Interesting comments on artillery effects on tanks

[Hans]

From FYEO

Like any wartime experience, Iraq provided vivid reminders of the way things really worked. Case in point was the effects of artillery on tanks. For decades, it's been conventional wisdom that high explosive 155mm artillery shells (the most common type fired), do not have much effect on tanks. Battlefield evidence in Iraq told another story. But some artillery officers remembered artillery firing tests performed in 1988. It had been over a decade since such tests had been performed, and it was time to see what new ammunition could do against typical battlefield targets. A variety of bunkers, earthworks and structures were built out in a firing range. Also hauled out were various American and Russian armored vehicles and trucks. An artillery battery then proceeded to fire various types and quantities at the various targets. After each firing, an evaluation team went out to take pictures and measure the damage. What was found in 1988, was also found in 2003. As always, hitting a tank with a 155mm shell will knock the tank out of action, and usually destroy it. That, however, is a chance event, as artillery is not accurate to get direct hits on demand. However, whenever a 155mm shell, using a fuze that detonated it on the surface, and landing within a hundred feet of a tank, usually immobilized tanks by damaging road wheels and tracks with shell fragments. Those portions of the fire control system that were outside the tank were also damaged, often enough to disable the tanks ability to fire its main gun. Damage often did the same for machine-guns mounted on the tanks (one atop the turret and the other mounted next to the main gun.) Antennas and anything else outside the tank were also subject to damage. Shells using airbursts, and within a hundred feet of the tank, were less likely to damage the road wheels and tracks, but more likely to damage the engine, the main gun and fire control system, as well as anything else that was outside the tank. Other armored vehicles, having less armor, suffer even more damage. Armored personnel carriers are supposed to have armor that will protect the troops inside from shell fragments. But the 1988 tests, and poking around the 2003 battlefield, showed many of these vehicles (both U.S. and Russian

made) with 155mm shell fragments inside the vehicles, and holes ripped in the armor to show how the fragments got there. It's important to note that many, if not most, artillery use a fuze that sets the shell off after it has buried itself in the earth. This does more damage to troops in trenches, foxholes, bunkers and buildings, but much less to armored vehicles in the vicinity. But many artillery officers know that, in a pinch, 155mm shells with PD (point detonation) or VT (air burst) fuzes) will damage a group of tanks and armored infantry vehicles enough to take the fight out of them.

[lcm1947]

Very interesting review and is what I would expect from a shell that size. Was this supposed to surprise anybody? I am referring to the test not your post by the way.

[Hans]

More a posting of interest. I think it backs up what the majority believe and CM is presently modelled on. Always nice to see evidence of same. With a name like ICM, I would expect you to be interested!

Hans

[Private Bluebottle]

Originally posted by Hans:

But the 1988 tests, and poking around the 2003 battlefield, showed many of these vehicles (both U.S. and Russian made) with 155mm shell fragments inside the vehicles, and holes ripped in the armor to show how the fragments got there.

One would assume that such penetrations would only be likely if the vehicle was not an MBT. Thin skinned AFVs have always been vulnerable to artillery rounds, although, it should be noted even then, most vehicles are supposedly "proof against artillery fragments" in their description.

Its interesting that David Fletcher quotes a test conducted in 1944 with Churchills, driving around inside an artillery bombardment with no ill effect beyond the loss of aerials and a few vision blocks.

[Sergei]

Originally posted by Private Bluebottle:

</font><blockquote>quote:</font><hr />Originally posted by Hans:

But the 1988 tests, and poking around the 2003 battlefield, showed many of these vehicles (both U.S. and Russian made) with 155mm shell fragments inside the vehicles, and holes ripped in the armor to show how the fragments got there.

One would assume that such penetrations would only be likely if the vehicle was not an MBT. Thin skinned AFVs have always been vulnerable to artillery rounds, although, it should be noted even then, most vehicles are supposedly "proof against artillery fragments" in their description.</font>

[flamingknives]

I recall a defensive trial of the Conqueror Hy gun tank in a document I read at the PRO.

As of mid-1950s, 155 VT was capable of penetrating 17mm plate, the top hatches, and 25pr. VT was capable of disabling said tank by means of penetrating ~10mm engine grilles.

