How Sealion could have been made workable?

DA,

Your conjecture sounds VERY sensible to me, and I can add but one point. With the Wehrmacht decimated (hate that word) in France, would an invasion of France been 'do-able' in 1942 or 43?


John.

 

I don't know. My expertise is really in the Pacific Theater and I haven't studied Normandy in any great detail. I think one of the Allied problems in 1942 was a lack of logistical shipping necessary to support a large scale invasion. By 1943, that may have been largely remedied, but I haven't researched that specific issue.

BTW, I came across the following list of RN ships in home waters and elsewhere as of September 16, 1940. I thought you might be interested: it makes a mockery of the idea that the Germans could even think of controlling the Channel approaches.

The Royal Navy: Order of battle, 16 September 1940
Source: "Pink List" for 16th September 1940, Operations Division, Admiralty Naval Staff (Public Record Office ADM187/9).

Vessels under repair or refitting are marked *;

Minesweeping destroyers marked (†).

Abreviations:
RN: Royal Navy; RCN: Royal Canadian Navy; RAN: Royal Australian Navy; NZD: New Zealand Division; RIN: Royal Indian Navy; PO: Polish Navy; NO: Royal Norwegian Navy; NL: Royal Netherlands Navy; FFNL: Free French Naval Force; BS: Battle Squadron; BCS: Battle Cruiser Squadron; CS: Cruiser Squadron; AAS: Anti-Aircraft Squadron; DF: Destroyer Flotilla; SMF: Submarine Flotilla; A/SSF: Anti-submarine striking force; M/LS: Minelaying squadron; M/SF: Minesweeping Flotilla; MTBF: Motor torpedo-boat flotilla; MA/SBF: Motor anti-submarine boat flotilla; F: Flagship; C-in-C: Flagship of the Commander in Chief; RA(D): flagship of rear admiral commanding destroyers; F, VA: Flagship of vice-admiral commanding a squadron; F, RA: Flag of rear-admiral second-in-command of a squadron.


HOME FLEET (ADM CL Forbes)
2nd BS: Nelson (C-in-C), Rodney, Barham
BCS (VADM WJ Whitworth): Hood(F), Repulse (RA(D))
Aircraft Carriers: Furious, Argus
1st CS (VADM JHD Cunningham): Devonshire (F), Australia (RAN), Berwick, Norfolk, Sussex*, Suffolk*
2nd CS (VADM ATB Curteis): Galatea (F), Aurora, Cardiff
15th CS (RADM ELS King): Naiad (F), Bonadventure
18th CS (VADM LE Holland, RADM EN Syfret): Manchester(VA), Southampton(RA), Birmingham, Glasgow, Edinburgh*, Fiji*
1st M/LS (RADM WF Wake-Walker): Southern Prince, Menestheus, Port Napier, Port Quebec, Agamemnon
1st M/SF: Bramble, Britomart, Hazard, Hebe, Speedy, Seagull*
Destroyers (RA(D) RHC Hallifax)
3rd DF (Capt P Todd): Inglefield, Duncan, Echo, Eclipse, Electra, Escapade, Isis
4th DF (Capt PL Vian): Cossack, Maori, Sikh, Zulu, Fame*, Fearless*, Foxhound*
6th DF (Capt C Caslon): Somali, Ashanti, Matabele, Tartar, Bedouin, Punjabi, Eskimo, Mashona*
12th DF: Keppel, Achates, Amazon, Arrow, Active, Antelope, Douglas, Ambuscade*, Anthony*
23rd Div: Cattistock, Eglington, Holderness, Quorn
Submarines (VADM Sir Max Horton)
2nd SMF (Capt GCP Menzies): Taku, Talisman, Tigris, Tribune, Tuna, Cachalot, Porpoise, Trident*, Triumph*
3rd SMF (Capt P Ruck-Keene): Seawolf, Snapper, Sunfish, H 49, Wilk (PO), Sealion*
6th SMF (Cdr JS Bethell): Sturgeon, Swordfish, Ursula, Utmost
7th SMF (under VADM(S)): Otway, Upright, H.31, H.32, H.33, H.34, H.44, H.50, O.9(NL), B.1(NO), Oberon*, H.28*, O.10*(NL)
9th SMF: Clyde, L.23, L.26, O.21(NL), O.22(NL), O.23(NL), O.24(NL), Rubis(FFNL), Severn*
Northern Patrol:
AMC: Cilicia, Circassia, Forfar, Laurentic, Letitia, Patroclus, Wolfe, Worcestershire
WesternPatrol:
AMC: California, Cheshire, Chitral, Derbyshire, Salopian

