Switching production -- How long might that take?

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kitplane01

Airman 1st Class
135
32
Apr 23, 2020
Lets suppose that Italy some time in 1938-1942 looks at it's fighters and decides they mostly suck. Further, they get permission from Germany to make (say) Me 109's and the associated engines. How much production might Italy lose by making this decision? Six month, a year, what do you think?

Lets suppose that some time in 1942-1944 the US looks at it's P-40 factories and decides this is not what we need any more. The decide to build (choose-a-fighter) instead. How much production might the US lose by making this decision? Six month, a year, what do you think?

Let assume it's done in an intelligent way. We don't shut down the old production until the last possible moment. We'll get organized, build tooling, inform our supply chain, etc. first. Then switch production in a reasonable and intelligent way.

And in general, is it harder to switch an engine factory or an aircraft factory?
 
Italy's industry and logistics were quite weak during that time. I think Italy's most produced fighter was the Cr.42, and they only made 1,819. If they were to switch to the 109 in 1941 or 42 then it would be easier than if they switched in 1938-40 imo. This is because Italy's C.202 fighter used a license-built DB601 and was starting production in 1941. It would still take a long time to switch production. Germany also had a habit of giving almost the least assistance possible to their allies. I don't know that much about how long it took factories to retool during the war, but taking into account that it took the Soviets roughly a year to move their IL-2 factories past the Urals and get them working, I think it would take about 8 months.
 
Lets suppose that Italy some time in 1938-1942 looks at it's fighters and decides they mostly suck. Further, they get permission from Germany to make (say) Me 109's and the associated engines. How much production might Italy lose by making this decision? Six month, a year, what do you think?

Lets suppose that some time in 1942-1944 the US looks at it's P-40 factories and decides this is not what we need any more. The decide to build (choose-a-fighter) instead. How much production might the US lose by making this decision? Six month, a year, what do you think?

Let assume it's done in an intelligent way. We don't shut down the old production until the last possible moment. We'll get organized, build tooling, inform our supply chain, etc. first. Then switch production in a reasonable and intelligent way.

The quoted passage is perhaps better fitting for our 'What if' sub-forum.

And in general, is it harder to switch an engine factory or an aircraft factory?

IMO - it was harder for engine factory to make a switch, unless the engine types have a lot in common.
 
It took almost exactly two years for the Castle Bromwich factory to start making Spitfires but some time to ramp up production. It took just over a year for the RR factory in Glasgow to produce an engine with production increasing to about 200 month after another 8 months and 400 month after another 9 months. . However these were British factories building British designs. I don't know if there would be language and standards issues building a German design in Italy in the 1930s. As Fastmongrel said an issue is manpower, the RR Glasgow factory produced most of the merlin "in house" and employed 16,000 people.
 
Hey kitplane01,

I really cannot speak to the WWII situation. But I worked on the alternate diesel power plant project for the M1 Abrams back in the early-1980s. The engine was a detail-improved evolution of the then standard AVDS-1790 used in the M60 series of tanks. Even though most of the production equipment would have been the same (about 80%) and the skill set for production pretty much exactly the same, it was estimated that it would take about 6 months from start of switch-over to the first real production engine being accepted by the US Army. Most of the delay would have been due to the change in materials (abut 30% different) supply chain and in the changeover to the new part specifications (about 50% different), followed by the inspection and acceptance testing/certification. This was in peacetime and the push for the engine was never at what it might be in a wartime situation, but there was pressure for immediate production if it was decided to use the diesel rather than the turbine. The project managers (including the production engineers) indicated that it would be impossible to switch over any sooner and have any real chance of quality control.
 
Hey kitplane01,

I really cannot speak to the WWII situation. But I worked on the alternate diesel power plant project for the M1 Abrams back in the early-1980s. The engine was a detail-improved evolution of the then standard AVDS-1790 used in the M60 series of tanks. Even though most of the production equipment would have been the same (about 80%) and the skill set for production pretty much exactly the same, it was estimated that it would take about 6 months from start of switch-over to the first real production engine being accepted by the US Army. Most of the delay would have been due to the change in materials (abut 30% different) supply chain and in the changeover to the new part specifications (about 50% different), followed by the inspection and acceptance testing/certification. This was in peacetime and the push for the engine was never at what it might be in a wartime situation, but there was pressure for immediate production if it was decided to use the diesel rather than the turbine. The project managers (including the production engineers) indicated that it would be impossible to switch over any sooner and have any real chance of quality control.

Was this the multi-fuel engine with variable compression?
Or am I thinking of another engine?
 
