US Army OOB

[MarkSheppard]

Small nitpick on the Pershing as found in

Unit 015; T26 Pershing
and
Unit 106; T26 Pershing

The Pershings deployed to Europe were T26E3 models (the model picked for full production), and in March 1945, the T26E3s were standardized as the M26.

Source: Hunnicutt's Pershing.

[DRG]

OK

Don

[MarkSheppard]

The T26E4 was delivered to the 3rd Armored Division's Maintenance Battalion on March 15, 1945; consequently saw ten days of actual combat before V-E Day.

Attached is my rendition of the T26E4 turret using the SPCAMO M26 turret. The T26E4 used the same hull as the normal M26.

Data:
5 man crew
406" Length with Gun Forward
138.3" Width over Sand Shields
109.4" Height to Cupola Top
96,000 lbs combat loaded weight

Armor on both hull and turret is the same as the normal Pershings.

90mm T15E1 Gun with 54 rounds (4 RPM with loader)
.50 Cal AAMG
.30 Cal M1919A4 Coax
.30 Cal M1919A4 Bow MG
440 rounds of .50 Cal
5,000 rounds of .30 cal
20 MPH sustained speed on level roads

-------

90mm T15E1 Gun Data:
70 Calibers

Penetration:

T43 AP Shot (APBC-T; 3,200 ft/sec)
132mm @ 30 degree angle @ 500 yds
127mm @ 30 degree angle @ 1000 yds
124mm @ 30 degree angle @ 1500 yds
122mm @ 30 degree angle @ 2000 yds

T44 HVAP Shot (APCR-T; 3,750 ft/sec)
244mm @ 30 degree angle @ 500 yds
221mm @ 30 degree angle @ 1000 yds
196mm @ 30 degree angle @ 1500 yds
173mm @ 30 degree angle @ 2000 yds

EDIT: Again, the data is from Hunnicutt's Pershing.

[cbo]

MarkSheppard said:
The T26E4 was delivered to the 3rd Armored Division's Maintenance Battalion on March 15, 1945; consequently saw ten days of actual combat before V-E Day.

<SNIP>

Armor on both hull and turret is the same as the normal Pershings.



Even though the E4 had the same armour thickness as the M26 (T26E3), it was up-armoured by the 3rd Armored Division maintenance battalion before being released for combat. They added a vertical slab of 80mm armour cut from a Panther to the gun mantlet, making it 114mm + 80 mm = 194mm. Additional protection for the front hull was made in the form of 38mm "boiler plate" that was welded together to form a new, angular nose that could be welded on to the hull front. Judging from the description, this was not armour quality steel, but rather some plate found lying around in an abandoned factory. The hope was that the new nose would be more inclined to bounce off incomming rounds because the slope was better then the basic M26 hull and that the gap between the new improvised nose and the hull would also help prevent hull penetrations.

In reality, they basically wrecked the T26E4 as the added 5 tons of weight was all on the front, making the tank extremely nose-heavy and it ended up in a tank dump in Germany immidiatly after the war. The other 25 T26E4s never left the USA and eventually ended up as targets.

So if the tank you want to introduce to the game is the one-off vehicle that actually made it to the fight in Europe in 1945, then it should have the added armour and possibly lower speed due to the extra weight and the overloaded suspension.
It it is supposed to be a what-if vehicle representing the basic T26E4 that might have entered combat later in the war, then the standard values apply.

Also, as the tank fired two-piece ammunition, the rate of fire was reduced from 8 RPM to 4 RPM, so in game terms, whatever the ROF of the M26/T26E3 is, it should be halved.

Claus B

[MarkSheppard]

Also, as the tank fired two-piece ammunition, the rate of fire was reduced from 8 RPM to 4 RPM, so in game terms, whatever the ROF of the M26/T26E3 is, it should be halved.



No, that was from the second T26E4 pilot onwards. The first pilot of the T26E4 (the one that was shipped overseas) still had the T15E1 gun with it's fixed, one piece ammunition.

[MarkSheppard]

So if the tank you want to introduce to the game is the one-off vehicle that actually made it to the fight in Europe in 1945



Give me a few minutes and I can come up with the icon for that one to complement the "as built" icon I posted earlier. http://forum.shrapnelgames.com/images/smilies/wink.gif

EDIT: Aaaand here we are; a normal T26E4 icon, and the 3rd AD modified T26E4 icon, plus a LBM of the modified T26E4.

http://forum.shrapnelgames.com/images/smilies/evil.gif

[MarkSheppard]

M36B1 Tank Destroyer:

Due to a high need for 90mm guns in the ETO; 187 M4A3 Medium tanks were converted by Fisher to have the M36 turret instead. Despite having a higher silhoulette; these were the most heavily armored tank destroyers the US deployed in WWII; and the only ones with a bow machine gun.

[cbo]

MarkSheppard said:
No, that was from the second T26E4 pilot onwards. The first pilot of the T26E4 (the one that was shipped overseas) still had the T15E1 gun with it's fixed, one piece ammunition.



You're right http://forum.shrapnelgames.com/images/smilies/happy.gif

Claus B

[MarkSheppard]

You're right



I think the best thing to do would be to include the 24~ T26E4s produced with the T15E2 two-piece ammunition as a "prototype tank"; and put the 3rd AD modified Super Pershing icon in so that scenario designers can do ones built around that specific tank.