ROSYTH COMMAND (VADM CG Ramsey, ashore at Rosyth)
Rosyth Escort Force:
AA Destroyers: Valorous, Vanity, Vega, Verdun, Viceroy, Vimiera, Vivien, Wallace, Westminster, Winchester, Wolfhound, Wolsey, Woolston
Sloops: Black Swan, Egret, Fleetwood, Hastings, Londonderry, Lowestoft, Stork, Weston
Torpedo Boats: Z.5 (NL), Z.6 (NL), Z.7 (NL), Z.8 (NL)

NORE COMMAND (ADM Hon RAR Plunkett-Ernle-Erle-Drax, ashore at Chatham)
Cruisers: London*, Arethusa*
Unattached Sloops: Gruno (NL), Flores (NL), Lupin (civilian crew), Kittiwake*, Pelican*
2nd MA/SBF: MA/SB.6, MA/SB.8, MA/SB.9, MA/SB.10, MA/SB.11, MA/SB.7*
Humber:
1st AAS (RADM JGP Vivian): Cairo (F), Curacoa
5th DF (Capt Lord Mountbatten): Javelin, Jaguar, Jupiter, Jackal, Kashmir, Kipling, Kelvin, Jersey*, Kelly*
Harwich:
16th DF (Capt TE Halsey): Malcolm, Watchman, Vortigern
18th DF (under Capt D 16): Worcester, Wivern, Verity, Veteran, Wild Swan, Venomous, Montrose*, Whitshed*
1st A/SSF: Mallard, Pintail, Puffin, Sheldrake
2nd A/SSF: Guillemot, Shearwater, Widgeon
1st MTBF: MTB.14, MTB.15, MTB.16, MTB.17, MTB.18
4th MTBF: MTB.22, MTB.29, MTB.24, MTB.25, MTB.28, MTB.30, MTB.31, MTB.32, MTB.33, MTB.34
10th MTBF: MTB.67, MTB.104, MTB.106, MTB.107, MTB.68
Nore:
20th DF (Capt RH Bickford): Icarus, Impulsive, Express*, Intrepid*
21st DF (Capt CTM Pizey): Campbell, Vesper, Vivacious, Walpole, Versatile, Vanessa*, Vimy, Venetia, Hambledon, Garth, Windsor*

DOVER COMMAND (VADM BH Ramsay, ashore at Dover)
11th MTBF: MTB.69, MTB.70, MTB.71*, MTB.72, MTB.5, MTB.6

PORTSMOUTH COMMAND (ADM Sir William James, ashore at Portsmouth):
Battleship: Queen Elizabeth*
Monitors: Marshal Soult*, Erebus
Cruisers: Penelope*, Heemskerck* (NL);
Seaplane Tender: Pegasus
Unassigned destroyers: Boadicea*, Viceroy*
Unassigned sloop: Bideford*
1st DF (Capt GE Creasy): Berkeley, Fernie, Brilliant, Beagle, Bulldog, Atherstone*, Acheron*, Boreas*
9th DF (Capt EBK Stevens): Havelock, Highlander, Harvester, Hesperus, Hurricane, Wolverine, Volunteer, Vanoc, Viscount
22nd DF (under Capt D 1): Sabre, Shikari, Sturdy, Skate, Scimitar, Saladin, Sardonyx
23rd DF: Branlebas, L'Incomprise, La Cordeliere, La Flore, Bouclier(NL), La Melpomene(FFNL)
5th SMF (Training): H.43, L.27
3rd MTBF (training): MTB.102*, MTB.100*
Unassigned MTBs: MTB.19*, MTB.3, MTB.4
1st MA/SBF (Portland): MA/SB.1, MA/SB.4, MA/SB.5
4th MA/SBF (Fowey): MA/SB.52, MA/SB.54, MA/SB.55, MA/SB.56, MA/SB.57, MA/SB.58, MA/SB.53, MA/SB.59, MA/SB.60
Unassigned MA/SB: MA/SB.12, MA/SB.41, MA/SB.48, MA/SB.49, MA/SB.13, MA/SB.14, MA/SB.40

