while the websites are interesting there is zero data on effectiveness.
Those 90mm guns with VT fuses & director FCS .....Any data on how ineffective they were without these trinkets.
Nazi better weapons enter service a year earlier.
- Thread starter Musketeer513
- Start date
while the websites are interesting there is zero data on effectiveness.
Those 90mm guns with VT fuses & director FCS .....Any data on how ineffective they were without these trinkets.
Deleted member 1487
You're the one claiming a positive knowledge to their inaccuracy, do you have some evidence to support that claim? The segmented sabots that the Germans were developing were very easy to separate and caused little to no inaccuracy, while the British type 'pot' sabot had problems that was only figured out post-war.
What does the 90mm with VT fuse have to do with the discussion of how inaccurate or not saboted rounds were at the time? They were engaging very low flying V-1s at no more than 1000 meters. Supposedly some without VT fuses were used to engage some German bombers at night striking Paris with good results, but no info about the altitude of the German bombers nor how many were hit by the P-61s that intercepted and how many were downed by the 90mms.
marathag
Banned
US 90mm AAA went from 2500 shells per V1 to 100 once the analog computing M-9 Director and 10cm SCR-584 were used with VT fuzes
http://ed-thelen.org/pre_nike.html
Deleted member 1487
Engaging targets at 900m, the operating height of the V-1. We were talking about using sabot round to hit targets at 8000m, about 9x as high. Even with the superb SCR-584 and VT fuses the same problem of time to altitude and dispersion/effective engagement height was still there. Which is why the Brits adopted a faux sabot solution:
https://en.wikipedia.org/wiki/QF_3.7-inch_AA_gun#Mk_VI
The Germans were experimenting with the same method for the 128mm FLAK 40 in 1945, calling it the FLAK 45.
marathag
Banned
Radar info for the SCR-584
Maximum Range
PPI Search
70,000 yards (39.7 statute miles)
Auto-Track
32,000 yards (18.2 statute miles)
Potentiometer Data
(artillery control)
28,000 yards (15.9 statute miles)
Minimum Range 500 - 1000 yards
Lower Elevation Limit -175 mils (-9.8 degrees)
Upper Elevation Limit +1,580 mils (+88.9 degrees)
Azimuth Coverage 360 degrees
Azimuthal scan rate in search mode 5 revolutions per minute
Range Error 25 yards
Azimuth Error 1 mil (0.06 degree)
Elevation Accuracy 1 mil (0.06 degree)
Accurate range and the Prediction from the Director is what allowed the VT fuze to work so well.
Computer was set to calculate time of flight, and effect of gravity on the shells flight to get the 90mm aimed right
Deleted member 1487
ok, again engaging targets at 900m not 8000 or more. We have no data about how well they would do the job against high flying bombers in different weather conditions, as dispersion increased substantial the further a shell travels as it slows down, dropping from the supersonic to subsonic level while the spin speed slows and wobble increased, and has to deal with different atmospheric conditions. The longer it takes to get to altitude the more bombers had time to maneuver even slightly to throw them off their predicted aiming point, even slowing down slightly or speeding up. If the US 90mm round took as long as the basic German 88 to get to altitude even with better radar guidance issues still remain.
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That leaves quite a bit of leeway, especially IMO for the Type 21. Introduced 6mo or a yr earlier, it could have been an Allied nightmare. Trouble was (& this is an issue for many of these), Dönitz saw no need for such a dramatic improvement in sub tech... So, how do you persuade him? (Forget the Walther boats; they were insanely dangerous
for limited gain.)Actually, the Type 21 was almost as big a change for Allied ASW as Nautiluses would be.
And I'm not overstating that for effect. The Type 21's dived endurance wasn't as great, but speed was enormously greater than the Type 7/Type 9, and they were quieter. The Allies would've needed something like heliborne ASW torpedoes, which would have to be at least twice as fast as the Mk24, with greater endurance for search, plus air-delivered (heliborne?) sonobuoys (possibly dipping sonar), plus (probably) better passive & active shipborne sonars. Bigger convoys would be good, too. So would better air cover. Corvettes would be so much junk; a dived Type 21 could outrun one. (Rickover rightly saw Nautilus had changed everything; truth be told, the Type 21 could have, too, had it appeared in time--& had Dönitz & Co started with a more/less conventional Type 9 pressure hull with a new casing, & none of the fancy gimmickry of hydraulic torpedo loading & such, a "stripper" version could have been in service in 1942 with ease. Except Dönitz, rightly, saw no need for it...)
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http://ed-thelen.org/pre_nike.html
good starting article. So the FCS/VT improved the shooting from 2500 down to 100 or 1/25th....vs 400mph V-1 @ 1KM altitude.
