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Taking them apart, transporting them, reworking them was labor intensive.
The 25mm Hotchkiss AA gun was not very good anyway. Park them in France, give them away, don't spend any more German resources on them.
Time/money spent on modifying 25mm ATG barrels to fit 25mm AA guns is time/money not spent of new barrels/guns for 2cm Flak 38s or 3.7cm Flak 37s
It was trade off, the French 25mm fired about 2/3 the number of shells per minute. and that is counting magazine changes.The 25mm AA gun fired the twice as heavy shell than the 2cm Flak did, at the same velocity.
An awful lot depends on sights and mounting. I am rather suspicious of a lot of these light AA ranges. For a 3000m range for a gun with a 900m/s velocity that means a flight time of 3.3 seconds, not counting air resistance. Now how many of these light AA guns had sights that allowed for aiming even 3 seconds ahead of an aircraft? even a biplane flying 180kph moves 50 meters in one second. A 300kph plane moves 83meters per second.Means it will ought to outrage the light Flak that Germans had in scores (= 1-barreled 2cm), and that seems to be so, 3000m vs. 2000m for the 2cm (terms and conditions apply). It will also have a better ceiling.
It was trade off, the French 25mm fired about 2/3 the number of shells per minute. and that is counting magazine changes.
An awful lot depends on sights and mounting. I am rather suspicious of a lot of these light AA ranges. For a 3000m range for a gun with a 900m/s velocity that means a flight time of 3.3 seconds, not counting air resistance. Now how many of these light AA guns had sights that allowed for aiming even 3 seconds ahead of an aircraft? even a biplane flying 180kph moves 50 meters in one second. A 300kph plane moves 83meters per second.
Considering the rather dismal performance of the 25mm gun in Japanese service (unknown in 1940) it would seem that devoting any energy/money to any program involving the 25mm Hotchkiss AA gun would only benefit the Allies.
Romanians were buying German stuff, like the He 112, already in 1939, and were pushed even more towards Germany by the Summer of 1940.The Romanian time line is also skewed a little. Romania doesn't join the Axis until Nov 23 1940, at which point the Germans had moved around 500,000 troops into Romania in the last 6 weeks. Romanian relations with both Germany and Russia are somewhat twisted. Germany agreed for the Soviets to take back large areas of Romania when the Soviets 'occupied' eastern Poland. Then got Romania to help Germany in return for German help in regaining the lost territory. Germany isn't shipping much of anything to Romania until Dec of 1940?
Am I missing something piece of history? The British oil industry never had steam trucks and the railways were in private ownership. I am guessing that English is not your first language? The British steam lorries fell out of use in the 1930s because people were not buying them. Economics not government policy.in those early 1930s, the British oil industry (and the government because of the railways) decided to get rid of steam trucks.
A French, Belgian, Czech, Polish, Yugoslav and Ukrainian man will much more likely be working in the mines than it will be serving as a soldier fighting for the German cause.When one thinks of coal as a widely available resource for both Britain and Germany one has to consider manpower. Men fit to be miners are ideal soldier material. Germany used POWs and forced foreign labour to keep their mines going and still could not meet demand even with mines in conquered countries. The British were forced to send 10% of their conscripts into the mines instead of the armed forces and still fell short of demand. They maintained this even when desperately short of infantry in 1944/5. The extra manpower and supply of extra (good) coal for a German army relying upon steam powered lorries might simply not have been available. Also the greater bulk of coal for the same energy as liquid fuel places extra pressure upon the already overloaded rail and road system. Any transshipment breaks with coal needs more labour than liquid fuels too.
Very little 115/145 was produced during the war. See my previous postOne could argue that with lower octane gas than the Allies (C3 was what, roughly equivalent to 100/130, whereas late in the war R-2800 ran on 115/145?), and poorer valves, bearings etc., the Germans could get away with slightly more volume per cylinder before running into cooling limits due to the surface area vs volume issues you described.
Not disputing that. Just saying that having less volume per cylinder could have been an advantage for the USAAF while remaining irrelevant for the LW due to the fuel situation. Now whether that was foreseen back when the engines were designed is another matter entirely.Very little 115/145 was produced during the war.
No it's not.I am guessing that English is not your first language?
When one thinks of coal as a widely available resource for both Britain and Germany one has to consider manpower. Men fit to be miners are ideal soldier material. Germany used POWs and forced foreign labour to keep their mines going and still could not meet demand even with mines in conquered countries.
The subject has to be assessed at a system level not just a technical level.