WESTERN APPROACHES COMMAND (Admiral M Dunbar-Nasmith, ashore at Plymouth)
Battleships: Revenge, Centurion*(disarmed)
Cruisers: Emerald, Sheffield, Newcastle, Frobisher*, Exeter*, Belfast*, Adventure*
11th DF (Liverpool): MacKay, Winchelsea, Warwick, Walker, Westcott, Vanquisher
17th DF (Plymouth): Broke, Witherington, Witch, Wanderer, Vansittart, Whitehall
Polish Destroyers (Plymouth): Blyskawica (PO), Burza (PO), Ouragan (FFNL), Garland (PO)
Unassigned Corvettes: Asphodel, Fleur de Lys, Honeysuckle, Heliotrope;
3rd MA/SBF: MA/SB.42, MA/SB.43, MA/SB.44, MA/SB.45, MA/SB.46, MA/SB.47, MA/SB.50, MA/SB.51

Northern Escort Force (Rosyth):
Destroyers: St Laurent (RCN), Skeena (RCN), Restigouche (RCN), Margaree (RCN)
Sloops: Fowey, Gleaner, Jason, Leith, Rochester, Sandwich, Aberdeen*,
Corvettes: Bluebell, Camelia, Clematis, Gardenia, Hibiscus, Peony, Primrose, Primula, Campanula

Liverpool Escort Force (Liverpool):
Liverpool Sloop Division: Deptford, Enchantress, Folkestone, Scarborough, Wellington
Liverpool Corvette Division: Anemone, Arabis, Calendula, Clarkia, Coreopsis, Erica, Geranium, Gladiolus, Gloxinia, Heartsease, Mallow, Periwinkle, Picottee

FORCE H (Gibraltar) (VADM JF Somerville)
Battleship: Resolution
Battlecruiser: Renown (F)
Aircraft Carrier: Ark Royal
8th DF: Faulknor, Fortune, Fury, Forester, Foresight, Firedrake

North Atlantic Command (VADM Dudley North, ashore at Gibraltar)
13th DF: Greyhound, Gallant, Griffin, Encounter, Hotspur, Vidette, Velox, Wishart, Wrestler

Dispositions of Warships in Home Waters, 1600hrs/16 September 1940 with approximate steaming times to Dungeness (in the center of the invasion area). Minesweeping destroyers marked †

Scapa Flow (26 hrs from Dungeness at 20kts)
1 BC: Repulse (RA(D)), 1 BM: Erebus
1 CV: Furious (12 Skua, 18 Swordfish, 6 Gladiator)
2 CA: Berwick, Norfolk
1 CL: Glasgow, 1 CLAA: Curacoa
6 DD: Somali (D6), Eskimo, Matabele, Duncan, Versatile, Vimy
1 DE: Eglington; 1 SS: L.23
Dundee (19 hrs)
3 TB: Z.5 (NL), Z.6 (NL), Z.8 (NL)
3 SS: L.26, O.21 (NL), O.24 (NL)
Rosyth (18hrs)
2 BB: Nelson (C-in-C), Rodney
1 BC: Hood (VA, BCS)
3 CLAA: Naiad (RA, CS15), Bonadventure, Cairo (RA, AAS)
13 DD: Cossack (D4), Maori, Sikh, Zulu, Jackal†, Kashmir†, Kipling†, Ashanti, Bedouin, Punjabi, Tartar, Electra†, Vortigern
4 DE: Valorous, Vega†, Verdun†, Woolston
1 TB: Sleipner (NO)
2 SS: Seawolf, Snapper,
Blyth (14 hrs)
3 SS: Sturgeon, Swordfish, Ursula
Humber (10 hrs)
3 CL: Manchester (VA, CS18), Southampton (RA, CS18), Birmingham
5 DD: Javelin† (D5), Jupiter†, Jaguar†, Kelvin†, Watchman
Lowestoft (5 hrs): 1 TB: Draug (NO), 1 MTB: MTB.18
Harwich (3 5 hrs)
6 DD: Malcolm (D16), Venomous, Verity, Wild Swan, Wivern, Worcester
1 SS: H 44
11 MTB: MTB.14, MTB.15, MTB.16, MTB.17, MTB.22, MTB.28, MTB.29, MTB.31, MTB.32, MTB.34, MTB.67, MTB.68
London (4 5 hrs) 1 MTB: MTB.24
Sheerness/Chatham (4 hrs)
2 CL: Galatea (VA, CS2), Aurora
8 DD: Brilliant, Icarus†, Impulsive†, Campbell (D21), Venetia, Vesper, Vivacious, Walpole
10 DE: Cattistock, Holderness, Garth, Hambledon, Vanity, Vimiera†, Wallace, Westminster, Winchester, Wolsey
Dover (1 hr) 2 MTB: MTB.6, MTB.72

