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>>This is by any measure not a big concentration of ships, armor, or anything. D-day landings were impressive in 1944 but today these won't be big at all. The

>>This is by any measure not a big concentration of ships, armor, or anything. D-day landings were impressive in 1944 but today these won't be big at all. The US pushed ~28,000 tons of supplies ashore in the first 5 days of Overlord. Eight days later it had grown to 117,000 tons. [1] Can you show us your loading and sealift plan for delivering 10,000 tons per day of supplies, sustained, in a partially-contested airspace, especially over a beach? We're not talking about unloading a Maersk Triple E-class [2] at a container port in peacetime. [1] https://en.wikipedia.org/wiki/American_logistics_in_the_Normandy_campaign https://en.wikipedia.org/wiki/American_logistics_in_the_Norm... [2] https://en.wikipedia.org/wiki/Triple_E-class_container_ship https://en.wikipedia.org/wiki/Triple_E-class_container_ship

anovikov 2y ago
Over such a short distance as back then? Well, i'm sure San Antonio class amphibious transport docks will be an overkill, but each can carry up to 14 tanks that are, today, over 70 tons heavy (in general, a 25K ton displacement ship can carry a lot of stuff easily). These alone will be easily enough to bring all necessary personnel, supplies, and heavy vehicles (light vehicles being much more numerous, could be problematic). As for assorted supplies without too heavy or bulky separate items, 10K tons per day is a joke and can be shuffled by helicopters alone. Remember distances were absurdly short, 120-150km, easily within helicopter range, and they can make several sorties per day at this short range. Over time, pilot fatigue will become an issue and accident rate might get bit too high, but for combat operations this isn't a big deal because there will be higher losses to enemy fire.
- CapricornNoble 2y ago
  EDIT: Made a major mistake in my numbers. Reworked the calculations but the substantive part of the argument remains the same. A San Antonio has ~20,000 square feet of deck space usable for vehicles and cargo. If you stuffed it with TEUs you could fit 125.[0][1] Maximum mass capacity for a TEU is ~21t, let's call it 20t for easy math.[2] So a San Antonio moving containerized beans/bullets/bandaids is only lifting ~2,500 tons per sortie. There are only 12 active San Anontios, and keep in mind roughly 1/3 of any fleet is down for maintenance), so you would need half of all likely available LPDs (4 of 8 available with 4 in yardwork) of the largest (by tonnage, not hull numbers) Navy on the planet. As for helicopters, you can carry palletized cargo internally on a CH-53 (one of it's few advantages over a CH-47). The K model, with stronger engines (and therefore payload capacity) than the E model, can move ~12t at 200km.[3] Let's just call it 10t at 200km, again for easy math. You would need 1,000 sorties in a day to move 10kt. If you pushed your aircraft to 3 sorties per day (limited by ground crew ability to turn the aircraft), you could do it with ~333 heavy lift helicopters. The US only has ~20 operational CH-53Ks, and ~140 CH-53Es. So no, moving 10kt per day is not a joke, and can't be shuffled by helicopters alone. It would take both asset classes combined, let's call it 3xLPD for 7.5kt and ~80 CH-53s flying 240 sorties for 2.4kt. That would pretty much be a maximum effort for the Navy-Marine Corps Team, which is inarguably the largest and most capable military power projection and expeditionary logistics force on Earth. So even in 2024, what they accomplished on D-Day is not a trivial amount of effort. [0] https://www.navsea.navy.mil/Home/Team-Ships/PEO-Ships/LPD-17/ https://www.navsea.navy.mil/Home/Team-Ships/PEO-Ships/LPD-17... [1] 20000 / (20ft long x 8ft wide TEU) ~= 125 TEUs worth of deck space, assuming you use ALL deckspace but can't/don't stack them 2 high [2] https://en.wikipedia.org/wiki/Twenty-foot_equivalent_unit https://en.wikipedia.org/wiki/Twenty-foot_equivalent_unit [3] https://www.navair.navy.mil/product/CH-53K-King-Stallion https://www.navair.navy.mil/product/CH-53K-King-Stallion

anovikov 2y ago

Over such a short distance as back then? Well, i'm sure San Antonio class amphibious transport docks will be an overkill, but each can carry up to 14 tanks that are, today, over 70 tons heavy (in general, a 25K ton displacement ship can carry a lot of stuff easily). These alone will be easily enough to bring all necessary personnel, supplies, and heavy vehicles (light vehicles being much more numerous, could be problematic). As for assorted supplies without too heavy or bulky separate items, 10K tons per day is a joke and can be shuffled by helicopters alone. Remember distances were absurdly short, 120-150km, easily within helicopter range, and they can make several sorties per day at this short range. Over time, pilot fatigue will become an issue and accident rate might get bit too high, but for combat operations this isn't a big deal because there will be higher losses to enemy fire.

CapricornNoble 2y ago
EDIT: Made a major mistake in my numbers. Reworked the calculations but the substantive part of the argument remains the same. A San Antonio has ~20,000 square feet of deck space usable for vehicles and cargo. If you stuffed it with TEUs you could fit 125.[0][1] Maximum mass capacity for a TEU is ~21t, let's call it 20t for easy math.[2] So a San Antonio moving containerized beans/bullets/bandaids is only lifting ~2,500 tons per sortie. There are only 12 active San Anontios, and keep in mind roughly 1/3 of any fleet is down for maintenance), so you would need half of all likely available LPDs (4 of 8 available with 4 in yardwork) of the largest (by tonnage, not hull numbers) Navy on the planet. As for helicopters, you can carry palletized cargo internally on a CH-53 (one of it's few advantages over a CH-47). The K model, with stronger engines (and therefore payload capacity) than the E model, can move ~12t at 200km.[3] Let's just call it 10t at 200km, again for easy math. You would need 1,000 sorties in a day to move 10kt. If you pushed your aircraft to 3 sorties per day (limited by ground crew ability to turn the aircraft), you could do it with ~333 heavy lift helicopters. The US only has ~20 operational CH-53Ks, and ~140 CH-53Es. So no, moving 10kt per day is not a joke, and can't be shuffled by helicopters alone. It would take both asset classes combined, let's call it 3xLPD for 7.5kt and ~80 CH-53s flying 240 sorties for 2.4kt. That would pretty much be a maximum effort for the Navy-Marine Corps Team, which is inarguably the largest and most capable military power projection and expeditionary logistics force on Earth. So even in 2024, what they accomplished on D-Day is not a trivial amount of effort. [0] https://www.navsea.navy.mil/Home/Team-Ships/PEO-Ships/LPD-17/ https://www.navsea.navy.mil/Home/Team-Ships/PEO-Ships/LPD-17... [1] 20000 / (20ft long x 8ft wide TEU) ~= 125 TEUs worth of deck space, assuming you use ALL deckspace but can't/don't stack them 2 high [2] https://en.wikipedia.org/wiki/Twenty-foot_equivalent_unit https://en.wikipedia.org/wiki/Twenty-foot_equivalent_unit [3] https://www.navair.navy.mil/product/CH-53K-King-Stallion https://www.navair.navy.mil/product/CH-53K-King-Stallion