Aircraft Economics the forgotten consideration

[MikeMeech]

Not at all, my father spent the whole war on escorts protecting convoys in the N Atlantic and Arctic before going to the far east. He was interred with Merchant seamen in Russia. The whole principle of the Liberty ship was to ensure production exceeded losses. I was just discussing the principle, convoys were not halted due to losses, to wait for new technology as various other campaigns were like leaning into France, RAF daylight raids in 1940 and US daylight raids in 1943. Millions of men lost could not be accepted but tens of thousands could, just a question of magnitude not principle.

Hi

Reference "principle" this was as laid down in the February 1939 edition of the RN's 'Anti-Submarine Warfare manual' this confirmed: "... the value of convoy by increasing the difficulty of U-boats in finding targets and, where intelligence was available, of diverting shipping clear of U-boat concentrations." When ULTRA information was available it was most useful in this latter task for much of the war. The whole point was to get the convoy through with minimal losses. (source 'The Royal Navy and Anti-Submarine Warfare, 1917-49' by Malcolm LLewellyn-Jones, page 16).

Mike

 

[pbehn]

Hi

Reference "principle" this was as laid down in the February 1939 edition of the RN's 'Anti-Submarine Warfare manual' this confirmed: "... the value of convoy by increasing the difficulty of U-boats in finding targets and, where intelligence was available, of diverting shipping clear of U-boat concentrations." When ULTRA information was available it was most useful in this latter task for much of the war. The whole point was to get the convoy through with minimal losses. (source 'The Royal Navy and Anti-Submarine Warfare, 1917-49' by Malcolm LLewellyn-Jones, page 16).

The minimal loses were 14,million tons and around 37,000 men, I am aware that huge steps were taken to defend convoys but they were never halted, the principle used by Stalin was the same with the allies in some situations, especially cases like Malta.

 

[Geoffrey Sinclair]

American Merchant Marine Casualties says 9,521 dead, a 1 in 26 fatality rate, higher than any other US service.

The UK history Merchant shipping and the demands of war by Behrens notes some 25,862 "British" men were lost when their ships were attacked by the enemy, this includes civilian crews and the military personnel on board manning the guns. British is basically defined as crew on board the ships from the traditional sources of such men, Oriental sailors, Lascars, made up maybe 18% of the crews. Merchant sailors tended to sign on for a voyage, there was not the equivalent of a military personnel system tracking them when not at sea.

The above figures exclude men lost when the ship that rescued them was attacked or if the seamen were officially passengers. Then the total comes to around 26,833 merchant sailors. Then add the men lost to non direct combat causes, like marine accidents or friendly mines which raises the total to 31,908. However these figures exclude at least some men who were discharged because of their injuries and who subsequently died, effectively died of wounds, or who were "permanently damaged" to the point they could not obtain life insurance or would be insurable only under special terms. The history estimates of this number comes to around 8,000 for men discharged in 1943 and 1944. The history comes up with an estimated figure of 43,886 deaths or "permanent damage" from all causes when estimating the total lost to the end of 1944, then comes the 1945 deaths, about 317 direct deaths plus those ashore etc. So maybe 45,000 deaths and permanent damage, of which at least 32,000 were deaths. Or about half the total air raid casualties Britain took during the war. Like so many statistics it is what you count and when that determines the totals.

I understand that the machinery to cut the gears for steam turbine installations took a year to make. Similarly ships lost in 1939 meant 6 wartime years where they otherwise could have made voyages. Merchant ships did not become obsolete or worn out nearly as quickly as aircraft. Convoys cut shipping efficiency, military cargo cut shipping efficiency, military operations upped shipping requirements, the pre war fleets needed to be expanded.

In the period March to May 1944 weekly imports of oil products into the UK climbed to 402,000 tons, UK oil imports in 1938 had been an average of 223,000 tons per week, or over 9 million tons less per year. Given the round trip times in mid 1944 were of the order of 5 to 7 weeks you can see the size of the tanker fleet needed, then add the usual overheads for ships needing repairs.