As a result of these tests, the hatches were increased in thickness to 31mm, which was sufficient to prevent the problem recurring.

120mm H.E., scoring direct hits, caused minor internal damage, save for one hit that lifted the drivers hatch, causing fragments and blast to enter that area of the hull (obviously fatal for the driver, but not turret crew). Another shot burred the exposed mantlet, restricting elevation of the main armament.

Allowing for the advance of explosives, the effects are not going to be negligable on modern tanks, but I'm surprised that they are expected to be as severe.

ISTR that in the Serbia-Croation war, Croatian anti-material snipers had to use 20mm AMRs to disable the gun sights on Serbian MBTs. Equally, I would not have suspected that fragmanst would be able to damage a co-axial MG unless exposed as per the Merkava or Bradley. On most AFVs it's recessed into a port on the front turret

The APCs I take it are Soviet BMP/BTR models and US M113s rather than Bradleys.

As this pertains to CM:BB - I will happily use 122-152 and bigger on enemy tank formations, especially early war.

[John D Salt]

Originally posted by Private Bluebottle:

[snips]Its interesting that David Fletcher quotes a test conducted in 1944 with Churchills, driving around inside an artillery bombardment with no ill effect beyond the loss of aerials and a few vision blocks.

I assume that the tests referred to are those mentioned in PRO document WO 291/399, "Casualties to Churchill tanks in 25-pdr concentrations", in which case the rounds are about a quarter the size of 155mm shells.

All the best,

John.

[John D Salt]

Originally posted by lcm1947:

Very interesting review and is what I would expect from a shell that size. Was this supposed to surprise anybody? I am referring to the test not your post by the way.

The figure of 100 feet as the distance at which a 155mm shell fuzed superquick can immobilise a tank certainly surprises me. I would have thought 10 feet more likely.

Figures from PRO document WO 291/128 "A theory of fragmentation", show vulnerable areas for 5.5" gun-how HE against different levels of mild steel plate protection that would correspond to circles of the following radii:

80 lb shell filled Amatol 50/50:

No protection________41.5 ft

Quarter inch plate___21.5 ft

Half inch plate______12.5 ft

100 lb shell filled Amatol 70/30:

No protection________42 ft

Quarter inch plate___21 ft

Half inch plate______10 ft

I don't know what level of mild steel plate protection would be equivalent to the vulnerability of running gear, but I would have thought the half-an-inch figure would have been closer than that for no protection. Modern shell design (higher brisance fillings, pearlitic steel projectiles) might offer considerable improvements in performance for modern 155mm over WW2 5.5", but I doubt it is enough to make the vulnerable area against AFV running gear greater than that against unprotected personnel for the older round.

All the best,

John.

[Redwolf]

Modern rounds from 5.56mm assault rifles penetrate sides and rear of the older Russian APCs just fine. Full-size 7.62 (MGs, sniper rifles) would have less problems and can also harm sides and rear of BMPs. A M113 is certainly vulnerable to full-size 7.62 rounds.

Artillery really has a harder time than smallarms. Steven Zaloga's book "tank attack" has a nice photo of a 155mm airburst over an early M1 tank, which as I understand remained operational.

For interested parties, the ATF forum on warfarehq currently carries discussions about the artillery model. The author of ATF is an US artillery officer.

http://www.warfarehq.com/forums/forumdisplay.php?f=20

[flamingknives]

Modern rounds from 5.56mm assault rifles penetrate sides and rear of the older Russian APCs just fine. Full-size 7.62 (MGs, sniper rifles) would have less problems and can also harm sides and rear of BMPs. A M113 is certainly vulnerable to full-size 7.62 rounds.

Older Russian APCs would be something like the BTR-152s?

The 7.62, is that ball or AP? I assume you mean 7.62x51mm NATO.

What ranges?

[Redwolf]

Namely BTR-80 and derivates which have down to 7mm armor.

The TacOps mailing list had that discussion recently, with people who actually fired G3s at BMPs (not BTRs) at point-black and penetrated (a reunion with a half-country with Russian equipment provides for some interesting test objects). I don't have additional information about the ammunition in use.