How effective were ground attack aircraft against armor and other hardened land targets

[tyrodtom]

When you look at pictures of WW2 tanks taken when they were in use, you'll notice the ones that have fenders, seldom have unmangled fenders.

 

[swampyankee]

I hadn't thought of that. Quite a few of the photos I've seen of tanks, ostensibly in or near action, during the WWII era show the commanders exposed from about the waist up; the drivers seem to be somewhat less exposed (for one thing, if the aircraft are coming from behind, the drivers will be shielded by the turret). Even German officers were vulnerable to rifle-caliber machine gun rounds, and an injured or dead tank commander would take that tank out of action for at least a few minutes.

 

[Ascent]

If you knew rocket firing aircraft was around would you want to stay in your tank? The chance of hitting may be low but you do know if you are hit that's the end of it.

 

[pbehn]

If you knew rocket firing aircraft was around would you want to stay in your tank? The chance of hitting may be low but you do know if you are hit that's the end of it.

I think there were many "issues" at play. Tanks attacked by Typhoons (and other rocket carrying aircraft) were not only attacked by rockets but the whole area was strafed by cannon and heavy MGs by planes on a cab rank system. I think tank crews knew they were sort of safe inside their tank from air attack but they also knew that they were the only people who were, all other infantry and soft skinned vehicles were probably gone. If you are not confident that your people are around your tank you are scared to open any hatch.

 

[Greyman]

A reasonable summation from "Air Power at the Battlefront: Allied Close Air Support in Europe 1943-45";

The retreat to the Seine clearly reveals the limitations of Allied air-to-ground weapons against tanks, particularly the 3-inch rocket. Only ten out of 301 tanks and SP guns examined, and three out of 87 armoured troop carriers examined, were found to have been destroyed by this weapon -- these figures must be compared with the 222 claims of armour destruction made by Typhoon pilots alone. In contrast is the marked effectiveness of cannon and machine guns, and to a lesser extent bombs, against soft-skin transport vehicles. By destroying large numbers of these, thus blocking roads and increasing congestion, the fighter-bombers indirectly caused the abandonment of many tanks.​

​

Moreover, many of the tanks and SP guns were found abandoned without petrol, not least because trucks carrying their fuel had been shot up from the air. German prisoners described how the threat of air attack restricted movement to the hours of darkness until congestion and haste compelled movement by day. They also told how whenever aircraft appeared crews stopped to take cover and vehicles were driven off main roads into the side roads which in turn became blocked. In effect, the almost continuous fighter-bomber attacks in daylight, within a restricted area upon retreating troops, caused a great deal of demoralisation and delay which prevented many tanks and vehicles escaping.​

And to the point of remaining in the tank under air attack, from an ORS report on fighter-bomber attack in Normandy;

Interrogation of prisoners has shown without question that German tank crews are extremely frightened of attacks by RP ... Crews are very aware that if an RP does hit a tank, their chances of survival are small. It is admitted that the chances of a direct hit are slight; nevertheless this would hardly be appreciated by a crew whose first thought would be of the disastrous results if a hit were obtained. ...​

​

The experienced crews stated that when attacked from the air they remained in their tanks which had no more than superficial damage (cannon strikes or near misses from bombs). They had great difficulty in preventing inexperienced men from bailing out when our aircraft attacked.​

 

[Shortround6]

On this subject we are quickly getting into area of weapons vs aircraft carrying them.

By that I mean if, for instance, a 500lb has a certain radius at which it will "kill" tank X then how important is it which plane dropped the bomb?
The Plane's only importance is if can deliver the bomb with significantly more accuracy than than another airplane.
Which is the better anti-tank aircraft, A Bristol Blenheim with two 500lb bombs or a Typhoon with two 500lb bombs as an extreme example?

The Germans (and the Russians) used cassette bombs or cluster bombs to drop a large number of anti-tank bomblets over a wide area inorder to make up for the lack of accuracy of the big bombs, again how important to killing the tank is the type of aircraft?