It took almost exactly two years for the Castle Bromwich factory to start making Spitfires but some time to ramp up production. It took just over a year for the RR factory in Glasgow to produce an engine with production increasing to about 200 month after another 8 months and 400 month after another 9 months. . However these were British factories building British designs. I don't know if there would be language and standards issues building a German design in Italy in the 1930s. As Fastmongrel said an issue is manpower, the RR Glasgow factory produced most of the merlin "in house" and employed 16,000 people.


I thought the Russians could move a factory across the Urals and get it working again in a year??? Conditions had to be better in the UK than Russia. I wonder if there was significant resource constraints. Also, I wonder if Russian leadership is more "forceful".
 
Define working??

get a couple of planes a week or a couple of planes per day, every day.
Russians, due in part to the forcing, were often good at meeting target numbers while sacrificing fit and finish (or even hammering steel bolts through wooden spars/ribs) and using 99-100% of components for finished aircraft leaving none to be sent to the front as spares which lead to higher than normal unserviceability, which in turn sometimes meant a call for higher production.

As for how fast a factory could convert over. The Grumman Factory may be one of the better examples, It took them from the beginning of Dec 1942 until the end of July 1943 to build the first 500 F6F Hellcats. They reached the 1000nd F6F less than 2 months later and were soon building 400-500 a month by winter of 1944.
Eastern Aircraft had taken over all production of the F4F and TBF leaving Grumman free to work on the F6F but I have no idea if they were still adding workers and floor space (or adding subcontractors) in 1943.
No factory managed to convert from one type to another in a seamless, minor drop in production fashion.
In fact even changing from one sub type/variant to another could result in drop in production. Depends on how many differences there were. Some P-39s changed letters just by changing the prop. On some planes changing the wing armament (number of guns and ammo boxes and all accessories and hatches) called for hundreds of engineering changes and drawings. Not to mention the actual differences in putting the actual parts of that section of wing together.
Workers often found shortcuts or devised special tools. My father had worked at Sikorsky in the early 40s and then at Chance Vought building F4Us until his deferment ran out and he joined the Marines. In the 1950s his roll around tool box in the garage still had a few open end or box end wrenches that had been cut off to fit in confined spaces and a few that had been cut to little more than the jaws (or box) with a piece of steel rod welded to them at 90 degrees to really get into a small space to keep something from turning. Torque would be applied to the other side/end of the bolt. Workers have to learn what tools or combination of tools work best in certain areas or in what order certain parts/bolts/fasteners need to be installed to do the job the fastest. In some cases a few bolts might be installed loosely to hold a part in place while another part is installed or so they are already in place when the new part might block good access. Once learned this type of thing can be passed from worker to worker or even written down in instructions but when you are dealing with a new airplane even the engineers don't always know the best way to actually put all the pieces together.
 
Also, I wonder if Russian leadership is more "forceful".

Russian leadership was indeed more forceful. Here's a famous quote from Stalin about one factory's IL-2 Sturmovik production:
"You have let down our country and our Red Army. You have the nerve not to manufacture IL-2s until now. Our Red Army now needs IL-2 aircraft like the air it breathes, like the bread it eats. Shenkman produces one IL-2 a day and Tretyakov builds one or two MiG-3s daily. It is a mockery of our country and the Red Army. I ask you not to try the government's patience, and demand that you manufacture more ILs. This is my final warning.
  • Telegram to government aviation production plant superintendents by Stalin in the autumn of 1941, warning them to produce more Il-2 Sturmovik ground attack aircraft for national defense." (From Wikiquotes Joseph Stalin - Wikiquote)
Also, from the other replies on this thread, I'm now thinking it may have taken longer for the Italians to switch production in that situation. I suppose there are a lot of factors that contribute to stuff like this
 
I thought the Russians could move a factory across the Urals and get it working again in a year??? Conditions had to be better in the UK than Russia. I wonder if there was significant resource constraints. Also, I wonder if Russian leadership is more "forceful".
Moving a factory but then using the same tooling, workforce, engineers and parts would be much easier than starting from scratch.

Perhaps a better example would be the Canadians tooling up to build Lancasters, using US built Packard Merlins. As I recall, there was considerable time and some quality control issues compared to British factories
 
Hey gjs238,

At the time I left the project in 1983 it was only using diesel. We had cleared the engine for 1200 HP, and were just beginning the next phase with 1400 HP as the target. However, JP-8 and diesel are similar enough in behavior that variable compression is not required, and subsequent variants of the AVDS-1790 were cleared as dual fuel engines (with minor detail modifications).