Portsmouth (3 5 hrs)
1 CL: Cardiff
12 DD: Beagle, Bulldog, Havelock (D9), Harvester, Hesperus, Highlander, Vanoc, Viscount, Saladin, Sardonyx, Sturdy, Mistral
2 DE: Berkeley, Fernie
5 TB: Branlebas, L'Incomprise, La Cordeliere, La Flore, Z 7
2 SS: Ondine, Orion
6 MTB: MTB.3, MTB.4, MTB.5, MTB.25, MTB.30, MTB.33
Southampton (4 hrs) 2 DD: Volunteer, Wolverine
Portland (5 hrs) 2 MTB: MTB.69, MTB.70
Plymouth (8 hrs)
1 BB: Revenge
2 CL: Newcastle, Emerald
11 DD: Isis†, Broke, Vansittart, Whitehall, Westcott, Blyskawica (PO), Burza (PO), Ouragan (FFNL), Garland† (PO)
3 TB: Bouclier(NL), La Melpomene (FFNL),
Milford Haven (14 hrs) 1 TB: G.13 (NL)
Liverpool (18 5hrs)
3 DD: Vanquisher, Walker, Sabre
Firth of Clyde (21 5 hrs)
1 CL: Sheffield
10 DD: Keppel (D12), Achates†, Active†, Amazon†, Antelope†, Arrow†, Douglas, Ottawa (RCN), Skeena† (RCN), St Laurent† (RCN)
6 SS: Tigris, Otway, Upright, B.1 (NO), H.31, H.34
Oban/Tobermory (22 5 hrs)
3 SS: H.32, H.33, H.50
Belfast/Londonderry (20 hrs)
3 DD: Shikari, Scimitar, Skate

Destroyers at Sea (patrols, escorting convoys etc )
8 DD: Veteran (left Harwich 17 Sep), Witherington (left Plymouth 16 Sep), MacKay (left Plymouth 15 Sep), Hurricane (left Liverpool 15 Sep), Winchelsea (left Liverpool 13 Sep), Warwick (left Liverpool 11 Sep), Witch (left Belfast 17 Sep), Wanderer (left Londonderry 16 Sep)
2 DE: Vivien (left Rosyth 16 Sep), Wolfhound (left Rosyth 15 Sep),
1 TB: G.15 (NL) (left Plymouth 16 Sep)

Submarines on patrol
17 SS: H.49, H.43, L.27, Clyde, Sunfish, Tuna, Taku, Talisman, Tribune, Cachalot, Porpoise, Utmost, O.9 (NL), O.22 (NL), O.23 (NL), Rubis (FFNL), Wilk (PO)

Dispositon of British Warships in the North Atlantic
Halifax
3 DD: Restigouche† (RCN), Assiniboine (RCN), Saguenay (RCN)
Gibraltar
1 BC: Renown (VA, Force "H")
8 DD: Gallant†, Griffin†, Encounter†, Hotspur†, Vidette, Velox, Wishart, Wrestler
Freetown (Force M, for Dakar landings)
2 BB: Barham, Resolution
2 CV: Ark Royal (24 Skua, 30 Swordfish), Argus (no aircarft)
3 CA: Devonshire (VA, CS1), Australia (RAN), Cornwall
11 DD: Inglefield (D3), Echo†, Eclipse†, Escapade†, Faulknor (D8), Firedrake†, Foresight†, Forester†, Fortune†, Fury†, Greyhound†
Lagos: 1 CL: Dragon
Bermuda: 1 CL: Dunedin
Tortola: 1 CL: Caradoc
At Sea
1 CA Cumberland
3 CL: Enterprise, Delhi, Despatch
1 SS: O.14 (NL)

 

I disagree. The Luftwaffe has too many other tasks to perform to throw massive numbers of dive bombers (which, in any case, they do not have) at the RN. It took TEN days for the Luftwaffe to sink just nine ships at Crete, they are not likely to do any better in a cross-Channel invasion where the battle would effectively be over in 24-48 hours. The bulk of the RN losses at Crete were incurred in an evacuation where the ships had to remain stationary, or nearly so, even when under air attack; that would not be the case in a Channel battle. In any case, the RN would accept the losses to prevent an invasion of Britain. Your point about a more effective U-boat campaign is well-taken, but if the RN suffered excessive losses, the US would undoubtedly move to take up the slack, so it's benefit to Germany's war effort is highly doubtful.

