, basically what it did, but no technical data. I spent a week in the National Archives at College Park gathering material based on my father's classified work during the war, which included development of the Mark 14 Torpedo Exploder and also demagnetizing equipment for surface vessels and submarines. During the war, every Navy vessel was run through a demagnetization range, which were spread world-wide, at least every 6 months (this was a requirement, whether it happened for every vessel, would require examination of all ship's logbooks). My work on those subjects was published in The Submarine Review (2009-2011).

Regarding the technical information about taking down a plane from 75 feet, my recollection is that when the fuze was detonated, shrapnel was directed at the source of the return signal. Like a shaped charge, this was more destructive. Anti-personnel artillery fuzes exploded directing the charge toward the ground, accounting for the great fear German troops had of being out in the open. I've confirmed this myself with veterans of the Ardennesoffensive (Battle of the Bulge).
I do not think the fuze was very effective against V1 and V2 rockets. Otherwise, why would OKW and AH risk so much to try to take Antwerp, which put much of Britain back within range of late-1944 rocketry of Wernher von Braun? If anyone has published, verified data on this (rather than recollections of downed seagulls), please give the reference here.

 

[swampyankee]

If you are familiar with how Dr. Merle Tuve worked as an administrator, the Proximity Fuze, developed by Section T, NDRC, OSRD, teams were shuffled around depending on the task at hand--one could find oneself the "head" of one work group and a "worker bee" in another group, at the same time. Most of the posts made since I contributed to the Forum add correct information, with more detail (.e.g. what the British did with the "POZIT" fuze, their version of the VT acquired in 1944. I gave 2 references, but by Ralph B. Baldwin which are quite comprehensive. He published "The Deadly Fuze" 4 years after full declassification. After the ware there were several published "teasers" that we had something unique, basically what it did, but no technical data. I spent a week in the National Archives at College Park gathering material based on my father's classified work during the war, which included development of the Mark 14 Torpedo Exploder and also demagnetizing equipment for surface vessels and submarines. During the war, every Navy vessel was run through a demagnetization range, which were spread world-wide, at least every 6 months (this was a requirement, whether it happened for every vessel, would require examination of all ship's logbooks). My work on those subjects was published in The Submarine Review (2009-2011).

Regarding the technical information about taking down a plane from 75 feet, my recollection is that when the fuze was detonated, shrapnel was directed at the source of the return signal. Like a shaped charge, this was more destructive. Anti-personnel artillery fuzes exploded directing the charge toward the ground, accounting for the great fear German troops had of being out in the open. I've confirmed this myself with veterans of the Ardennesoffensive (Battle of the Bulge).
I do not think the fuze was very effective against V1 and V2 rockets. Otherwise, why would OKW and AH risk so much to try to take Antwerp, which put much of Britain back within range of late-1944 rocketry of Wernher von Braun? If anyone has published, verified data on this (rather than recollections of downed seagulls), please give the reference here.

Against the V-2, proximity fuzes were probably useless, as these were essentially primitive tactical ballistic missiles, and the fire control systems and fuze systems of the era weren't capable of intercepting V-2. The V-1, on the other hand, flew fairly slowly and straight and level; it was an easier target than a manned aircraft not on a collision course.

Antwerp was a major port. Letting the Allies have it would make the supply situation for the Allies much easier.

 

[bbear]

Kaleun, Sir
Regarding the technical information about taking down a plane from 75 feet, my recollection is that when the fuze was detonated, shrapnel was directed at the source of the return signal.
My best bellief is that basic ballistics makes a cone of debris forward in the line of flight. Downwards for a howiter shell.

Like a shaped charge, this was more destructive.
(what analogy is there? morre destrucive than blasst damage at 75ft? or more than a shrapneel cone pointing uupwards as it might be with a time fuze?)

Anti-personnel artillery fuzes exploded directing the charge toward the ground, accounting for the great fear German troops had of being out in the open. I've confirmed this myself with veterans of the Ardennesoffensive (Battle of the Bulge).
(there was no separate anti-personnel VT fuze, VT took out any soft targett inclluding entreched troops)

I do not think the fuze was very effective against V1 and V2 rockets.
(V1s aren't rockets van braun had nothing t do with their design AFAK. The fgures I gavee above seem to indicate otherwise)

Otherwise, why would OKW and AH risk so much to try to take Antwerp,
( it was the only deepwater port except Mulberry 1 UK AFAIK, Do you mean the Scheld/Walcharen Island? If you mean the bulge surelly that was an attempted encirclement)

which put much of Britain back within range of late-1944 rocketry of Wernher von Braun?
(V2 were launched AT Antwerp,not from it. )

If anyone has published, verified data on this (rather than recollections of downed seagulls), please give the reference here
(my dad was at Antwerp 1st Mountain Rgt RA. good enough?* apart from the Deadly Fuze, of course.)

