SAu 40

SAu 40

Lorraine 37L

SAu 40

Lorraine 37L

France

I Rank

Battle rating:

AB	RB	SB
1.7	1.7	1.7

Class:

Tank destroyer

Research:5 900

Purchase:6 300

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Description

The Canon Automoteur DE 75 mm SAu 40 (DE 75 mm Self-Propelled Gun SAu 40) is a Rank I French tank destroyer with a battle rating of 1.7 (AB/RB/SB). It was introduced in Update 1.75 "La Résistance". It distinguish itself by its very tall cupola and thick gun barrel. This tank is equipped with APHE rounds, a rare feature in the French tech tree.

As it was developped from the French S.35, this tank shares many of its characteristics such as ~40 mm cast hull bolted onto the chassis, which is barely a widened version of its original. The track system is mostly the same as on the S.35, with 25 mm plates covering the roller wheels. As for the hull, its two 8 mm grilles over the engine compartment and doors on the side reinforces the impression that it's just a widened S.35 hull.

General info

Survivability and armour

As this tank is based off the S.35, it shares many of its attributes when it comes to armour. A slight angle can defeat most shots this tank will take at this BR, this is useful to know when getting into position: from a distance and not showing neither side nor front to the enemy, you should be safe. As for frontal armour, its 40 mm overall thickness is not strong enough to withstand anything bigger than AA fire. But, a thing to consider with this weird pattern is its "bouncy" behaviour, principally around the gun mantlet: complex angles may just bounce some shots, making them loose some energy before hitting the main armour, this feature is peculiarly distinctive at gun's height.

The main weakness of this tank is its very tall commander's cupola, which makes it quite easy to spot and destroy, as it is thinner than the main armour. Any APHE penetrating this area will knock out the tank's commander, thus disabling its only MG and some shrapnels may even damage or incapacitate the driver, disabling this tank for good. A way to avoid getting spotted too easily is buying camouflage for the front cupola area, making it look more like a bush popping out a hill than a tank's turret. Try to hide the tank's lower hull part as it is only 35 mm thick.

Armour type:

• Cast homogeneous armour

Armour	Front (Slope angle)	Sides	Rear	Roof
Hull	40 mm (0-73°) Front glacis 34 mm (1-54°) Lower glacis 60 mm (0-53°) Gun mantlet	40 mm (0-24°), 34 mm (43-63°) Top 40 (1-3°) + 25 mm (0-89°) Bottom	34 mm (20-49°) Top 34 mm (4-71°) Bottom	20 mm 8 mm Engine grille
Turret	38 mm (5-48°) 25 mm Gun mantlet	38 mm (16-38°)	38 mm (11-38°)	20 mm 34 mm Dome

Notes:

• Suspension wheels are 15 mm thick while tracks are 20 mm thick.
• Turret underside is 20 mm thick.
• Turret ring is 30 mm thick.
• Turret base is 34 mm thick.

Mobility

Game Mode	Max Speed (km/h)		Weight (tons)	Engine power (horsepower)		Power-to-weight ratio (hp/ton)
	Forward	Reverse		Stock	Upgraded	Stock	Upgraded
Arcade	41	6	24	270	363	11.25	15.13
Realistic	37	5		168	190	7	7.92

While being mounted on a widened S.35 hull, the heavier SAu 40 has about 70 HP less than its predecessor, making it quite slow and unwieldy. In order to fulfill the task of getting into position, one should choose its route wisely and avoid risky spots as this tank's awful reverse speed and hull turning rate makes it quite bad at hasty retreats. Mobility with the SAu 40 is an issue. It is arguably what makes this tank hard to master as it does not allow for good map placement.

Armaments

Main armament

As any casemate SPG, this tank's main feature is its main gun...kind of. With average penetration rates for this BR with a maximum of 73 mm at point-blank ranges (comparably, the Russian SU-76M penetrates 80 mm with its basic APHE shell and up to 135 mm with APCR shots). While being one of the rare French tank shooting APHE shells, increasing its one-shot potential, this round noticeably fails to explode when flanking enemies as this round takes 25 mm of steel to detonate. Another concern being its slow horizontal traverse, which makes it hard to react to fast-paced situations. This gun placement makes this tank quite vulnerable: being low, it exposes the SOMUA 40 to enemy fire when popping up a hill.