"British" tanker losses to end November 1941 were around 2.1 million tons, balanced by under 3.1 million tons of gains, mostly the tanker fleets of countries the Germans had invaded. (850,000 tons was new construction.). So the fleet was around 4.2 million tons. The US non great lakes tanker fleet was 2.76 million tons in 1939, plus there was another 470,000 tons under the Panamanian flag. In the December 1941 to May 1942 period the allies lost 1.85 million tons of tankers, and another 750,000 June to August mainly off the US coast and in the Caribbean. Allied tanker tonnage went backwards to at least December 1942 and it took until the end of 1943 to get back to the end of 1941 position. After that the gains were more than a million tons per quarter more than the losses. Even so to help ease the shortage tankers were allowed out of convoy when crossing the Atlantic in 1944.

By destination in May 1944 the allied tanker fleet in Gross Register Tons, ships over 1,600 GRT, was distributed as follows,
2.2 million with the navies,
1.7 million under repair, refit etc.,
3.3 million supplying England, Iceland and the USSR,
1.4 million Western Mediterranean, Azores and West Africa,
2 million Pacific including the Vladivostok run,
2 million US and Canadian Eastern Seaboard,
2 million other Western Hemisphere,
1.8 million "Indian Ocean", including Libya, East and South Africa, India, Ceylon, Australia, New Zealand,
total 16.9 million

It was only the surrender of Germany in mid 1945 that saved the allies from having to decide which theatre to slow down because they did not have enough tanker capacity to service both. The Western Allies were hampered by merchant shipping all war and invasion shipping to around end 1944, the US decision to order large numbers of LST then cancel many of them in favour of DE then cancel many of the DE in favour of LST had a real cost.

Analysis of the Battle of the Atlantic faces the reality many things kept changing at the same time. More and better radars, direction finding, code breaking, sonar, anti submarine weapons and escorts all played their part, D/F on ships was tactically quite useful, more so if there was a fast escort present to send on a search. In the period July 1944 to end of war RN depth charge attack method success rate was 6.34%, Hedgehog 29.69%, Double Squid 40.74%, Squid 30%.

The wartime U-boat fleet hits its smallest size in April 1940, 49 down from 57 in August 1939, despite adding 15 new U-boats to the fleet. While many of the merchant ships sunk were neutrals. Then came the capture of French bases, the removal of the French navy and the need for Britain to maintain more light forces around Britain. Then the British were successful in evasive routing of convoys in the second half of 1941 thanks to cracking the U-boat Enigma. In the first half of 1941 the U-boats sank an average of around 500 tons per patrol day in the North Atlantic, down to 100 tons in the second half. However the increase in escorts, a reduction in ships sailing independently while increasing the minimum speed of any independent ships were the big reasons for lowering losses. Yet also add U-boats sent to the Mediterranean and Arctic reducing those available in the Atlantic.

Despite the classic convoy battle ideas the majority of sinkings were taking place outside convoys. According to the RN official history from January 1942 to May 1943 inclusive 537 ships were sunk in convoys (411 to subs), versus 1067 ships sailing independently (934 to subs). Even in the first 5 months of 1943 the convoys lost 193 ships versus 105 sailing independently.

The U-boat fleet changed its coding system at the end of 1941 which was probably fortunate for the allies, if the U-boats had stayed on the Atlantic routes the sudden increase in sightings would have been a good clue the old code had been read. The allies took until the end of 1942 to crack the new code (4th wheel).