My conclusion on the steam lorry question is that they would be better than horses. A useful supplement to liquid fuelled ones lorries but in the period rail was still king and the best place to spend your coal. The caveat is that it needs a huge investment in preparing for the necessary massive civil engineering program to be able to do it across Russia at a speed to meet the need. It would eat up all the army bunker building concrete and naval steel production of to mention forestry for a start.
Is that a worse situation than having petrol-fueled trucks?Steam wagons would be competing for a restricted resource that would be better used elsewhere
But it wasn't an advantage in reality so your point is moot.Not disputing that. Just saying that having less volume per cylinder could have been an advantage for the USAAF while remaining irrelevant for the LW due to the fuel situation. Now whether that was foreseen back when the engines were designed is another matter entirely.
More importantly is it any better.Is that a worse situation than having petrol-fueled trucks?
More importantly is it any better.
The Northern Pacific 2-8-8-4 Yellowstones also burned Rosebud and to do so had the largest firebox ever. https://www.steamlocomotive.com/locobase.php?country=USA&wheel=2-8-8-4&railroad=npJust for reference in the US in 2022 there were 4 different types of coal.
From https://www.eia.gov/energyexplained/coal/
Anthracite contains 86%–97% carbon and generally has the highest heating value of all ranks of coal. Anthracite accounted for less than 1% of the coal mined in the United States in 2022. All anthracite mines in the United States are in northeastern Pennsylvania.
Bituminous coal contains 45%–86% carbon. Bituminous coal is the most abundant rank of coal found in the United States, and it accounted for about 46% of total U.S. coal production in 2022. Bituminous coal is used to generate electricity and is an important fuel and raw material for making coking coal for the iron and steel industry. Bituminous coal was produced in at least 16 states in 2022, but five states accounted for about 78% of total bituminous production. The top five bituminous producing states and their percentage share of total U.S. bituminous production in 2022 were:
Subbituminous coal typically contains 35%–45% carbon, and it has a lower heating value than bituminous coal. In 2022, subbituminous coal accounted for about 46% of total U.S. coal production. The five subbituminous producing states and their percentage share of total U.S. subbituminous production in 2022 were:
- West Virginia—31%
- Illinois—14%
- Pennsylvania—14%
- Kentucky—11%
- Indiana—9%
Lignite contains 25%–35% carbon and has the lowest energy content of all coal ranks. Lignite is crumbly and has high moisture content, which contributes to its low heating value. In 2022, five states produced lignite, which accounted for 8% of total U.S. coal production. The five lignite-producing states and their percentage share of total U.S. lignite production in 2022 were:
- Wyoming—89%
- Montana—8%
- New Mexico—2%
- Colorado—2%
- Alaska—<1%
Note the lack of cross over of types of coal from region to region. Also note the huge difference between high grade Bituminous and low grade Bituminous You might need around 50-60% more tons of low grade Bituminous than you do high grade, even cutting off the extremes.
- North Dakota—56%
- Texas—36%
- Mississippi—7%
- Louisiana—1%
- Montana—<1%
Yes you can design fire boxes and boilers to use different types of coal. But to run well they have to use a somewhat consistent type of coal. BTW in many older books/magazines some US Railroads than were using engines running on subbituminous were described as burning lignite.
View attachment 813842
Northern Pacific was one RR that burned low grade fuel (Subbituminous/lignite) using a rather large fire box/grate. Apparently true lignite is rather crumbly and needs a bigger firebox/grate area, closer spaced grate rods and smaller inlet air hole in the bottom. Larger/standard airholes tend to blow the smaller coal pieces up out of the fire box, through the boiler tubes and out the stack. True lignite was mostly used in stationary power plants.
"Like all NP Northerns, the A-2s burned Rosebud coal, a fuel with 22-28% moisture content and 7-9% percent ash. Compared to more typical locomotive coal, which were rated at 11,000-15,000 BTU/pound, Rosebud generated 8,750 BTU. Such low-grade brown stuff was laid by a Standard modified type B stoker on a large grate. Firebox heating surface area included 62.6 sq ft " This is for the class right after the one in the photo. The stoker was a mechanical stoker to move the quantity of fuel per hour than these big locomotives needed.
Granted a much small boiler could be hand fired.
Low grade fuels (solid or liquid) should be used in rear areas were it is easy to replenish fuel due to short trips. Using low grade fuel for moving long distance can mean doubling the amount (tonnage) of fuel used for long distance traveled which means less cargo actually moved (might be only 1-2 coal wagons per trip?).