Its amazing how even on a board with generally high qualities of contributions there can still be such astounding ignorance, blatant mistakes, misconceptions, and errors about the Maginot Line.
Once the German blitzkrieg breaks through since the French think breaching the Maginot Line is impossible there are next to no troops behind said fortification. The Germans then sweep into France.
There are plenty of OOBs about French troop deployments for one. To give an overview of the troop deployments on the Maginot Line:
Historically keeping so many internal divisions in the line was a rather puzzling mistake, the French didn't need to do that and the whole point of the line was to delay an attack and it could have been easily reinforced with reserves, and thus they could have gotten away with substantially fewer numbers there. But if the Germans are being so generous as to attack them, well....
Dear
@lionhead I'm afraid you grossly overestimate the value the Maginot-line actually had.
Could be helpfull to remember/reading how "well" it
fared against german troops, where they actually had to attack it in the beginning phase of the western campaign. They hold up to a couple of days max.
A german 'achievement' not at last helped by having a 'proper' training range in the Czechoslowakian and very similar fortifications.
Also might be helöpfull to look how the Maginot-line was actually built. Not :
like this. It actually was planned and built as
a/one line. The concept of bunkers in depth, best with overlapping arcs of fire was realized in the later german West-Wall.
And this 'line' was NOT over the whole length like this :
View attachment 415315
... though the french propaganda tried to let it look alike such elaborate constructions were rather the exeption than the rule.
(Reading at least the wiki-article about might be helpfull)
So :
IF the germans - for whatever reason - would have decided to go 'through' the maginot-line, they would have properly prepared it by :
- intense training and an even more thorough assessment of czechoslovakian buildings
- intense search for the 'right' spot to break through ... which most likely would NOT be the strongest fortress point
- aside search for 'good' spots for deceptional attacks
- most likely the 'right' eqipment like bunker-buster bombs or napalm-analogs (don't think that any kind of the lines turrets would not have some ... 'malfunctions' after 4-6 hours burning outside, aside from not being usable during this time) just to name a few possibilities.
- not the last to be considered : the armament, esp. the 'more heavy' were rather outdated and easily 'bested' by german artillery in 1940, which could put pin-point fire against them on distances well out of reach for any counterfire.
and it wouldn't have taken more than a couple of days max. to break through their choosen point or points.
Aside the 'flanking' positions at the Montmedy-sector of the line the germans IOTL simply did not and did not have to put much of an effort to overcome the still manned fortifokations after 'Case Red' had sufficed.
However, I well agree, that strategically it most likely would not have been a better decision ... though ... without invading Belgium and the Netherlands ...
This is quite painfully ignorant, and goes to show you why you should never fully place your sources upon wikipedia.
1)The region of the Maginot line which the Germans attacked in the north at Sedan was not the Maginot line proper: only a small section in the north was taken and even there it was only a petit ouvrage which fell, after determined resistance. La Ferté was cut off and without support from the rest of the line, and certainly is NOT a good example of the results of an attack into Alsace or Lorraine with the two equipped with their internal divisions.
To quote
The Maginot Line: History and Guide concerning why the usage of Maubeuge is faulty to refer to the rest of the line:
The ouvrages built as part of the New Fronts, like those on
the Maginot Extension and at Maubeuge, had a particular
vulnerability to ground assault because they used the GFM
Type B cloche. This type of cloche did not take the 50mm
breech-loaded mortar – the only weapon that allowed high-
angle fire against troops seeking cover in craters or other
positions taking them out of the direct line of fire of other
standard weapons. The 81mm mortar and 135mm lance-bombe
turrets, which would have been adequate for the job, were not
used in the forts of the New Fronts. Thus German troops
advancing from crater to crater only had to concern themselves
with the direct fire weapons of the French positions. Once they
reached the surface of a block, they could use their demolition
charges unimpeded. La Ferté received only limited assistance
from the nearest ouvrage, since it was barely within range of
its 75mm guns. Other positions north of the Maginot Extension
did not even have this advantage because their field artillery
support units had already withdrawn and there were only two
casemates mounting 75mm guns and one special casemate
with a 155mm gun. In addition, their façade walls were rather
thin – 1.5 metres – to make their recapture easier. Once the
Germans made their way behind these positions, they could
take advantage of their Achilles heel, as they did at several
locations, including on the Maginot Line Proper.
-
One might note that even limited fortifications like La Ferté or Les Sarts still lasted several days despite massive utilization of air-power, direct fire artillery, and heavy artillery. That isn't a good record for going against the much heavier fortifications along Alsace or the painfully forbidding geography of a Rhine assault.
2)The attack on the Rhine section was done after the withdrawal of the internal divisions required to provide for their defense, and even still results were generally ineffective.
3)No gros ouvrage of the Maginot Line actually fell, and the German attacks in the Alsace sector were beaten back repeatedly with heavy casualties. Particularly one should refer to the German attacks in the Saare sector and Metz which held despite the presence of multiple German 420mm howitzers until manning troops were ordered to fall back or retreat. Type 4 protection in particular was explicitly designed to offer resistance to 420mm bombardment, the largest guns the Germans had.
One note which should be made is the attack on GO Fermont, when the artillery of a German infantry division, 210 mm howitzers, and a 305 mm mortar failed to make any impression.
4)There was no such thing as 'more heavy' armament in the Maginot Line, so I would recommend that you purchase a book upon the subject.