Lloyd's War Losses
Percentage of total shipping sunk that was neutral shipping.
percentage of ships / percentage of GRT
1939 38.15 / 32.25
1940 20.00 / 16.99
1941 5.52 / 5.40
1942 5.24 / 3.51
1943 9.48 / 2.54
1944 13.08 / 2.22
1945 4.69 / 0.29
Grand 10.66 / 7.14

Cause of loss Submarines number / GRT, 2,755 / 14,392,398, mines 781 / 1,740,919, Aircraft 1,063 / 3,213,085, surface ship or raider 223 / 1,121,296, E-boat/MTB 118 / 263,916, scuttled 117 / 143,264, other 56 / 123,197 and unknown 298 / 316,573, Total 5,411 ships 21,314,648 GRT. Of this 577 ships 1,522,432 GRT were from neutral nations. Lloyd's reports a further 753 ships 1,416,185 GRT as captured. I am not sure of the lower tonnage limits for the Lloyd's figures, but as an example they include a ship of 17 tons.

As well Lloyds list another 387 ships of 951,078 GRT as unknown reasons for loss. Cross referencing Axis Submarine Successes by Jurgen Rohwer accounts for half of these and most of the tonnage. As well other ships have notes like "German radio claimed ship sunk by aircraft". Rohwer is clearly using the Lloyds list and he has different degrees of certainty when assigning the loss. From definite report with definite identification from the submarine to submarine and ship in same area, submarine did not come back to report. So there are some "ifs" in his assignments. I make the submarines could account for 194 of these ships, 746,783 GRT, so by far most of this tonnage was lost to war causes.

The RN calculated in 1942 that each U-boat sunk saved 4.8 merchant ships because it took the Germans 6 months to train a new U-boat crew. In the second half of 1942 long range anti submarine aircraft operations were calculated to save the following number of merchant ships per 100 sorties.
Continuous Convoy Escort, 3
Bombing U-boat bases, 1
Bay of Biscay patrols, 3
Escort of convoys known to be under attack, 30.

In WWII a general cargo ship estimated cost 7 or 8 units per ton, a large gun armed warship 100 and a U-boat 150, the economic ratio was about 5 merchant ships to the submarine. A lightly escorted convoy had little chance to sink U-boats, a heavily escorted one did. A convoy with 10 escorts was needed for an average break even economic loss, not counting cargoes, going from 10 to 14 escorts doubled the chances of sinking a U-boat, going to 18 escorts tripled it.

 

[RCAFson]

King surviving Paukenschlag may be evidence of divine intervention. His obstinance there cost many Allied lives, both at sea and on the other end of unfulfilled supply lines.

More likely, infernal intervention...

 

[RCAFson]

The minimal loses were 14,million tons and around 37,000 men, I am aware that huge steps were taken to defend convoys but they were never halted, the principle used by Stalin was the same with the allies in some situations, especially cases like Malta.

We have to separate MM ships sunk in convoy by U-boats vs ships sunk that were independently routed. The shipping losses during Drumbeat, and subsequent campaigns against the US coasts, for example, were almost entirely ships that were not in convoys.

This chapter discusses the value of Convoys:

HyperWar: Antisubmarine Warfare in World War II [Chapter 10]

 

[Ascent]

Something not mentioned yet, or at least I haven't seen it, is what capacity your industry has. If your factory can only turn out 250 units a month of whatever they're building, be it tanks or aircraft, then you want these 250 to be the best they can.

It would make no sense for the Germans to try and outproduce the Allies, the capacity simply wasn't there. Therefore it makes sense to make a tank like the Panther rather then the Sherman. Lot's of 'good enough' tanks was never a possibility, they needed to make a 'superior' product. Whether the Panther actually was a superior product is up for debate.

 

[Deleted member 68059]

Something not mentioned yet, or at least I haven't seen it, is what capacity your industry has. If your factory can only turn out 250 units a month of whatever they're building, be it tanks or aircraft, then you want these 250 to be the best they can.

It would make no sense for the Germans to try and outproduce the Allies, the capacity simply wasn't there. Therefore it makes sense to make a tank like the Panther rather then the Sherman. Lot's of 'good enough' tanks was never a possibility, they needed to make a 'superior' product. Whether the Panther actually was a superior product is up for debate.