 

Every problem calls for a solution. Bodyboards!


P.S. or boards for the bodies...

 

Not so. Remember WWI hadn't been all that long ago. In any case the Wehrmacht wasn't going to be doing anything it had much experience with either. With minimal armored and artillery support and little logistics this wasn't going to be blitzkrieg. At least with the Germans doing the blitzing.

 

The Germans planned to have at least a third of the barges powered from what I've read. Indeed the powered barges were suppose to tow some of the unpowered ones. The one test I've read about seams to have been conducted with all powered barges. It was deemed a success. I think they had about 50 barges in the test and were only at sea for a couble of hours. One barge swamped (the soldiers rushed to one side because it looked like they might collide with another barge). A significant number of the barges ended up beaching side on so that it would have been difficult to unload them and almost impossible to get them off the beach. More details are on the web (I'll try and find some urls if no one posts them first). Oh yes it was a bright sunny day with minimal winds from what I remember reading.

 

I disagree, You can look at the speed at which the Germans took France and I think that explains it all. The British lacked the armour to effectively counter the Germans, and although the Germans themselves were new to war, they had been training for it and were relatively ready for a war. There combined arms doctrines were in place and every section involved whether it be the tanks in the front, th einfantry pulling up the rear, or the Luftwaffe providing close ground support, they were using the blitzkrieg tactic to its full and this is evident in the success of the campaign.

Although ww1 was 30 odd years ago in terms of ww2, many of the soldiers were new to war and the military, it was the younger generation that was fighting this war not the soldiers from the Great war, of course there are exceptions.
since after all "It is old men that declare war and it is the young men who fight them"

 

I believe it was one panzersiffe and 3 light cruisers all of which were assigned to various decoy missions no where near the invasion site.

Planned is the right word. They didn't even have enough mines to come anywhere near building the barriers called for in the plan. Even if they did they lacked the mine layers to do so in a timely fashion. And many of the minelayers they did have needed to be used as mine sweepers and invasion escorts all at the same time. The Uboats operating in the shallow waters near the invasion beaches and routes would have solved a lot of Britains ASW problems for some time.

 

In Sealion the Germans would have had minimal armor. For that matter minimal trucks or even horses and been pretty low on artillery as well. I think one of the Canadian divisions in Britain was an armored division.

The doctrine may have been in place but it's hard to impliment without the equipment. The LW could have got there but they were tasked with enough things to keep a force several times there size busy without the RAF or British AA taking a hand.

Well acording to the math I learned in shool its 20 years betwen 1919 and 1939 so make that 22 years between WW I and Sea Lion to be generous.

But it's the senior NCOs and mid level officers that are critical and they would have been the ones with experiance. Not to mention a lot of the home guard.

Sometimes but that's irrelevant to what we are discussing.

 

Good point.

Anther good point, but the Germans would never had let there landing forces to go in without proper support from the air, it is like letting your child out in the rain without an umbrella.

You are right, I was hasty with my working out, I went 1910 - 1940 = 30 years.

WEll you could have the most experienced officer in the world, but that is not going to be enough to stop a tank, you need the weapons and the properly trained men to take it out with minimal loss, it is not a few that win wars but many.

.[/quote]

Not sometimes, all the time. The point was that the older men from ww1 most probably had already moved on to other areas, whether up in the military or politics, such as Churchill. The bulk of the men would be young men, not older ones. Also, even had the older and experienced ww1 men made up the bulk of the army, they were not experienced in fast flying close ground support planes or modern tanks for that matter, this was a new and different war.

 

Then how do you account for say Alexander the Great? He was hardly and old man and that refutes your claim.

More later when I have time.

 

"Old men declare war. But it is the youth that must fight and die. "
Herbert Hoover

It is not my quote but Herbert Hoover and since I do not know much about Alexander there appear to exceptions.