How the hell did spitfires even catch V-1 at 400mph??? The best level speed they could manage @ 1km was only 360-370mph.
http://www.spitfireperformance.com/spitfire-XIV.html
Maybe that explains the 351 allied planes lost [+ 805 crew] shooting the V-1 down
https://en.wikipedia.org/wiki/V-1_flying_bomb
good starting article. So the FCS/VT improved the shooting from 2500 down to 100 or 1/25th....vs 400mph V-1 @ 1KM altitude.
How the hell did spitfires even catch V-1 at 400mph??? The best level speed they could manage @ 1km was only 360-370mph.
http://www.spitfireperformance.com/spitfire-XIV.html
Maybe that explains the 351 allied planes lost [+ 805 crew] shooting the V-1 down
https://en.wikipedia.org/wiki/V-1_flying_bomb
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That leaves quite a bit of leeway, especially IMO for the Type 21. Introduced 6mo or a yr earlier, it could have been an Allied nightmare. Trouble was (& this is an issue for many of these), Dönitz saw no need for such a dramatic improvement in sub tech... So, how do you persuade him? (Forget the Walther boats; they were insanely dangerous
Actually, the Type 21 was almost as big a change for Allied ASW as Nautiluses would be.
Yeah if sub submerged speed is increased from 5 knots to 10 knots the ballistic ASW effectiveness is cut in 1/2, mostly because the area needed to cover- in a 10 SECOND attack- is quadrupled [2,000m^2 Vs 8,000m^2 ]. If that speed is increased to 15 knots submerged the ASW ballistic effectiveness figure is roughly 1/4 , mostly because the area to be covered in 10 seconds- is about 18,000m^2.
It was a game changer, but most of the speed increased could have been squeezed out of the Type-VII & TYPE IX U-Boats mid war as well as Snorkel capability.
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I believe your cited site for Spitfire performance shows the performance graph established at Farnborough for Tempest V, Spitfire XIV and Mustang III, specially prepared for Noball service evaluation. The Mosquito was second in total shoot-downs after the Tempest V, followed by the Spit and Mustang. Your Wiki figure for losses may include attacking launch sites, heavily defended by flak. Otherwise, there are too many crew for single and two-seat aircraft.
In the case of the Mossie FB VIs, level speed didn't factor in because of tactics employed. They dove.
Diving only gives you one kick at the can...if you can't match the speed it sounds like it was not enough.
Look at the overall data. BOB 90,000 LW sortie were countered by 88,000 RAF sortie during which ~ 3000 LW planes were shot down.
MINI BLITZ 45,000 allied sortie were needed to counter 8000 V-1 sortie, of which 8000 shot down[???]
MiniBlitz needed 6 times as many allied sortie to kill each V-1 sortie.
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You may not be overstating for effect, but you are overstating. The Type XXI was a big improvement, but it still had significant problems:Actually, the Type 21 was almost as big a change for Allied ASW as Nautiluses would be.
- Submarines were detectable on radar and visually when schnorkelling, and vulnerable to attack from VLR aircraft. Being nuclear powered, Nautilus never needed to return to the surface.
- A submerged submarine is virtually blind, and if unable to schnorkel has very short legs. Without VLR air support of their own, or the B-Dienst being able to read the Allied codes, finding a convoy in the North Atlantic is actually very difficult - and a submerged Type XXI will actually have a harder time of it than the surfaced Type VIIs did due to the much lower horizon for lookouts.
- Corvettes weren't the only escorts by 1944, and even then the speed advantage of a Type XXI over even a Flower class is a bit marginal (remember that the maximum speed given is only possible with a fresh battery - unlikely to be possible if the convoy has air cover) - to give you an example HX 293 was escorted by:
- Setter was a whaler so very slow (10 kts?)
- Brockville, St Boniface were minesweepers (16 kts)
- Atholl, Brandon, Buctouche, Collingwood, Dundas, Lethbridge, Matapedia, Nanaimo, North Bay, Quesnel, Sorel, Trail, Vancouver were of the Flower class (16 kts)
- Montreal & Wentworth were of the River Class (20 kts)
- The allies had sonobuoys and homing torpedoes (Mark 24) in service from 1942, sinking their first victim in May 1943. The low speed of the Mark 24 isn't that big an issue - yes, a Type XXI could outrun it, but in so doing would deplete it's battery and make itself an easy target for tracking by sonobuoys. Operating from escort carriers the USN and RN could stay above it all day long if needed, until it either surfaced to be bombed or ran out of battery and a Mark 24 could catch it.
Wouldn't greater production of FW 200 Condors designed for dropping paratroopers have been more effective since they could hold more troops and fly 50% faster than a Ju 52?
