Maginot line fortifications

[Kiwikkiwik]

Hello, I thought I had better have a look at the Maginot line fortifications because as I've already looked at the German, Japanese and Italian, the French players might feel left out.

The Tourelles are pretty good though one is missing, but the casements etc could do with a little work to properly represent the premier fortification of WW2. There is also quite a bit of stuff missing.

Firstly the tourelles are way too big at size 7. Here are their dimensions
unit 61 Tourelle 135mm 1.05m high by 2.9m wide
unit 60 Tourelle 81mm .60m high by 2.35 wide
unit 59 Tourelle 75mm 1.26m high by 4.0m wide
unit 79 Tourelle 25mm 1.13m high by 2.55m wide
Missing Tourelle25mm 1.03m high by 2.09m wide
unit 85 Tourelle MG .93m high by 1.98m wide
So sizes around 1 would be more appropriate.

To avoid confusion later we should use the correct names for the fortification MGs There are only two MGs ( actually one MG, one Automatic Rifle) used in french fortifications they are the Chatellerault Guns, Mle 1924/29D and Reibel MAC 31 see
http://armesfrancaises.free.fr/FM%20...-29%20(D).html
All weapon 100 8mm FM14 MMG in the casemates should be replaced by unit 98 7.5mm Reibel MG. Game range for 8mm FM14 is 1200m, game range for 7.5mm Reibel is 1500m. Kaufmann in his book Fortress France: The Maginot Line and French Defenses in World War II. states the effective range of the 7.5mm Reibel MG as 1200m.
Weapon 95 7.5mm FM29 LMG is Mle 1924/29D Kaufman gives this an effective range of 500m, game has 600m. Kaufman gives the shorter range because the weapon is an automatic rifle rather than a LMG.
There is nowhere to poke a rifle out of these casements, tourelles or clouches, so these need to be removed, most weapons are in a ball mount like tank MG, so no open embrasures. The French did have a shute you can drop a grenade out of mounted in casements, the "goulotte" lance-grenade. These were used in conjunction with a deep concreted ditch (fosse) around the block.
Missing in the game, the 50mm Mle 1935 fortress mortar. This weapon was developed from the Infantries Lance Grenades de 50 mm modèle 37, which is also missing.

Let's compare the casements illustrated in Kaufmanns book with those in the game. Luckily the relevant part of Kaufmanns book is available here.
https://books.google.com.au/books?id...page&q&f=false
Looking at figure 2-8 its clear that the 4 game casements could do with some work, we could change them into something more accurate fairly easily.

Unit 55 Casemate Mitrai. Two 8mm FM 14 MMG, 7.5mm FM29 AR, Mle16 Rifle. Could be Block 24 Hackenberg this has two JM MGs. JM (jumelage de mitrailleuse) is the designation for twin mounted MAC 31 so this could be four 7.5mm Reibel MG or If you wanted to create a twin 7.5mm Reibel MG, ie a (2) then have two of them and a grenade ("goulotte" lance-grenade) in each of the other two slots.

Unit 64 Casemate 75mm. 75mm Mle 1897FG, 8mm FM 14 MMG, 7.5 FM29 AR, Mle16 Rifle. Easily changes into Block 25 Hackenberg. Change 8mm FM 14 MMG into JM(2) change Mle16 Rifle into 50mm mortar, leave the FM and FG. 50mm Mle 1935 has a range of 800m, but when mounted in a GFM clouche this drops to 600-695 owing to max elevation of 20 degrees. Correct designation for 75 Mle 1897FG would be 75mm 29 or 32 or 32R or 33.
see
https://wikimaginot.eu/V70_glossaire...?id=%201000020
According to Kaufmann the casement 75mm guns are almost always mounted as pairs or triplets, not singly as in the game. So you might create some new French casements. From figure 2-8 there is block 8 which has 3 75mm's, and could add a grenade in the fourth slot. Or block 5 with 3 75mm guns and one 135mm mortar.

Unit 58 Casemate AC. 47mmSA35(L24), Two 8mm FM 14 MMG, Mle16 Rifle. This one is pretty good, replace the two 8mm FM 14 with two MAC 31 or one JM, lose the Rifle and fill the remaining slots with grenades. There are also 37mm AT guns combined with JM in casements though not in the game at the moment. As a matter of interest the 37mm and 47mm AT gun installations had either the AT gun or the JMs occupying the single firing port so they couldnt fire at the same time but I guess in game terms it is OK to have them all fire at once

Unit 65 Casemate AC. 25mm SA34 L/72, one 8mm FM 14 MMG, 7.5 FM29 AR, Mle16 Rifle. These were mounted with a JM, so keep the 25mm, replace the 8mm FM 14 with two MAC 31 or one JM, lose the rifle, add grenades.