 

Please don't bring Megas Alexander to the fray. You're talking about a time that has nothing to do with ours. He was the king he declared wars. Nowadays, things don't work like that. The Macedonian NCOs were also quite experienced and the Hypaspist corps had an average age of 40. Still, different society different time different rules. And still Alexander was more of the exception than the Rule don't you think??



Cheers...

 

Alexander (later A. III) commanded his first cavalry charge in battle at the ripe age of 17.

Once you've "seen the elephant", then you've seen most of them, so you'll be unlikely to sh!t in your pants and turn tail when you see one for the first time. The root for the word "veteran" comes from the Latin "veteris", "old man". Again, Huzzah for the old pharts!

 

DA,

Your #79.


I have been searching for just that data for yonks, and never succeeded.

THANK YOU!


John.


PS,

I have turned it into a 'Word' document, and removed all ships that were under repair or refit to get a clearer picture of just what was immediately at hand in that 24 hour time frame.

 

If the invasion had been launched and defeated, the losses of the Heer would have been quite light. This would have been due to the fact that in the final plan, when they had eventually worked out what their logistical capabilities were, only 3 infantry divisions, 1 airborne division and a small amount of armour was to be landed on S-Tag (their D-Day), and over the next ten days the number of divisions landed would be increased to 9 infantry divisions and 250 tanks of various types.
So even if the Germans had lost everything they attempted to send over on the first ten days (though in my view they would be forced to give up far sooner)it would only amount to a maximum of 10 divisions, (none of which were panzer) in an army with a strength of around 140 divisions

 

Redcoat,

OK, fair comment!

John.

 

Beat me to it.

Odds are the initial assualt would fail and the majority of the invasion army would never set to sea. In the six weeks of the campaign across Holland, Belgium, and France Germany lost what? 55,000 dead & 140,000 wounded? That did not cripple the Wehrmacht nor delay any subsequent campaigns. Thats a aggregate loss of more than the proposed Sea Lion army of 10+ divsions.

The serious loss might the air force, losing yet more highly trained pilots and aircraft than in the Battle of Britian alone. How many more pilots could be lost before the air support in 1941 is significantly degraded?

 

It seems to me they would have had to have at least some of the barges powered because they certainly wouldn't have had enough tugs to tow all of them. The rate of advance would still be about 3 knots however since they would have had to stay together for protection by the escort.

Interesting that the Germans deemed the test exercise a success considering the results. Landing craft which broach in the surf and end up on their beam ends parallel to the surf line are almost always lost or badly damaged. Not only does that reduce the follow up waves because the barges are not available, it also reduces the beach frontage available for landing. This was a serious detrimental factor in a number of amphibious landings the US conducted. Even under the best of conditions, not having proper vessels , equipment, and training would be a severe handicap for the Germans.

As for unloading the river barges, I'm puzzled by just how they were supposed to be unloaded at all. The contemporary pictures I've seen of the barges in question do not show any cargo handling gear (hoists cranes, gibs, etc.) whatsoever. The river barges were clearly designed to be loaded and unloaded alongside a pier or jetty equipped with cranes. If the barges were beached in the conventional manner (for assault landings), they would have to be unloaded over the bow, yet that would prove extremely awkward and slow, and for certain heavy items and vehicles (jeeps, motorcycles), damn near impossible. Tanks, trucks, heavy artillery, of course, would be out of the question.

Also the extreme length of the barges compared to regular landing craft, would make it almost impossible for them to be held bow-on to the beach for any period of time. The only solution I can see to that problem, would be to stream a kedge anchor off their stern as they beached. The US tried this method from LST's when conditions were prone to cause them to broach. But it's extremely tricky, requires excellent seamanship, and still caused problems, like fouling the props in the anchor rodes, when the ships retract. A situation like that on a crowded and busy beach, under enemy fire, can disrupt an entire landing so the USN avoided such measures whenever possible.

I can only conclude that nobody on the German planning staff had given much consideration to the question of moving anything, but troops across the beaches.

 

The real problem might be the barges. They were the lifesblood of commerce and industry in western Europe. The losses of so many would cause problems for some time after. There's also the propaganda/prestige problems.

I think it's this thread that goes into considerable detail on the barges:
http://forum.axishistory.com/viewtopic.php?f=54&t=119663&hilit=+sea+lion