75 mm APX
Capacity			Vertical guidance	Horizontal guidance	Stabilizer
102			-10°/+30°	-7°/+7.6°	N/A
Turret rotation speed (°/s)
Mode	Stock	Upgraded	Prior + Full crew	Prior + Expert qualif.	Prior + Ace qualif.
Arcade	5.3	__.__	__.__	__.__	__.__
Realistic	3.6	__.__	__.__	__.__	__.__
Reloading rate (seconds)
Stock	Prior + Full crew	Prior + Expert qualif.	Prior + Ace qualif.
7.2	__.__	__.__	__.__

Ammunition

Penetration statistics
Ammunition	Type of warhead	Penetration in mm @ 0° Angle of Attack
		10m	100m	500m	1000m	1500m	2000m
Mle1910M	APHE	76	74	66	57	49	42
Mle1917	HE	10	10	10	10	10	10

Shell details
Ammunition	Type of warhead	Velocity in m/s	Projectile Mass in kg	Fuse delay in m:	Fuse sensitivity in mm:	Explosive Mass in g (TNT equivalent):	Normalization At 30° from horizontal:	Ricochet:
								0%	50%	100%
Mle1910M	APHE	570	6.4	1.2	25	90	°	47°	60°	65°
Mle1917	HE	577	6.13	0.4	0.1	675	+0°	79°	80°	81°

Ammo racks

Ammo racks of the SAu 40.

Full ammo	1st rack empty	2nd rack empty	3rd rack empty	4th rack empty	5th rack empty	Recommendations	Visual discrepancy
102	84 (+18)	66 (+36)	42 (+60)	18 (+84)	1 (+83)	Floor only: 18 (+83)	no

Machine guns

As for the turreted MAC 31 MG, it does not helps at anything more than taking down truck-mounted guns. This turret is slow, which negates the possibility of chasing planes with it. It also has poor rate of fire and is low calibre, so even if you manage to hit a plane, it will not do much to it.

7.5 mm MAC 31
Cupola mount
Capacity (Belt capacity)				Fire rate (shots/minute)	Vertical guidance	Horizontal guidance
3,250 (150)				1,350	-9°/+20°	N/A

Usage in battles

The SAu 40 behaves as a classical casemate SPG as it should provide its teammates with superior firepower from medium to far distance, behind the frontlines where it will be harder to flank. As this is its purposed role, this tank has some issues accomplishing it. The first being its relatively low penetration and shell velocity, which makes long range engagements (>750 m)a bit hard to manage. The second being bad mobility, which complicates the task of positioning.

Act as a classical SPG while keeping in mind your slow pace. There is nothing very much interesting nor special you can do with this tank.

Modules

Tier	Mobility		Protection	Firepower
I	Tracks		Parts	Horizontal Drive
II	Suspension	Brake System	FPE	Adjustment of Fire
III	Filters		Crew Replenishment	Elevation Mechanism
IV	Transmission	Engine

Pros and cons

Pros:

• Firepower
  • Decent 75mm cannon with explosive filler gives it good one-shot potential.
  • "Terrific" MAC 31 gun mounted in cupola.
  • Competitive reload time
  • Good HE shells for dealing with SPAAs.
  • Depression and elevation angles are acceptable.
• Armour is quite thick on all sides.
• Gun mantlet area is strong

Cons:

• Commander's cupola is badly designed.
  • Tall commander’s cupola.
  • Turret-mounted 7.5 mm MG does not allow for shooting down planes.
  • Weak, unslopped armour makes it a shot trap
  • Makes it easy to spot while bringing no tactical advantage.
• Slow in all domains.
  • Engine is underpowered
  • Turret is slow
  • Guns feels "lazy"
• Rather weak frontal armour due to bad sloping
• Three crew members can quickly lead to combat efficiency loss.
• Huge ammo rack near gunner makes it easy to one-shot.

History

The SAu 40 self-propelled gun was developed by the SOMUA company between 1935 and 1937 as part of the same order the French cavalry placed for the S35 tank.

The two tanks combined were intended to equip light mechanized divisions of the French army and support the larger “battle tanks” (chars de bataille). The vehicle inherited the S35’s characteristic chassis with a redesigned front section of the hull to accommodate the 75mm APX cannon. In addition, the rotating turret on top of the fighting compartment was redesigned to a commander’s cupola and moved to the side of the vehicle, but the turret’s 47mm cannon was replaced with a single 7.5mm machine gun.

The body of the SAu 40 was ready by 1937, but it couldn’t be immediately completed. Because the cannon was not yet ready to be installed on the chassis, SOMUA engineers had to wait nearly 2 years before the cannon was finally made available. It wasn’t until 1939 that the fully assembled prototype was completed, and orders for mass production were received in October of the same year.

Whether or not any additional vehicles other than the prototype were built or if the vehicle took part in active fighting is unknown.

-From Devblog

Media

The Shooting Range #77 - Pages of History section at 00:31 discusses the SAu 40.

See also

Links to the articles on the War Thunder Wiki that you think will be useful for the reader, for example:

• reference to the series of the vehicles;
• links to approximate analogues of other nations and research trees.

External links

• [Devblog] SAu 40 - The Ugly Duckling

France tank destroyers
Lorraine 40t derivatives	CA Lorraine · Lorraine 155 Mle.50
ATGM	MEPHISTO · AMX-10M
Other	AMR.35 ZT3 · Lorraine 37L · SAu 40 · ARL-44 · ELC bis · AMX-50 Foch · AuF1
USA	▄M10 GMC · ▄M36B2