Local defence for these casements was usually entrusted to GFM cloches. Some had 5 crenels all round view, some had 2 or 3 for about 140 and 210 degrees view. Each crenel could mount either the 7.5mm FM29 LMG/AR or the 50mm mortar, not both, though they could both be mounted in separate crenels giving simultaneous fire but in different directions. So for the 5 crenel version, same as with the German cloches the weapon could be mounted in any of 5 equally spaced crenels giving all round fire. So game fixed GFM cloche needs to be able to turn like a turret to emulate this. The biggest is 1.6m wide and about a metre high. The gun or mortar fires through a ball mount so even the crenel is very resistant. As a unit these would have 2 or 3 empty weapons slots. GFM Cloches have armour of 20, 25, or 30cm.
There is also the JM clouche with just the twin MG (JM), so 3 empty slots and has just the one crenel. Can be 20cm sides and 15cm top or 30cm sides 25cm top. or 25cm sides and top. Its no more than 2m wide and about 1m high.
The AM clouche has a 90 degree firing angle achieved by using one or the other of its two crenels, AM clouche has two MG (one JM) and one 25mm AT, so 2 empty slots. 2.5m wide about 1 m high. The 25mm AT in the clouche (but not in the turret) had the barrel cut down from 180mm to 118mm this dropped the effective range down to 400m and penetration at this range from 40 to 35mm.

Unit 336 Maison fortifie. Two 8mm FM 14 MMG, 7.5 FM29 AR, Mle16 Rifle. According to
https://conflictuel.pagesperso-orang...ginot_Line.pdf
This unit, Fortified house has one 37 AT, two FM 24/29 AR, two VB grenade launchers, three "goulotte lance-grenade" grenade droppers, but no FM 14s. So there could be several versions of this type of fortification. The walls are 25cm thick masonry over 1m concrete front sides and half metre concrete roof and back so game armour values are too low. Crew is 6 so can't fire all the weapons at once. At the end of this post is a link to a site that has an illustration of this pillbox which is specific to the Ardenne. Looking at the picture sensible armament would be 37 AT, one FN, one rifle grenade, one grenade dropper (grenade).

Unit 330 strongpoint 25mm SA34 L/72, two 8mm FM 14 MMG, 7.5 FM29 AR is probably meant to be a pillbox, there are many versions of this. Can be 25mm and 8mm FM14 MMG and 7.5 FM29 AR or 25mm and 8mm FM14 MMG or 25mm and FM29 with two empty slots, Pillboxes with single 25mm and single MG or AR also exist. You can see the reference at the end of the post for the arrangements of the various pillboxes.

Unit 329 Shelter bunker. Probably the Maginot line is the only fortification with shelter bunkers that could actually hold 40 men. If shelter bunkers represent Ouvrages then minimum armament is the 95 Mle 1924/29D. They also very commonly have a unit 58 casement included to cover the entrance. ie a 47mm AT and a JM.
Missing in the game is the casement mounted just a twin Mle 1930 13.2mm MG so 3 empty slots. As mounted these weapons have an effective range of 800m.
Missing in the game are the french tank turrets mounted a la panzerturm. From the same reference, they are Renault FT17 or FT31 turret with a Mle1914 Hotchkiss or a MAC31 MG and the turrets Mle1935 and Mle1937 (also known as STG) armed with a Mle1914 Hotchkiss MG, weapon 100 8mm FM14 MMG. STG has 30mm top armor and 40mm side armor, another source gives armour of between 23 and 35mm.

Which brings us back to the Tourelles

A 25mm Tourelle is missing, which has two 25mm AT and four Reibel MAC 31 ie two JMs. This tourelle has 28.5cm roof 18.5cm sides. 25mm AT gun barrel shortened from 1800 to 1500mm.