Type of aircraft is important for the survival of the aircraft crew against the defences the enemy tank force as a whole (most tanks had pretty lousy AA defences aside from their armor) could bring to bear, AA guns and general defensive fighter sweeps.

Many specialized anti-tank aircraft were never made in large enough numbers to really affect combat operations (large gun JU-88s fall in this catagory, lots of prototype/small production batches and much loved by modellers but overall effect on the eastern front was negligible )
this version

The JU-88P-3 seems to have been made in the most numbers but it was issued to 5 night attack staffels. Trying to shoot individual tanks at night?

The Germans, and to a lesser extent the British and Americans ran into a problem with specialized ammo for aircraft tank busters. There was only so much wolfram (tungsten-carbide) to go around to be effective most aircraft guns needed the tungsten cored projectiles. The Germans continued to make tungsten cored projectiles for the tank buster aircraft for a while after they banned the production of such projectiles for most other AT guns.
For the Allies I don't know how wide scale the issue of cored projectiles was for aircraft guns, we do know that Shermans with 76mm guns and M-10 tank destroyers only had 2 to 5 rounds of cored ammo in their official loadouts (and due to supply problems often didn't have that much) 75mm Shermans never got cored ammo, so it appears the the allies didn't have a lot of extra tungsten carbide.

 

[Dimlee]

Soviet sources claim the Il-2's knocked out almost 300 tanks at Kursk, 70 from the 9th Panzer Division alone. But German armor afficionadoes claim Il-2s only destroyed a few tanks and most losses were actually to AT-guns, tanks, tank traps, mechanical breakdowns and getting stuck.

Soviet tests have supported those claims long time ago when most afficionadoes were not born yet.
Il-2s just did not have the weapon which could be both accurate and lethal enough against German tanks in 1943. Except (probably) PTAB bombs but they required good skills, narrow envelope of altitude and speed and low intense AAA. Something similar to torpedo bombers, especially with torpedoes of early designs. And period of effective usage of PTABs was rather limited since Germans quickly developed counter measures.
Rockets were terrible in accuracy and were considered by pilots as a weapon for application against "areas", not against single targets. Probability to hit (not to destroy) Pz.III was:
0.08 - 4 RS-82, distance 300 m, diving angle 30 degrees;
0.25 - 8 RS-82, same distance and angle.
RS-132 and ROFS-132 could disable a tank with near (up to 1.5 m) hit but their accuracy was lower than of RS-82.
Bombs other than PTAB were even worse. And 400 kg was typical loadout.
Accuracy could be achieved with steeper dives but 30 degrees remained maximum safe angle until 1945. Anything higher and Il-2 became too unstable.
As for 23 mm cannons - accuracy of the best test pilot was 7.4% vs single tank and 9.5% vs tank column.
37 mm were more demanding. Probability to hit the target in one attack: Pz.IV - 0.04 to 0.07, SdKfz 251 - 0.08 to 0.17. It was not accidental that this cannon was phased out quickly, just after 7-8 months.
All above mentioned results were achieved not in the combat but on the firing range during the tests conducted by Research Institute of VVS. The institute recommended to create special anti-tank squadrons with highly trained pilots as the most effective measure to turn Il-2 into "anti-tank weapon". That recommendations was ignored by VVS.
Coming back to Kursk Battle... Average life of Il-2 during the first 5 days was 6(six) flights. Most of pilots did not have combat experience before. What kind of accuracy they could achieve under such harsh circumstances, we can only wonder...

Sources: Oleg Rastrenin and Vladimir Perov, authors of probably the most complete books about Il-2.

 

[Dimlee]

Highly recommended:
Survey of Allied tank casualties in World War II :: Printed Materials - USAHEC

The name is a bit misleading as there is data about German tank casualties as well.

