Delta Tank wrote: ↑29 Nov 2018, 14:27
Good information, thanks!! How many days of supply did they believe they needed on hand, 75 days? 90 days?
Mike
The assumption's for supply in the ETOUSA as of 1 June 1944 where all based upon a 75-day stockage versus anticipated usage. That is why the reserve of tanks was set at 75-days at anticipated wastage...and the same for items of equipment like BARs, mortars, items of consumables like ammunition, food, and even personnel. None of which worked as anticipated.
There were a couple of problems though. The 75-day turnaround time from cutting of a requisition to delivery at the front line actually proved to be more than 120 days. IIRC, the MTOUSA already complained about that, but ASF refused to change it until December 1944, when they agreed to a 135-day turnaround. The worse problem though was the wastage factors for equipment, consumables, and personnel were all based on figures derived from limited Great War data, guesstimates, and voodoo,,,at least insofar as I can tell. For some reason, 57mm HE was expected to be a significant round, so it was prioritized over the Pacific Theater, which received none until late 1944 while it was stockpiled in the ETO and virtually never used. Expenditure rates for artillery ammunition, especially 105mm, was set high, which led to over-stockage in North Africa, so the rates (and production allowances) were cut, leading to the "shortage" in Normandy as expenditures, the Great June Storm, and difficulties unloading over the beaches led to depot levels in Normandy falling below what was anticipated. That led First Army and then 12th Army Group to enact strict rationing so the stocks could be built up, which reduced the artillery's capabilities drastically during the fall and led to expedients such as using German and British weapons and ammunition. And yet, even in the extremity of the Battle of the Bulge when all rationing ceased, the levels never fell below a 21-30 day supply, which would have been a problem if the campaign continued for months more at that intensity, or if the U-Boats became a problem again, except...
In any case, trying to get wastage figures adjusted led to huge fights with ASF, which always argued the original figures were just fine and we don't need no stinkin' data showing us we're wrong...and yes, I exaggerate, a bit. For medium tanks, on 1 June the replacement factor was 7%, which was already LOWER than that experienced in North Africa (c. 7.6%), Sicily (9.6%), and the initial months in Italy (7.2%), partly I expect that because in the late fall and winter in Italy the rate fell to around 2%...gee, I wonder why? :roll: Amazingly though, by 15 June ASF agreed to adjust the rate to 9%...and then fought tooth and nail for ever increase over that no matter how many armor losses occurred. Bizarrely, they even argued that in calculating the "on hand" for the ETOUSA, tanks allotted, but not shipped from the factory, tanks on the docks waiting to load onto ships, tanks on board ships sailing to Europe, and tanks waiting to unload off the beaches all should be included, rather than the existing tanks with units and in theater reserve. By 13 August, the result was there were exactly 34 operational and 53 non-operational reserve tanks in theater and 2,084 were in the hands of the troops versus a TO&E requirement of 2,123, but it got worse. By 1 December, only 85.5% percent of tanks on hand versus TO&E were available and it dropped to just 77.0% by 1 January.
Personnel wastage and replacement rates were worse though, since the factors by combat branch and pseudo-branch were completely fudged given there was so little data for armor and AA artillery and none for tank destroyers in the Great War. So they initially assumed armor casualties would be much higher than they were, which led to overstocks in armor personnel, which were partly resolved by trained armor replacements being fed into battle assigned to armored infantry units...
:roll: AAA was even more extreme, since the initial personnel allotments were based on a huge number of units way in excess of what was ever required because of, well, the USAAF, which also sucked away huge numbers of personnel...and both the AAA and USAAF replacement factors were essentially fudges as well. So the infantry, which suffered the majority of wastage, got starved.