You can also make a pretty convincing argument that lots of their "complicated" products were mostly hard to maintain and produce not so much due to the technology level, but due to very poor management of endless changes and having mind-bendingly vast numbers of sub-types. Even the "easy to make" 109 had a crazy number of sub-variants. All that can be put down to bad upper political project management in my opinion.

 

[z42]

Something not mentioned yet, or at least I haven't seen it, is what capacity your industry has. If your factory can only turn out 250 units a month of whatever they're building, be it tanks or aircraft, then you want these 250 to be the best they can.

It would make no sense for the Germans to try and outproduce the Allies, the capacity simply wasn't there. Therefore it makes sense to make a tank like the Panther rather then the Sherman. Lot's of 'good enough' tanks was never a possibility, they needed to make a 'superior' product. Whether the Panther actually was a superior product is up for debate.

Hmm, maybe. Though there are several issues with this

• Unlikely your factory can produce the same amount of 'best possible' widgets as 'meh, good enough' widgets. So how much more, and how much worse (and in which way worse?) needs to be taken into account.
• Just as the 7000 Panthers that they historically produced weren't enough to turn the war around, neither would a hypothetical 14000 'meh, good enough' tanks do in a hypothetical scenario. Or for that matter, 3500 King Tigers instead of the 7000 Panthers.
• One of the most successful German tank(ish) designs was the Stug III, which in essence was a cheap turretless version of the cheap and obsolete Pz III, and by virtue of omitting the turret was able to mount a high velocity 75mm cannon, good for anything on the battlefield except maybe the relatively rare heavy tanks. This allowed them to keep the Pz III production line running, and they churned out 10000 of these. So even the Germans were happy to use 'meh, good enough' equipment.

 

[z42]

You can also make a pretty convincing argument that lots of their "complicated" products were mostly hard to maintain and produce not so much due to the technology level, but due to very poor management of endless changes and having mind-bendingly vast numbers of sub-types. Even the "easy to make" 109 had a crazy number of sub-variants. All that can be put down to bad upper political project management in my opinion.

I read somewhere that for the Tiger I tank, on average 13 tanks were produced on the production line before some tweak or improvement was made. Good luck keeping up production rates with that approach, and not much thought spared to the poor sods who had to do field maintenance on those.

 

[Shortround6]

• Just as the 7000 Panthers that they historically produced weren't enough to turn the war around, neither would a hypothetical 14000 'meh, good enough' tanks do in a hypothetical scenario. Or for that matter, 3500 King Tigers instead of the 7000 Panthers.
• One of the most successful German tank(ish) designs was the Stug III, which in essence was a cheap turretless version of the cheap and obsolete Pz III, and by virtue of omitting the turret was able to mount a high velocity 75mm cannon, good for anything on the battlefield except maybe the relatively rare heavy tanks. This allowed them to keep the Pz III production line running, and they churned out 10000 of these. So even the Germans were happy to use 'meh, good enough' equipment.

The Germans can certainly be examples of what not to do. In some cases by being too ambitions and/or mucking up the "design" by trying to 'tweak' it part way through the process.
Germans were not the only countries to get caught by inflexible staff requirements (or Hitler requirements). Adding 5-10 tons to the design and keeping the original transmission seldom worked out for anybody no matter how much some of the extra weight added to protection. (See KVs and T-34s using the same engine/transmission)

The flip side is that you need a certain minimum number of "widgets". Best widgets in the world don't do much good if your opponents can just go around the widgets you do have.

Which brings us to the often mentioned Stug III, which was actually a pretty crappy tank. It was very good SP Anti-tank gun, it was not a tank. It was better than nothing for supporting infantry if the targets were not enemy tanks. But not by much. Which lead to things like this.

