You continue to insist on a fantasy world in which there's only one route to Turkey from Europe.Peter89 wrote:The whole idea is fundamentally flawed, because to get through with the supplies to Turkey, the Germans could only use one, limited-capacity (14t/axle, about 40km/h, maximum about 12 trains/d) railway.
We've already discussed the Aegean route; your argument that it doesn't work is based on "one time some German ships hit mines." That logjam is apparently - like Ithaka's gulf - impervious to being cleared. So moving on...
Aegean aside, your argument might have some strictly logical sense if we pretend Germany had zero shipping available in the Black Sea. That's empirically - and obviously - nonsense. I've already mentioned the existence of the Kriegrstransport, many of which were built in Black Sea basin and operated there. That incontrovertible fact alone should dispel the fantasy of Turkey as some unreachable island beyond the Black Sea (you're living in Greece- maybe Strabo's view of Pontas Axeinos as wild and barbarian still prevails there?).
But I guess we need more proof that crossing the Black Sea was possible for Germany. Fine:
Here's what Kroneuburg Shipyard on the Danube built OTL during the war:
6 type N motor tugs, 7 type R motor tugs, 8 Black Sea standard ships type SME, 3 war transport ships type KT, 8 marine ferry boats type MFP, 34 loading flaps for MFP, 60 1,000-t tank barges, 12 1,000-t barges... http://othes.univie.ac.at/1919/1/2008-10-01_9806698.pdf This isn't the only shipyard on the Danube obviously...
Germany also built >200 Siebel Ferries OTL, any of which could be moved by rail to the Danube, thence to Black Sea. Siebel's could carry 169t at ~6kn.
Germany also had 100 MFP's in the Black Sea OTL; each carried 140t at ~10kn.
Germany also had 16 R-Boats, 23 S-Boats, and 26 subchasers in the Black Sea OTL. Yes these are warships but with no fighting in the Black Sea they can used to ferry troops/equipment. Most likely they'd be used to pull some of the dozens of 1,000t barges available to Germany in the Black Sea OTL if motor tugs are lacking.
Wait there's more! Romania and Bulgaria also border the Black Sea and they too had ships! Who would have thought? For Romania alone I count 25 ships that could tow barges, only 5 of which lost during the war (surely some lost after ATL's 1942 peace). https://en.wikipedia.org/wiki/Romanian_ ... rld_War_II Romania also had a lot of barges and coastal shipping but I'm not even going to start counting them yet to bolster my analysis. Bulgaria had at least 11 ships of sufficient size to tow large barges (e.g. torpedo boats). https://en.wikipedia.org/wiki/Black_Sea ... 2%80%9344) (citations in article).
Notice how I keep saying "OTL?" Why is that?
Because anyone who thinks Germany wouldn't build more cheap shipping (e.g. Siebel ferries and towable barges) if doing so were required to conquer the Middle East is living in a fantasy of German blindness. Germany could have quite rapidly built up its improvised Black Sea shipping fleet. Indeed it certainly would have done so in anticipation of Caucasus oil and Donbas coal needing to be shipped by 1943. In the meantime the nascent trade fleet could have been used to move German troops across the Black Sea.
From where would they embark and where unload? Humoring the idea that Germany couldn't improve Balkan rail connections for now, let's pretend they all embark from Black Sea ports like Varna, Burgas, Constanta, Odessa, and Sevastopol. I hope it's obvious that there is no conceivable argument that Germany couldn't have moved supplies for 20 divisions on the rail lines leading to these ports: Germany moved supplies for 180 divisions on these same rail lines during Barbarossa.
Ok so now we have supplies for 10 inf. and 10 panzer divisions in Black Sea ports - 4,500 t/day. Can our OTL Black Sea Fleet move it? Absolutely. First, let's remember to look at DISTANCE when doing logistical analysis. The Black Sea ports are all ~200nm from Zonguldak, which connects to Turkey's heaviest railway:

The distance to Istanbul's Anatolian rail terminus is obviously far less. From Sevastopol to Samsun - terminus of another heavy Turkish railway - is ~270 nm. Let's call the average Trans-Black haul 200nm.
Now let's estimate roundtrip sailing times by ship type, add a day (for Siebels and MFP's) or two (larger ships) for loading/unloading, and calculate each type's monthly Trans-Black capacity per hull.
Round trip steaming times:
- Siebel ferry at 7kn: 2.38 days RT sailing, 3.38 days turnaround time (TRT), 169t/trip = 1,500 t/month.
- MFP at 9kn: 1.89 days sailing, 2.89 days TRT, 140t/trip = 1,453/month
- 1,000t barge towed at 4kn: 4.17 days sailing, 6.17 days TRT, 1,000t/trip = 4,862 t/month.
With 200 Siebel's and 50 barges we're close to 700k t/month in Trans-Black shipping.
...and I forgot to include the Kriegtransports.
...and we haven't considered that ATL conditions would warrant additional shipping investment if needed. Nor have we considered Romania/Bulgaria/Hungary and their merchant fleets.
The extra shipping capacity gives us room to work with if, say, the partisans destroy ALL railroads in the Balkans, forcing Germany to ship from Odessa or Mikolaev, which are ~twice as far from Turkey. It also allows us to send shipments via the Aegean to ease northern Turkey's burden if necessary (assuming the invincible British sub spotted around Ithaka doesn't enter the Straits).
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Finally - and I can't believe it's come to this - let's join Peter89's fantasy about a Black Sea on which no Axis merchant ship can sail. In that world, there's a technically feasible (and appropriately silly) solution: rail shipment around the Black Sea.
OTL Germany supported ~180 divisions in 1942 (inc. Allies) on rail LoC's stretching at least 1,000km on average (depending on where average cargo originates, much farther. Ruhr-Stalingrad is >2,500km by air). From Berlin to the Turkish-Armenian border and its rail connection is ~2,700km by rail. So in terms of German rail rolling-stock assets, it would cost ~3x as much to support a division in Armenia as on the OTL Eastern Front. Supporting 20 divisions through Armenia would require 1/3rd of the Ostheer's OTL rail logistics burden.
In this silly world where German ships can't cross the Black Sea, can Germany devote 1/3rd of its OTL Barbarossa rail logistics to 20 divisions in Armenia?
Yes, of course - there's no other Ostheer combat going on.
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In sum, a little numerical logistical analysis - always preferable to unquantified generalities - shows that Germany would have no problem getting supplies for 20 divisions to Turkey. It is a fantasy to pretend otherwise, one that must rely on sea monsters and omnipotent barbarians lurking in the deeps and forests.