[The_Warrior]

-------

90mm T15E1 Gun Data:
70 Calibers

Penetration:

T43 AP Shot (APBC-T; 3,200 ft/sec)
132mm @ 30 degree angle @ 500 yds
127mm @ 30 degree angle @ 1000 yds
124mm @ 30 degree angle @ 1500 yds
122mm @ 30 degree angle @ 2000 yds

T44 HVAP Shot (APCR-T; 3,750 ft/sec)
244mm @ 30 degree angle @ 500 yds
221mm @ 30 degree angle @ 1000 yds
196mm @ 30 degree angle @ 1500 yds
173mm @ 30 degree angle @ 2000 yds

If these number are right. Then the gun on the normal M26 was more powerfull but I thought the T15E1 was suppose to me a better gun with the longer barrell and all.

Art /threads/images/Graemlins/Flag_USA.gif

[MarkSheppard]

If these number are right. Then the gun on the normal M26 was more powerfull but I thought the T15E1 was suppose to me a better gun with the longer barrell and all.

The gun on the normal Pershing was; from Hunnicutt's Pershing:

90mm M3 Gun Data:
52.5 Calibers

Penetration:

Early M82 APC Shot (2,650 ft/sec)
120mm @ 30 degree angle @ 500 yds
112mm @ 30 degree angle @ 1000 yds
104mm @ 30 degree angle @ 1500 yds
96mm @ 30 degree angle @ 2000 yds

Late M82 APC Shot (2,800 ft/sec)
129mm @ 30 degree angle @ 500 yds
122mm @ 30 degree angle @ 1000 yds
114mm @ 30 degree angle @ 1500 yds
106mm @ 30 degree angle @ 2000 yds

M304 HVAP Shot (3,350 ft/sec)
221mm @ 30 degree angle @ 500 yds
199mm @ 30 degree angle @ 1000 yds
176mm @ 30 degree angle @ 1500 yds
156mm @ 30 degree angle @ 2000 yds

[The_Warrior]

Ok. So do you now how they come with penetration numbers for the game? I under stand the Armor ratings. If I did it right, the modified Super Pershing should have frontal armor of 18 for the hull front and 19 for the turret front.

Art. /threads/images/Graemlins/Flag_USA.gif

[sturmovik]

I was investigating the Super Pershing myself today and there are some fairly consistent penetration values for the 90mm T15E1 L73 gun, but the value seem to be a bit fantastic. Perhaps people could comment a bit?

330mm @ 30 degree angle @ 100 yds
240mm @ 30 degree angle @ 1000 yds
Panther Hull @ 2600 yds


The 90mm L73 T15E1 gun was an attempt to provide the same kind of performance as the German 8.8cm PAK 43 anti-tank gun. Like the German gun in addition to the longer barrel the gun fired ammunition with a larger propelling charge. Muzzle velocity firing the T30E16 projectile increased from 3,350fps to 3,750 and T33 from 2,800fps to 3,200fps, increasing the range at which a Panther hull front could be penetrated to 2,600 yards! Originally the T15 used one-piece ammunition but at 50-inches long it was too bulky to handle in a tank turret so a redesign was undertaken to employ 2-piece seperately loaded rounds, which became the T15E2 to be mounted on the Heavy Tank T26E4. Even with 2-piece ammunition the cartridge case extended past the turret ring during loading which could cause problems at anything other than level elevation.

http://answers.yahoo.com/question/index?qid=20090818013116AAroXQM
http://www.3ad.com/history/news/super.pershing.1.htm

[Cross]

Here is the penetration according to a classified US Army document dated June 1945:

https://dl.dropbox.com/u/28868437/Forum%20Images/US.Gun.Pen.Primary.Doc.png

Taken from:

WAR DEPARTMENT FIELD MANUAL
FM 6-40
FIELD ARTILLERY GUNNERY
1 June 1945


Cross

[Cross]

Here's the armour thickness they could penetrate at 30 degrees:

https://dl.dropbox.com/u/28868437/Forum%20Images/90mm.pen.png


ps. Panther front hull is 85mm, at 55 deg it would be 148mm


Cross

[sturmovik]

Those are for the standard 90mm L53 guns. Does anyone have info on the 90mm T15E1 L73?

[Cross]

Those are for the standard 90mm L53 guns. Does anyone have info on the 90mm T15E1 L73?


Post #3 on this thread has penetration data for the L73, and as pointed out it performance is worse than the L53!

I looked on the internet and found 4 other sources/mentions of penetration. Out of the 5 only one (source 3) gave the L73 better penetration than the L53!

The PEN in bold didn't mention 30deg.
So source 3 would be 258mm at 30deg at 500yds, which is only 11mm better than the L53:

https://dl.dropbox.com/u/28868437/Forum%20Images/90mm.sources.png


Cross

[sturmovik]

Hmmm, that's odd. The propaganda clearly states that it was better.

[Cross]

Only one T15E1 gun (with extra long single piece round) was produced, and that gun saw combat. But if there was only one, it may be tough to get data for that gun.

I read somewhere that Hunnicutt's penetration was for the T15E2 gun; post #3 says the T15E1 gun! I don't know which is correct. 25 of the T15E2 were apparently produced, and they had two piece ammo.

You would expect the extra fps over the L53 to give better penetration, unless there was something inferior about the two part shells for the T15E2.

The numbers are so close between the L53 and L73 that it could be that someone mistakenly published the L53 data as L73 and the mistake was then copied in other places.

Perhaps source 3 was the only correct data, and they forgot to mention it was at 30deg?

Keep digging and you may figure it out.

I'll see if can find a good source if I get time.


Cross

[Imp]

Hmmm, that's odd. The propaganda clearly states that it was better.

Perhaps not so odd the key word being propaganda:D
Nothing like a morale booster for the troops we have a whizz bang super piece of kit for you guys.
USA tank guns suffered from constant meddling by the arty arm nearly resulting in guns that are designed with there requirements in mind. Normally that's simplicity reliability & a good barrel life but with the net result of poor penetration performance.