Which fired about the same HE shell and carried more of them and carried a lot more ammo for the machine gun/s. Note that the Stug had to mount the MG on the roof to engage infantry (or anything else). Also please note that 700 of the last MK III tanks built used the short 75mm gun (with around 20 more rounds) than the early Stug IIIs and carried over 5 times the amount of MG ammo (early Short Stugs didn't even have machine gun).

Stugs did very well on defense when the enemy delivered the targets to them, and the Stugs and German infantry could control (somewhat) the enemies approach.
They didn't work so well on the offensive or for dealing with things that didn't have large amounts of armor plate. Having to leave the battle and return to supply point for more ammo after the stug fired 15-20 rounds of HE/smoke and whatever none AP shells it had is a poor use of over 20 tons of vehicle. Solved in the early years (1940/41) by suppling armored ammunitions half tracks for every platoon/battery of Stugs. Which must have been cheaper than sticking the same guns on MK IV chassis and just carrying more ammo on the fighting vehicles.

Doesn't make as many subjects for todays modelers though

I read somewhere that for the Tiger I tank, on average 13 tanks were produced on the production line before some tweak or improvement was made. Good luck keeping up production rates with that approach, and not much thought spared to the poor sods who had to do field maintenance on those.

This problem is somewhat overstated by modern commentators. Yes there were a lot of changes, however moving the shovel brackets on tank number 333 and then moving the crowbar bracket on tank number 350 didn't really affect either production or field maintenance

 

[z42]

Which fired about the same HE shell and carried more of them and carried a lot more ammo for the machine gun/s. Note that the Stug had to mount the MG on the roof to engage infantry (or anything else). Also please note that 700 of the last MK III tanks built used the short 75mm gun (with around 20 more rounds) than the early Stug IIIs and carried over 5 times the amount of MG ammo (early Short Stugs didn't even have machine gun).

Stugs did very well on defense when the enemy delivered the targets to them, and the Stugs and German infantry could control (somewhat) the enemies approach.
They didn't work so well on the offensive or for dealing with things that didn't have large amounts of armor plate. Having to leave the battle and return to supply point for more ammo after the stug fired 15-20 rounds of HE/smoke and whatever none AP shells it had is a poor use of over 20 tons of vehicle. Solved in the early years (1940/41) by suppling armored ammunitions half tracks for every platoon/battery of Stugs. Which must have been cheaper than sticking the same guns on MK IV chassis and just carrying more ammo on the fighting vehicles.

Doesn't make as many subjects for todays modelers though

Yes, well, this was the days before the modern concept of the general purpose MBT. Everybody, not just the Germans, apparently strongly believed in the idea of one type of tank-like vehicle for each job. To the point that many vehicles with high-velocity AT guns never got decent HE shells, and thus were rather poor against softer targets.

At least fun for the modelers, as you say.

This problem is somewhat overstated by modern commentators. Yes there were a lot of changes, however moving the shovel brackets on tank number 333 and then moving the crowbar bracket on tank number 350 didn't really affect either production or field maintenance

Unfortunately I don't know the nature of these tweaks so can't comment on how much more difficult they generally made production or maintenance. Maybe some were as banal as welding some bracket in a slightly different spot, some were bigger changes?

 

[EwenS]

This problem is somewhat overstated by modern commentators. Yes there were a lot of changes, however moving the shovel brackets on tank number 333 and then moving the crowbar bracket on tank number 350 didn't really affect either production or field maintenance

Unfortunately I don't know the nature of these tweaks so can't comment on how much more difficult they generally made production or maintenance. Maybe some were as banal as welding some bracket in a slightly different spot, some were bigger changes?

To give some idea of what was being done see Osprey New Vanguard 5 "Tiger I Heavy Tank 1942-45"

"As with all series of German Panzers, modifications were frequently introduced during production runs. These modifications were prompted by a desire for improved automotive performance, increased forepower, additional protection, simplification of design for easierr manufacturing or in response to shortages."