The 135mm Tourelle turns out to be a strange beast indeed. The French Idea for this weapon is that it is actually an artillery 'battery' under armour and just like an artillery battery a remote observer is used to call in the weapons fire on target. Unfortunately unlike an artillery battery when approached by the enemy directly it was unable to fire directly at said enemy, There are two reasons for this. First it is blind. Second they are emplaced in a concrete dish, so no LOS to the target anyway. They were emplaced this way to make it impossible for the enemy to fire at it, until they are right on top of it.Minimum elevation is 9 degrees and minimum range for the weapon is 320m. So somewhat problematic.
Here it is in its concrete bowl.
https://eurotravhist.files.wordpress...kb-turret1.jpg

The 81mm mortar has the same configuration, and the mortar is permanently fixed at 45 degrees, and as with the 135mm Mortar it is blind. It also lives in a shallow concrete bowl to stop direct fire weapons being able to fire at it. Minimum range is 100m It is hard to make out that the 81mm mortar Tourelle is in a bowl in most photos but it's clear here in this photo showing that the bottom edge of the tourelle roof lines up with the outside edge of the concrete bowl.
https://wikimaginot.eu/V70_glossaire...php?id=1000222
So for the French 135 and 81mm tourelles there is the same problem as for the German 50mm and 81mm mortars emplaced in Tobrucks they both need to be able to fire indirect only. With the tobrucks you could pop out the top and fire a rifle or throw a grenade in self defence but for the two french tourelles this is not possible, so no direct fire in any form is possible from them.

Tourelle 135mm has top and side armour of 30cm so the game values of 40 25 and 15 should all be 30. Same applies to the 81mm tourelle.

The game tourelle 25mm, unit 75 is close to one of the 25mm tourelles except it is missing its 50mm mortar. see figure 2-7 at the google review. The mortar fires through its own opening and could be added into the unit's empty slot. The barrel of the 25mm AT gun in this installation was cut down from 1800 to 1500mm. top is 35cm sides are 30cm.

There are several 75mm Gun/Howitzers and Howitzers in the maginot line and one 75mm mortar (75mm Mortar Mle 1931, mounted in casements singly or in pairs. capable of direct fire and missing in the game). The 75mm guns are listed here.
https://conflictuel.pagesperso-orang...ginot_Line.pdf
Ammunition includes HE, APHE and Smoke. Ranges can be quite different.
The 75mm tourelles had 18.5 sides and 28.5cm tops or 30cm sides and 30cm tops or 30cm sides and 35cm tops. They usually fire through a ball socket, so very tough. Unlike the others the tourelle for the 75mm 32 R gun was for AT use. It is smaller than the other 75mm tourelles at 3.04x1.02 and has armour of 30cm all round, as does the MG tourelle, unit 85.
This site gives some penetrations for the 75mm ammunition.
https://forum.axishistory.com/viewtopic.php?t=117605
Obus de rupture Mle1910M (APHE) Penetration : 71.5mm /0° at 100m and 61.5mm /0° at 500m
Obus perforant AL (Allongé Lefèvre) Mle 1916/18 (APHE) Penetration : 40mm /30° at 400m
It seems all the Ammunition in 75x350R mm was freely interchangeable between the various fortification 75mm guns.

Uniquely to the French the underground aspect of these fortifications was incredible. battleship like.
This is reflected in the ammunition allocated. From
https://conflictuel.pagesperso-orang...ginot_Line.pdf
Ouvrage Schoenenbourg had
• 75mm shells : 16,000
• 81mm shells : 6,400
• 50mm shells : 12,000
• 47mm shells : 2,400
• 7.5mm cartridges : 1,448,000
From elsewhere
Typical individual 75mm gun had 192 AP 6400 HE.
Mle 1924/29D issued 14000 bullets
135 had ready access to 4000 shells.
There are railway lines and chain hoists to ensure there is no delay in getting those shells where they are needed.
So all these fortifications ammo loadouts could be much much greater than they are at the moment.

As with the Germans there was a range of old or captured guns emplaced that are mentioned in the references.
The previous reference mentions that these three guns were used in a supporting role for the Maginot line.
Canon Lahitolle 95mm Mle1888.
Canon De Bange 120mm.
Mortier De Bange 270mm Mle1885.
They might be an interesting addition to the game.
Everything you might want to know about the Maginot line is here
https://translate.google.com.au/tran...search&pto=aue
If you go to the heading "Definitions, principles and explanations" then down to "Dico sections" and select from that list 'weapons - armaments', in there are all the various turrets etc.
Another heading "List of standard plans" shows all the various blockhouses, pillboxes etc that were also in use and have the more "normal" armoured or possibly open style, but closable embrasures. Also an excellent illustration of the "Maison Forte type Ardennes" in this list which is what your unit 336 Maison fortifie . Also illustrated near the bottom of the list, is the 65mm ex-naval AT gun in an open gun emplacement. It would be another useful addition to the game. Penetration for the gun is 50mm @ 30° @400 meters and 40mm @ 30° @ 1000 meters and 30 mm at 1200 meters.
I see this as a marvelous opportunity to add some really interesting depth to the game. Allez les Frenchies.