Deleted member 1487
It wasn't a mass produced aircraft, which is a major issue. I mean yes, it would have been a better option for that, but much more expensive and then not available for the naval war; the first FW200 that wasn't a civilian airliner was actually developed on a naval recon prototype contract for the Japanese Navy, but the war broke out before the batch could be delivered and the Luftwaffe took them. Finding them the only long range aircraft available they Germans started batch producing more, but didn't have dedicated lines for them for a long time and then all went to the naval war as available.
Good luck trying to convince the Luftwaffe to cancel the cheap Tante-Ju for large, more expensive, non-mass produced FW200s. The only reason the Ju-52 was kept forever was because it was so cheap to make, having been produced since the mid-1930s and did not have retractable landing gear. Also faster isn't always better in terms of dropping paratroopers. And frankly the Ju89/90/290 might have been even better than the Fw200.
Now if the Ju290 was available a year early you might have some interesting impacts all around too:
https://en.wikipedia.org/wiki/Junkers_Ju_290#Operational_history
Cancel the He177 and just use that for all sorts of things, both naval and land.
If you have FW200 production and technical development levels in 1940 that you had in 1941 and in 1941 what you had in 1942....then things can get interesting.
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German U-Boats had GHG ultra low frequency passive sonar [from the beginning of the war ] that was capable of detecting big fast warships @ 20-30km , while detection of convoys @ 50km distance was common place due to the large number of noisy merchant vessels. KM OS allowed them to map out allied convoy systems and through mid war [41-43] they detected 1/2 of all convoys in the North Atlantic. However only 1/2 of those detected convoys were being attacked by the WOLFPAKS , since the allied suppression of the WOLFPAKs was driving them underwater crippling their searching capability The allied ASW effort was increasing based on the increasing HF/DF intercepts of U-Boat radio transmissions, and the Intel 'Ultra' provided from late 1943 on.
Trouble was most of these counter moves were anticipated prewar , but dismissed by Donitz. Donitz appears to have been obsessed with his U-Boat as weapons , and once his WOLFPAKs were established, so to were his credentials with Hitler.
Prewar criticism however predicted that once the enemy deployed enough ASW assets- the WOLFPAK system would be driven below the waves and finished as a strategic factor. Further this critique anticipated that prolonged radio communications would lead to enemy attacks through enemy HF/DF. Better use of LW/KM surveillance was demanded- as a work around. This too was dismissed by the LW & Donitz....although that would be reversed late war when Hitler demanded the AMERIKA BOMBER.
So yes more CONDORS for the KM would be a good starting point. A POD start point could be KM dissolving all its prewar seaplane production plans in exchange to adapt LW aircraft already in production. They could end up with doubled the number of Condors built but build 1/2 as many seaplanes.
Trouble was most of these counter moves were anticipated prewar , but dismissed by Donitz. Donitz appears to have been obsessed with his U-Boat as weapons , and once his WOLFPAKs were established, so to were his credentials with Hitler.
Prewar criticism however predicted that once the enemy deployed enough ASW assets- the WOLFPAK system would be driven below the waves and finished as a strategic factor. Further this critique anticipated that prolonged radio communications would lead to enemy attacks through enemy HF/DF. Better use of LW/KM surveillance was demanded- as a work around. This too was dismissed by the LW & Donitz....although that would be reversed late war when Hitler demanded the AMERIKA BOMBER.
So yes more CONDORS for the KM would be a good starting point. A POD start point could be KM dissolving all its prewar seaplane production plans in exchange to adapt LW aircraft already in production. They could end up with doubled the number of Condors built but build 1/2 as many seaplanes.
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thaddeus
Donor
my scenario is earlier development of guided munitions, a little Fritz-X if you will, for a fleet of FW-200s and Dornier DO-24s, two aircraft with established commercial value and using the surplus Bramo radials.
not sure if wire guided SC-250 bomb would be considered a wonder weapon but probably would be effective for a time?
You'll recall I said "almost".
Where did I say Type XXIs would always remain submerged?
And if the Type XXI is in service a year sooner than OTL, air cover is unlikely, & the main escort is likely to be about 3 Flowers.
Which presupposes sonobuoys & a/c to track them with; given early introduction of the Type XXI, neither is likely to be on hand.
Operating from escort carriers the USN and RN could stay above it all day long if needed, until it either surfaced to be bombed or ran out of battery and a Mark 24 could catch it.
That said, by 1944, no U-boat is exactly safe...but before that, the Allies are in big, big trouble...
(And don't forget, most sinkings were of solitary ships anyhow.)If you're using "almost" to mean "several orders of magnitude less effective", then OK.You'll recall I said "almost".