Some of the visible changes made were

Aug 1942 - 3 smoke dischargers added each side of turret
Sept 1942 - removable mudguards bolted to hull sides to cover the wider cross-country tracks. Box for track adjusting tools mounted on rear hull (dicontinued in Nov 1943)
Oct 1942 - changes to tracks from vehicle 21. Instead of mirror image tracks left & right, rhs track used lhs reversed.
Nov 1942 - vehicles destined for tropical climes had air filters fitted at factory (lasted until Aug 1943)
Dec 1942 - escape hatch replace pistol port on turret from vehichle 50. Turret bin added from vehicle 56 (retrofitted to earlier production). Armour thickness on sides of gun mantle increased
Jan 1943 - heat guard fitted to exhausts to prevent glow in the dark. Drivers periscopes no longer fitted and apertures welded shut.
March 1943 - vehicle 179 onwards sheet metal shield added to protect commander from back-blast and flames from main gun breach. Vehicle 184 onwards turret periscope for loader fitted. Spare track links mounted on brackets on turret sides.
April 1943 - new internal seals and gears of final drive improved. Sprocket hub design improved.
May 1943 - new engine fitted with change to fan drives for improved cooling (vehicle 251 onwards)
June 1943 - smoke dischargers deleted from vehicle 286 as experience had seen them set off by small arms fire incapacitating the crew. New mounting bolts for the front shock absorbers (previous type had been working loose) from vehicle 301
July 1943 - vehicle 391 turret extensively redesigned. Only 1 headlight fitted instead of 2
Aug 1943 - deep fording components deleted to simplify production. Wading depth now limited to 1.5m
Sept 1943 - from vehicle 501 firewall redesigned to allow easier access to engine compartment. Zimmerit anti magnetic coating applied at factory
Nov 1943 - from vehicle 625, improved fan installed on fire wall to remove fumes from vehicle. From vehicle 635 (to 875 in Feb 1944) travel lock for 88mm gun fitted.
Dec 1943 - headlight location changed. tracks modified with 6 chevrons per link to improve traction on ice & snow)
Jan 1944 - from vehicle 762 suction pump & discharge pipe to remove water from tank deleted. From 772 mounting for jack modified to take 20t jack in place of 15t. Pistol port deleted. Hull side extension at front on both sides cut out to ease towing
Feb 1944 - Vehicle 822 steel roadwheels with internal rubber cushioning adopted from Tiger II. Vehicle 823 motor coolant heater added to preheat coolant before starting. Vehicle 850 turret ring guard added to prevent splinters jamming the turret. Vehicle 861 onwards 5 electrical components moved from engine bay to firewall in fighting compartment.
March 1944 - turret roof armour increased from 25mm to 40mm. Tiger II loaders hatch fitted
April 1944 - monocular instead of binocular telescope fitted (until appropriate new mantlet castings became available an armoured plug was welded in place). From vehicle 1075 wooden decking added to protect fuel tanks.
June 1944 - to ease maintenance 3 sockets welded to turret roof to anchor the base of a 2t jib boom (retrofitted to earlier vehicles)
Oct 1944 - internal ammo stowage increased by 16 rounds.

Production ceased in Aug 1944, having been tapering off since June in favour of Tiger II.

But Allied tank production was subject to production changes as well. A couple that come to mind are on the production run of 200 A30 Challengers were there were changes to the return sprockets as well extra armour being added leading to stronger shock absorbers being required.

Even something like the Sherman wasn't immune (leaving aside the different engines). Firefly conversions (on M4 & M4A4) depended on tanks selected for conversion having particular types of turret traverse mechanism. Depending on manufacturer & time of production there were varying types of roadwheel, sprockets, final drive casings, locations of lifting rings, ventilators, additional armour welded on or cast in and more notably different types of drivers hoods with and without direct vision ports, and with and without periscopes, changes to turret design (7 variations on the 75mm turrets) etc etc etc.