The Maginot Line: History and Guide is an excellent primer. Maginot Line artillery consisted of 75mm cannons, 81mm mortars, and 135mm mortars, with a few exceptional 120 mm guns mounted in an improvisational matter, and it was not supposed to be equipped with its own integral heavy artillery. That was provided by mobile forces, and the heavy artillery which the French had was certainly more than a match for whatever the German army had - I would recommend that you look at the mobilized equipment tables which French Armament 1939-1940 provides. Generally even when mobile forces heavy artillery were withdrawn Maginot Line positions put up substantial resistance: with them they are a far more dangerous and hard nut to crack.
To provide the heavy artillery which the French had:
Heavy field artillery mobilized in May 1940 :
120mm L Mle1878 and 1916 : only few mobilized to reinforce fortified areas (600 available)
145/155mm L Mle1916 : 68 (168 available)
150mm T Mle1917 Fabry (tranch mortar) : about 866, at least 360 during the Phoney War (1159 available)
155mm L Mle1877 : 743
155mm L Mle1877/14 : 480
155mm L Mle1918 : 120
155mm L Mle1917 : 407 (535 available)
155mm GPF : 352 (449 available)
155mm GPFT : 24
194mm GPF (tracked SPA) : 26 (49 available)
220mm C Mle1916 (heavy mortar) : 376 (462 available)
220mm L Mle1917 : 56 (68 available)
240mm LT Mle1916 (heavy trench mortar) : 12 (410 available)
270mm M (coastal heavy mortar) : 24 available, probably none mobilized
280mm C PF (heavy mortar) : 100 (PF = plateforme = plateform) (109 available)
280mm C Ch (tracked SPA) : 26 (Ch = chenille = tracked)
370mm M Fillioux : 4 (12 available)
TOTAL 2 : 3,684 guns mobilized
Rail road artillery mobilized in May 1940 :
164mm : 4 (8 available)
194mm : 24 (32 available)
240mm : 16
274mm : 16
293mm : 5 available but not mobilized
305mm : 6
320mm : 16
340mm : 8 (10 available)
370mm : 13 available, none mobilized
400mm : 10
520mm : 1 available, not mobilized
TOTAL 3 : 100 guns
5)Those forts which surrendered generally did so when their interval troops and their accompanying artillery were withdrawn. Those units would still be positioned at the Maginot line in the event of any German direct attack.
6)The large fortifications are of a size which makes suppressing them via destruction of their air inlets almost impossible, and proved highly resistant to German heavy artillery. Aircraft rarely had the accuracy to be much of an impact on the forts, aircraft are more useful for interdicting them - but as long as you have underground track and massive supplies and autonomy for the fortifications like the French did, that doesn't work very well.
7)The Americans used substantial quantities of napalm against the Germans during the 1944 attack, with little effect. As noted for the attacks on Fort Driant:
When the US 3rd Army came within range in
September, the guns of Fort Driant interfered with
their river-crossing operations. The Army Air Corps
was called in to bomb the old fort, but the P-47s’
500lb (240kg) bombs had little effect. Later napalm
was dropped, and the American heavy artillery,
including 8-inch guns and 240mm howitzers, went
into action, but inflicted little or no damage. From
late September until 12 October the 5th Infantry
Division, also using attached armour, besieged the
fort.
Or another incident with usage of napalm
In 1944, as the German armies retreated across France, the
army re-evaluated the old festen in the West. About 550
German troops with seven artillery pieces remained in the town
of Mutzig and in the fort when the American 3rd Infantry
Division approached in November 1944. The Germans
retreated, leaving about 200 troops surrounded in Fort Est.
American 155mm guns damaged the fort and aircraft dropped
napalm, but the garrison survived. Its only serious problem was
a lack of supplies, so at the beginning of December the
Luftwaffe tried to parachute in provisions, but most of the
containers fell into the American lines. On 3 December the
American engineers used a bulldozer to clear a path from the
glacis into the gorge (the rear of the fort with the exposed
façade of the caserne). Next, they drove a captured armoured
vehicle loaded with 4 tons of explosives into the fossé and
detonated it. The massive explosion heavily damaged the
façade of the fort. The Germans tried to break out that night,
but on 5 December, without supplies, they were forced to
surrender. Fort Est was still in reasonably good condition with
only one 57mm gun turret knocked out.
2
So there is no real evidence that napalm or napalm equivalents worked effectively against Maginot line fortifications.
9)Life support systems for the forts were the equivalent of 30 meters under ground at least, although in hard rock regions that sometimes dipped to 12 meters.
9)Trying to send in assault troops is going to be a difficult prospect since along the line proper, all of the fortifications were self-supporting and could fire to clear accompanying forts of troops on their surface. The same thing can be said about glider troops.
10)Fundamentally, even if you do make a breach and take one of the sections of the line, it is a far smaller breach than the breakthroughs the Germans achieved at say, the Meuse with Sedan. And unless if you can take out surrounding fortifications as well - which means that at a minimum you have to be engaging 3 formidable targets - then you're going to be facing a constant stream of fire from surrounding forts on your lines.
What you're looking at for an attack upon the border sections of the Maginot line is not a few days to break through, but exceedingly and painfully quickly bogging down as the French interval troops make any attack infeasible once they are in position to support and it degenerates into a battle of attrition, one which the French have every advantage in thanks to their massive surplus of heavy artillery, the bad geography and/or prepared fortifications lines. There's a good reason why the Germans didn't attack into it.
