Glad to see You are back on track - are You back on Russian or German tracks 
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Saw a Army guy in the comments on Youtube complaining that the Marines got all the credits for Guadalcanal. So we should remember to switch to Army at the right moment.
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Haha. And off the tracks we go again. I doubt the army will ever say they got enough credit no matter how precise we are 
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should I put a warning in the question for any newcomer so that he/she doesn’t become confused about the thread suddenly changes tracks to octanes and then Guadalcanal ?
Unfortunately the option to edit the question is now missing, so a newcomer would have to be confused as to what is going on.
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I didn’t LST’s were a thing. I mostly thought those types of vessels (i didn’t know the name until now) was used for naval invasion crafts.
So did the US start mass producing this before even the start of the war to sell it to both the brits and french?
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I don’t think so … the idea of combat landing tanks on a hostile shore was pretty unlikely in the view of most military planners before 1940. The first LSTs were, I believe, conversions of existing ships to add bow doors and ramps and were less than 100% effective (as you’d imagine). By reputation, Winston Churchill was (again) instrumental in the early development of this ship type … although these were probably more of the “doodles on the back of a napkin” as Churchill for all his talents was not in any way a naval architect.
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LST: You can read the full story here:
https://en.wikipedia.org/wiki/Landing_Ship,_Tank
If you search on Google on “lst omaha beach” you can see pictures of LSTs in action on Omaha Beach.
According to my readning the beaching concept was developed during operations, much to the anger of the captains in the beginning. But it proved very effective.
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This is actually a pretty significant change in loading. In 1942, a ship’s loading was optimized for keeping heavy cargo as low in the ship as possible and maximizing the use of the cubic cargo space available. At the other end of its journey, the ship would be unloaded at dockside by longshoremen using cranes, nets, and other cargo-handling equipment. For the time, this was the most efficient way to get the best use out of a cargo ship’s capacity.
On the other hand, a cargo ship had to be loaded very differently for landing equipment in a combat zone (potentially under enemy fire). The last items to be loaded had to be the equipment and supplies that the fighting troops needed first, so that the pace of the invasion could be maintained. They had to be unloaded in the combat zone without external cranes by the ship’s company augmented by whatever manpower the ground commander could spare. A properly combat-loaded ship was incredibly inefficient by normal loading standards and carried far less total cargo so no shipping authority ever combat-loaded until an invasion was imminent and the ship was already near the combat area.
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Excellent information. Thanks
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Greg has just put up another great topic on German “Uber Octane” which destroys a lot of myths made by the whereaboos. Also Germans had to stick to the physics. If you hate the techie details just watch the intro and the conclusions 
He also has a very nice advert for the Bischmark who oddly has an aviation channel.
German C3 Fuel, Uber Octane or Synthetic Crap? - YouTube
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I saw that the other day, but the length kind of kept me away- but thanks for posting. Now that I saw the beginning, turns out that I know him. Not for real, but virtually. Because of the first half of my user name, lol.
But one other comment about synthetic fuels- it’s a lot easier to make small HC molecules, and even easier to make oxygenated versions of the same (alcohol has been made for centuries), and all of those simple HC’s have really high octane ratings. I agree that the super high octane “closed loop” HC’s are pretty hard, though.
I’ve gotten through 25 min of the video, and plan on finishing it later. So until I finish, I won’t comment on my thoughts, as I expect him to cover them later. (based on how he’s presenting the first part) (FWIW, I’m an automotive engineer, working with how engines run (specifically emissions) for just about 30 years (retirement soon!!!)).
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Hey that is really cool, you know a lot. I am just a pilot who flew warbirds and more or less got into engines because of that. Gregg really offers a lot of stuff allowing me to understand it and apply the knowledge.
His vids are really long (by todays standards) that is why I recommended to watch the intro and conclusion. I also learned at Uni to read history books that way 1 intro 2 conclusions and then the middle part to verify how the writer came to those conclusions. In my experience this works well but that is just my 2 cents
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So you are very aware of the air density effect, which has an effect on how well something can be boosted.
I’m looking forward to learning how the planes controlled boost, which I expect to be constant absolute manifold pressure instead of relative pressure. Which would make sense as he got to his effective compression calculation.
Fun tangent on the rail line question, but it’s so much about energy resource allocation for the Germans.
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Yeah, not being aware killed many pilots. In Santa Fe New Mexico (Jet Warbird school) the planes sometimes can’t fly in hot weather because of high density altitude. In simple turns it is the altitude the plane feels it is and you notice immediately.
I must admit I didn’t know anything about it until flight school but once I got into it and learned the basics it became fascinating. The more I learn the more I realize that there is a lot more to learn and things get more complicated. 
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Finished watching it- and while Greg didn’t talk about boost control- I think they were controlling to an absolute limit instead of relative limit.
But, one thing he did point out was that the German synthetic fuel was of pretty darned high octane fuel. Considerably higher, even running lean, compared to oil based fuel they were using.
What I found pretty interesting though, was the idea that the German engines were not using the full capability of the fuel they were making. I never knew that, and the given theory seems very likely. But it also has an interesting counter- why didn’t the Germans work on the engine designs to run hotter to not deal with the lack of evaporation from the oil? Doing that would have been hard, but also worth it- probably gained at least 100hp on their motors just running them hotter.
But that just adds to the very numerous questions that start “why didn’t the Germans…”
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Unfortunately your arguments aren’t supported by events. Where were the food riots in Petrograd 1942?
The Germans did occupy the Don coal fields, but the Russians had the Siberian coal fields.
And the US sent several million tonnes of refined fuel to the USSR.
The Germans (expecting to stay in Russia permenently) were changing the Russian “wide gauge” to “standard gauge” rail lines as they went along. Especially in 1941, this process was well behind the lines; the German offensives moved very much faster than rail rip-up-and-lay-our-guage operations.
With the ‘correct’ rail gauge, the germans could use all their existing (and pilfered from anybody else) engines and rolling stock. The Russians had a disturbing habit of taking their trains with them when they retreated, so to use “wide gauge” would have required the Germans to build not only “standard” but also “wide” engines and freight cars. (And do that unload/load operation you talk about.)
As the Russian/German war continued, the Russians, when they started rolling the Germans back, had to change the rail lines back. This is one of the reasons the Russians had an attack-pause-attack offensive behavior – they had to rebuild their supply net on the fly. (The Germans, being better at improvisation, could be less affected by outrunning the rail net.)
Hope this helps!
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So… How does one change the guage without the rail rip-up?
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In theory you can just move a rail, but generally its safer to put down a new one (with steel you know the quality of.) If you’re in a hurry, or short on rails, you will have to use version #1 with captured rails (presuming the Russians didn’t have time to bend them into pleasing shapes - a tactic used as far back as the American Civil War.). But I should have been more specific, thanks for pointing it out! (And reading it at all
Reading up for this, I found that both the Germans and the Russians had specialized machines to destroy rail lines (the German one having a suitably German name, the “Schwellenpflug”) These machines were intended to destroy the ‘bed’ – the carefully leveled, and able to stand the weight of trains going back and forth – ground of the rail line.
The Russians rail troop formations were “Railway Brigades”; the Germans “Eisenbahnpioniere” – whose task to destroy rail lines, depots, bridges and tunnels ahead of advancing badguys, and build 'em going the other way.
There, now aren’t you sorry you asked?
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Nope… I am willing throw away my honour for knowledge. (Since, you were joking in the last line… I am returning the favour).
So was soviet steel different from German Steel in terms of quality?
How does one bend a rail? Hit it till it changes shape?
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