 

[Shortround6]

Yes, well, this was the days before the modern concept of the general purpose MBT. Everybody, not just the Germans, apparently strongly believed in the idea of one type of tank-like vehicle for each job. To the point that many vehicles with high-velocity AT guns never got decent HE shells, and thus were rather poor against softer targets.

Germans tended to over specialize. So did the British for a different reason, British wanted fast tanks and with the weight limits that meant thin armor (cruiser tank) and they wanted tanks that could accompany infantry and with the weight limits that meant thick armor and slow speed. At least they put them in different regiments (or planned to).

Germans mixed 3-4 different tanks in the same regiments and the Stugs went to different Divisions, not Panzer divisions, at least in 1940.
Stugs and Short MK IVs also had crap for AT rounds in 1940 (mostly) so the MK IVs with short barrels were supposed to provide HE and smoke support for the smaller panzers while the MK II and MK III did the anti-armor work and all three of the smaller tanks did the anti infantry/horse/truck soft target work. German short 7.5cm guns did start getting hollow charge shells in 1940 and more in 1941, also went through several different designs to get ones that worked on more than tin-can armor.
37mm tank guns (everybody's) were pretty lousy at soft target work, the shells go bang but were pretty anemic even compared to a hand grenade.
In 1939-41 the tanks did a lot of their work with machine guns and saved the cannon ammo for 'important' targets. The German MK IIs with 20mm guns originally only got AP for the 20mm gun.

Took a while for most armies to figure out that the enemy was not going to cooperate and only send the correct targets to suit the guns/tanks in the hands of the friendly troops.

But getting back the Germans in 1940, A MK IV carried 80 rounds of 7.5cm ammo and 2400-2700 rounds of MG ammo. Early Stug carried 44 rounds of 7.5cm ammo and 0000 rounds of MG ammo, no machine gun. Machine gun didn't show up until Sept 1941 (crews could scrounge one) but a crew man had to open a hatch, stick the gun through the hatch, stick head, shoulders and arms through the hatch and fire the MG over the roof, no mount. Bipod bouncing over the roof is not very stable. Tank gunner has power travers, gear wheel for elevation, is aiming with telescope, and is not as worried about an enemy sniper or rifleman shooting him as he makes a target of himself on top of SP gun.

A lot of stuff going on and some of the stuff that we have been told isn't as simple as it appears.
The Germans tried to do a lot of stuff on the cheap, least re-tooling of factories possible but sometimes getting stuff that just worked didn't really solve the problem long term and then you are stuck because you can't afford to shut down the factories to retool because you are chronically short of AFVs.

Having seen the T-34 in the summer of 1941 why did it take until Dec 1943 for this to show up?

And why did no PZ IV tank ever get a pointy nose or slightly sloped side armor?

Unfortunately I don't know the nature of these tweaks so can't comment on how much more difficult they generally made production or maintenance. Maybe some were as banal as welding some bracket in a slightly different spot, some were bigger changes?

The truth seems to be in-between, Yes there were a lot of changes on the Tiger that perhaps should have waited for 'batches' but it seems that the critics count every banal change to bolster their argument against it.
Please note that with the Spitfire Castle Bromwich was bitterly complaining about the changes coming from Supermarine in the spring/summer of 1940 in the 'production' drawings of the Spitfire making it very hard to tool up for mass production. Not the only instance on the allied side.

 

[Snautzer01]

And why did no PZ IV tank ever get a pointy nose or slightly sloped side armor?

Production is not speeded up with enourmous design changes. Its not peace time remember.
They needed all and more and fast. And more . Very much more.

 

[Shortround6]

Production is not speeded up with enourmous design changes. Its not peace time remember.
They needed all and more and fast. And more . Very much more.