If they don't, they're dead. From 1943 onwards air cover made running on the surface suicidal - by 1944 this had extended to the centre of the Atlantic around convoys.Where did I say Type XXIs would always remain submerged?
The first war patrols were in 1945, so I deliberately gave you the escort for a typical summer 1944 transatlantic convoy - 13 Flower class, 2 River class, 2 minesweepers and a trawler. By summer 1944 the US and UK had 50 Casablanca class escort carriers, 45 Bogue Class and another dozen conversions in service, plus significant numbers of VLR patrol aircraft. If 1944 convoys weren't getting air cover it's because they didn't think they needed it, not because it wasn't available.
See http://www.navairdevcen.org/PDF/THE EVOLUTION OF THE SONOBUOY.pdf - by 1944 the US Navy had already dropped thousands of sonobuoys from both land based and carrier aircraft, and had another 60,000 on order. Bring in a Type-XXI a year early and that's about the time sonobuoys were coming into service anyway
Only early in the war - once the convoy system was properly up and running there were very few of these left to shoot at.That said, by 1944, no U-boat is exactly safe...but before that, the Allies are in big, big trouble...
[QUOTE="wiking, ...................
Good luck trying to convince the Luftwaffe to cancel the cheap Tante-Ju for large, more expensive, non-mass produced FW200s. The only reason the Ju-52 was kept forever was because it was so cheap to make, having been produced since the mid-1930s and did not have retractable landing gear. Also faster isn't always better in terms of dropping paratroopers. And frankly the Ju89/90/290 might have been even better than the Fw200............. [/QUOTE]
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Ju 52 was reliable and in production during 1939. Even if Ju 52 was not the most productive transport it was still good for short-range deliveries. By late war, they learned that jumping farther than your artillery could support was suicidal!
A fictional Ju 152 would be similar in size to Ju 52, with the same engines, but fly farther and faster because of smooth external lines. Our fictional Ju 152 would still have corrugated skins, they would just be the second smooth layer brushing the wind aside (aka. Shorts Skyvan). Control surfaces would remain corrugated to ease production (aka. modern Cessna and Piper light singles). Wing flaps and ailerons would need to move up into the trailing edge to reduce drag and icing.
Ju 152 undercarriage would still be fixed, but good streamlining would help improve cruise speed towards the 200 knot range.
Fixed undercarriage only becomes a disadvantage faster than 200 knots or if icing is encountered. More recently, Cessna Caravan lost its flight into known icing conditions certification in Canada because all those struts ice up too easily.
ATL was thinking more in terms of more Ju 252 and 352 joined by Gotha and Arado transports with tail ramps to drop anti-tank guns and light vehicles.
An earlier poster as correct in stating that dropping paratroopers at faster airspeeds can exponentially increase malfunctions because parachute malfunctions increase with the SQUARE of the airspeed. Consider that modern C-130 Hercules still slow to 130 knots for jump run.
Good luck trying to convince the Luftwaffe to cancel the cheap Tante-Ju for large, more expensive, non-mass produced FW200s. The only reason the Ju-52 was kept forever was because it was so cheap to make, having been produced since the mid-1930s and did not have retractable landing gear. Also faster isn't always better in terms of dropping paratroopers. And frankly the Ju89/90/290 might have been even better than the Fw200............. [/QUOTE]
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Ju 52 was reliable and in production during 1939. Even if Ju 52 was not the most productive transport it was still good for short-range deliveries. By late war, they learned that jumping farther than your artillery could support was suicidal!
A fictional Ju 152 would be similar in size to Ju 52, with the same engines, but fly farther and faster because of smooth external lines. Our fictional Ju 152 would still have corrugated skins, they would just be the second smooth layer brushing the wind aside (aka. Shorts Skyvan). Control surfaces would remain corrugated to ease production (aka. modern Cessna and Piper light singles). Wing flaps and ailerons would need to move up into the trailing edge to reduce drag and icing.
Ju 152 undercarriage would still be fixed, but good streamlining would help improve cruise speed towards the 200 knot range.
Fixed undercarriage only becomes a disadvantage faster than 200 knots or if icing is encountered. More recently, Cessna Caravan lost its flight into known icing conditions certification in Canada because all those struts ice up too easily.
ATL was thinking more in terms of more Ju 252 and 352 joined by Gotha and Arado transports with tail ramps to drop anti-tank guns and light vehicles.
An earlier poster as correct in stating that dropping paratroopers at faster airspeeds can exponentially increase malfunctions because parachute malfunctions increase with the SQUARE of the airspeed. Consider that modern C-130 Hercules still slow to 130 knots for jump run.