It is probable that you are thinking of the AVCR-1360, which was designed with variable compression from the start, using a "hydraulic piston".

see: "US3450111A - Variable compression ratio piston assembly - Google Patents"

The AVCR-1360 was the official alternative to the turbine during the XM1 tank competition between GM and Chrysler, and (in theory at least) was more developed (it was already generating 1400 HP) than the AVDS-1790 we were working on. Unfortunately it was having serious development & reliability issues, almost as bad as the turbine in the early days. Hence the project I worked on. There was a later attempt to apply the same 'hydraulic piston' to the AVCR-1790, but that was after my time, and I heard that it did not go well.

The overall engineering and production mods for a M1/AVDS-1790 variant would probably have delayed introduction of the M1 into service by 2+ years. The reduced purchase/operating cost and potential increased reliability/maintainability of the AVDS-1790 variant were not considered worth the delay, particularly in view of the not yet achieved 25:1 HP:weight ratio (1500 HP for 60 tons) originally specified by the DOD. Eventually the really serious problems with the turbine were worked out, after ~2 years (ie in 1983) and ~$100,000,000 of turbine engine wastage.:banghead:
 
I thought the Russians could move a factory across the Urals and get it working again in a year??? Conditions had to be better in the UK than Russia. I wonder if there was significant resource constraints. Also, I wonder if Russian leadership is more "forceful".
Possibly, but that was after the Russians were invaded by a bunch of fanatics who were killing for the fun of it. The OP was about building a new factory not moving a factory which is a different proposition. For the factory at Glasgow not only did almost everyone have to be trained from scratch but houses built for workers too.
 
Moving a factory but then using the same tooling, workforce, engineers and parts would be much easier than starting from scratch.

Perhaps a better example would be the Canadians tooling up to build Lancasters, using US built Packard Merlins. As I recall, there was considerable time and some quality control issues compared to British factories
To be fair to people in Canada the factory that first produced Lancasters in UK had already made 202 Manchesters and many other aircraft before that.
 
-Somewhat related to this is the reluctance of the governing body to make changes.
-I can't remember the specifics but wasn't there some issue with the P-38 where Lockheed wanted to shut down production for a couple of weeks to change the line over to a much improved version but the AAF said no?
 
Lets suppose that Italy some time in 1938-1942 looks at it's fighters and decides they mostly suck. Further, they get permission from Germany to make (say) Me 109's and the associated engines. How much production might Italy lose by making this decision? Six month, a year, what do you think?

Lets suppose that some time in 1942-1944 the US looks at it's P-40 factories and decides this is not what we need any more. The decide to build (choose-a-fighter) instead. How much production might the US lose by making this decision? Six month, a year, what do you think?

Let assume it's done in an intelligent way. We don't shut down the old production until the last possible moment. We'll get organized, build tooling, inform our supply chain, etc. first. Then switch production in a reasonable and intelligent way.

And in general, is it harder to switch an engine factory or an aircraft factory?

IIRC both the P51 and Lancaster were sold on the basis that in the time needed to retool to become second-source suppliers of the P40 and Halifax respectively they could develop a new, better aircraft. I think something similar happened with Consolidated and the B24.
 
don't know that much about how long it took factories to retool during the war, but taking into account that it took the Soviets roughly a year to move their IL-2 factories past the Urals and get them working,

Yes and no.
Factories, in general, were relocated not only past the Urals but also "before the Urals" as in Kuibyshev, for example. About 15,000 of Il-2 were produced by one factory which was situated in Voronezh, then relocated to Kuibyshev and returned back to Voronezh.
From three main manufacturers of Il-2, only one was located beyond the Urals in Irkutsk.
Overall, in the USSR in WWII there were various examples of more and less successful relocations. If we take Kuibyshev - production has begun in about a month after the relocation. The rate was very slow, of course, and it took several months to normalize everything. Another example - factories in Molotov began to produce Su-2 as fast as in Kuibyshev, but then by the decision of GKO, Su-2 was slaughtered in favor of Il-2 and Il-4. Ironically, further production was delayed by various reasons and eventually canceled and the factories were re-profiled for other work.
 
General Motors signed a contract to build Wildcats and Avengers at the end of January, 1942. They had to strip out the car plants in New Jersey of auto machine tool's, modify the buildings for aircraft production and retrain their workers in the art of aircraft production. They had to source all their own suppliers so as to not hinder Grumman's own production. The first Wildcat and Avenger started coming off the assembly lines in August of 1942. There is a book called The History of Eastern Aircraft that tells of that undertaking.
 

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