True but they building the MK IV in three different factories, one of which was converted to build the Jagdpanzer IV with sloped armor to just about 1700 examples.
And they waited for just under a year after making the Panther tank.
The factory that built the Jagdpanzer was still building the square armored MK IV tank until May of 1944 so about a 5 month overlap until production of the tank finally stopped.
The drivetrain and the suspension and lower side armor, hull floor, rear hull and engine deck did not change.

after the Summer of 1944 only one factory continued to make the Panzer IV, the other had been converted to make the Stug IV with square armor.

The point is that sloped armor could have been used by a tank using existing mechanicals, Not as well perhaps as the Panther. But they wanted the big change and not incremental changes.

 

[GrauGeist]

Technically speaking, the Panther (PzKfw V) was supposed to replace the PzKfw IV.

 

[MIflyer]

So, to finalise, quality is the absolute #1 requirement above all else,

In space launch efforts that is true by at least an order of magnitude greater than for aviation, and aviation requires at least an order of magnitude greater than do ground vehicles. People who assert that aviation or space launch is in reality a lot easier than it is made out to be simply have not had a high speed 2X4 hit them in the head enough times to properly get their attention.

SpaceX scrubbed a Falcon Heavy launch last night in order to check some things out and tonight did the same thing. But when they started in the business they were the type to disparage such caution as being excessive. The legendary 2X4 taught them caution. Most of the people who marched into the space launch business confident that they would show the world how it should be done later crawled out with their tail between their legs; more than few should have been required to crawl into Ft Leavenworth.

 

[GrauGeist]

In space launch efforts that is true by at least an order of magnitude greater than for aviation, and aviation requires at least an order of magnitude greater than do ground vehicles. People who assert that aviation or space launch is in reality a lot easier than it is made out to be simply have not had a high speed 2X4 hit them in the head enough times to properly get their attention.

SpaceX scrubbed a Falcon Heavy launch last night in order to check some things out and tonight did the same thing. But when they started in the business they were the type to disparage such caution as being excessive. The legendary 2X4 taught them caution. Most of the people who marched into the space launch business confident that they would show the world how it should be done later crawled out with their tail between their legs; more than few should have been required to crawl into Ft Leavenworth.

This could also apply to deep-sea vehicle manufacturers/operators.

The ones that rush through a design, ignoring experienced input, don't last long.

 

[z42]

This could also apply to deep-sea vehicle manufacturers/operators.

The ones that rush through a design, ignoring experienced input, don't last long.

Crushing news to gung-ho yeeehaw entrepreneurs in that sector.

 

[z42]

Germans tended to over specialize. So did the British for a different reason, British wanted fast tanks and with the weight limits that meant thin armor (cruiser tank) and they wanted tanks that could accompany infantry and with the weight limits that meant thick armor and slow speed.

I suspect what was standing in the way of a 'universal' tank, or MBT at the outset of the war was doctrine as well as available guns. Engine-wise they could, had they so wished, been in a pretty decent position. Taking the British as an example, as you mentioned in another thread they could have used the RR Kestrel, which would have been powerful enough for the whole war. And if more power was needed, the Peregrine showed there was still some available headroom in the Kestrel design. And Kestrel was available from the late 1920'ies, so ample time to make a ruggedized and slightly de-rated version for tank usage.

But gun-wise, that's trickier. Most combatants started WWII with AT guns in the 40mm range (British 2-pounder, German 37mm, etc.). And for the thin-skinned tanks of the day that was enough. But for softer targets you wanted something shooting a bigger shell with more space for HE. So in a sense the separation between between the small caliber high velocity AT guns and low velocity large capacity guns for shooting HE made sense. Some efforts were made to combine both of these gun types in a single vehicle were made, like the M3 Grant, or the Churchill Mk I. Although perhaps not generally seen as particularly excellent concepts in retrospect. So in a way it was only when tank armor got heavier, and AT guns had to get bigger to compensate, that it started to make sense to have a single large caliber high velocity gun that could be used for both anti-tank and softer targets. But even after the technical pieces were starting to come together, it took a while for doctrine to catch up.