*edit (by which I mean I have taken some trouble to read about Antwerp and the Battle for the Scheldt to a degree and I'm pretty confident, though I will check)

 

[bbear]

Subsidiary question. If the German Proximity Fuze had been fitted to V2 rockets and V1s thus giving guaranteed 'airburst', how much more destructive would they have been? Enough to justify the programs? They were terror weapons that didn't kill many people 3 deaths per V1 aimed at London at the beginning of the campaign 1944. to 1:1 at the end (the Deadly Fuze Chapter 27). And for the whole V2 campaign against London and Antwerp 1:1. (wikipedia). Airburst 2,000 lb bombs dropped by the Luftwaffe had disproportionate destructiveness. Yet no discussion AFAIK of bombs being considered for VT fuzing? The allies did later develop VT fuze Army rockets.

 

[Shortround6]

The VT fuse simply detonated the shell, the fragment pattern was pretty much the same as a time Fuse (not exactly because the VT fuse was larger and some of the HE had to be taken out to fit the VT fuse) and any thought about how shells flew and how they detonated would show that this is a fairy tale.
Same with effects against personnel on the ground. Getting air burst shells without the VT fuses was a combination of science and art. However it had been being done since the days of muzzle loading artillery and for the same reasons. the shell may burst in the air but the vast majority of fragments, even as they spread out, will retain some of the forward vector/velocity of the shell. Shells that hit the ground before exploding have a large portion of their fragments absorbed by the ground.
Shrapnel shells used just enough explosive to break the shell up/eject the shrapnel. Velocity of the shrapnel "bullets" was dependent on the velocity of the shell.

 

[bbear]

If you are familiar with how Dr. Merle Tuve worked as an administrator, the Proximity Fuze, developed by Section T, NDRC, OSRD, teams were shuffled around depending on the task at hand--one could find oneself the "head" of one work group and a "worker bee" in another group, at the same time. Most of the posts made since I contributed to the Forum add correct information, with more detail (.e.g. what the British did with the "POZIT" fuze, their version of the VT acquired in 1944. I gave 2 references, but by Ralph B. Baldwin which are quite comprehensive. He published "The Deadly Fuze" 4 years after full declassification. After the ware there were several published "teasers" that we had something unique, basically what it did, but no technical data. I spent a week in the National Archives at College Park gathering material based on my father's classified work during the war, which included development of the Mark 14 Torpedo Exploder and also demagnetizing equipment for surface vessels and submarines. During the war, every Navy vessel was run through a demagnetization range, which were spread world-wide, at least every 6 months (this was a requirement, whether it happened for every vessel, would require examination of all ship's logbooks). My work on those subjects was published in The Submarine Review (2009-2011).

Regarding the technical information about taking down a plane from 75 feet, my recollection is that when the fuze was detonated, shrapnel was directed at the source of the return signal. Like a shaped charge, this was more destructive. Anti-personnel artillery fuzes exploded directing the charge toward the ground, accounting for the great fear German troops had of being out in the open. I've confirmed this myself with veterans of the Ardennesoffensive (Battle of the Bulge).
I do not think the fuze was very effective against V1 and V2 rockets. Otherwise, why would OKW and AH risk so much to try to take Antwerp, which put much of Britain back within range of late-1944 rocketry of Wernher von Braun? If anyone has published, verified data on this (rather than recollections of downed seagulls), please give the reference here.

Kaleun, Sir. I'm not sure if it counts as publication but this video has been approved for release by APL the speaker is an author of 2 books

View: https://www.youtube.com/watch?v=LyDlq77GVPM

He has a lot more access, it seems, to relevant personnel and materials from the period than any I've seen. His conclusions on Naval use of VT and anti-V1 s contrast with yours I feel. His conclusion that Kamikaze attacks were a response to improved USN gunnery seems plausible. As for performance against V1s his conclusions mirror my mine, although mine are much less credible.

As to performance against B!7's it seems to me that a V1 at 2,400 feet might subtend an angle at the aiming observer about that of the total 'hit' area of B-17 box at 24,000 (10x the distance 10x the size). Taking the increase in effectiveness as 5x as in this source page 17. http://www.dtic.mil/dtic/tr/fulltext/u2/a421867.pdf And the number of rounds per kill of German AA in 1944 from parsifal in another thread as 16,000 (Prof. Westerham I believe). That would drop to !/3000 roughly.

If so that would be insufficient to make the USAAF or BG give up. But it might reduce B-17 bombing accuracy and increase losses. So some critical engagements might go the other way than historically. For example the degradation of fuel supply might be delayed leaving a better introduction for the Bulge with regard to tank fuel. Maybe?