 

[Greyman]

Great info. The VVS figures seem to agree with a quote from "Flying Guns - World War 2" by Tony Williams and Emmanuel Gustin:

"The success rates for ground attack planes were strongly determined by pilot skill, with good shots being about twice as effective as average pilots. The Soviets concluded that to ensure the destruction of tank targets, four or five Il-2s needed to attack a light tank, but twelve to fifteen were needed against a medium tank."​

Also a great bit of data from the posted survey re: Luftwaffe vs. tanks in the Battle of France.

 

[Dimlee]

In contrast is the marked effectiveness of cannon and machine guns, and to a lesser extent bombs, against soft-skin transport vehicles. By destroying large numbers of these, thus blocking roads and increasing congestion, the fighter-bombers indirectly caused the abandonment of many tanks.

Very important quote.
In my opinion, too many if not most of those stories about "tank busters" are based not on hard data but on anecdotal evidence, propaganda, etc. Probably the "wow" factor plays significant role. Turrets of T-34 flying in the air, Tigers "killed" by 12.7 mm bullets, columns of Panthers destroyed by tiny PTAB bombs in one go... wow, so cool.
Ironically, real and tangible results as disruptions of logistics chains are left unnoticed so often. Tanks will not go far without fuel and spares delayed due to congestion or because the trucks were hit. And without the infantry which was dispersed and left without vehicles to follow the tanks.

 

[wuzak]

There was only so much wolfram (tungsten-carbide) to go around

Wolfram is Tungsten, not Tungsten-Carbide.

Tungsten Carbide is a compound of Tungsten and Carbon.

 

[Shortround6]

Wolfram is Tungsten, not Tungsten-Carbide.

Tungsten Carbide is a compound of Tungsten and Carbon.

Thank you.

Many authors don't seem to know the difference or leave off the word Carbide when referring to the ammo. Tungsten alloys and/or tungsten-carbide was in great demand for cutting tools in the machine tool industry, it permitted higher speed machining with greater depth cuts and greatly reduced machine time for a given part and quality of finish over normal tool steels.

 

[AlfaKiloSierra]

I am surprised how the Typhoon got as many votes as the P-47, despite significantly inferior in armor and weaponry. The only rockets the Typhoon can get is the RP-3, but the P-47 could use 5" HVAR.

I'm not sure what it is like irl, but in War Thunder and Il-2 games, the RP-3 is extremely inaccurate and the HVAR is close to dead-on if aimed properly.

 

[Shortround6]

I am surprised how the Typhoon got as many votes as the P-47, despite significantly inferior in armor and weaponry. The only rockets the Typhoon can get is the RP-3, but the P-47 could use 5" HVAR.

I'm not sure what it is like irl, but in War Thunder and Il-2 games, the RP-3 is extremely inaccurate and the HVAR is close to dead-on if aimed properly.

part of it is timing, the RP-3 was available for several years First used in the Western Desert. The HVAR was a navy rocket developed from the FFAR and was only rushed into service by the USAAF after D-Day. It took quite a while to really take over from the M8 rocket used in the triple tube launchers.

 

[The Basket]

Wolfram is the German name for Tungsten or Tungsten is the English name for Wolfram.
It was considered a vital war strategic material and came from Spain or Portugal.
So plenty to read on how tungsten got to Nazi Germany from Spain. And how the allies did everything to stop this trade.

Very important that such minor aspects such as keeping Franco and Salazar on side was a bigger war winner as actual battles.

Tungsten was used for metal cutting and as a penetrator so very much a war material.

The tungsten trade was not cut with Spain until France was no longer occupied so late 44. The allies bought as much tungsten ore from Spain as possible so they didn't sell it to Germany.

 

[The Basket]

War is not always about tanks destroyed but if you can stop tanks moving due to threat of air power then that's plenty.

Plenty of soft skinned vehicles are just as important as tanks and 20mm cannon shells will rip them to shreds.

 

[Schweik]

Hey guys, been out of town all weekend at a martial arts tournament and doing a history presentation (very different era though!).

Some good points made here and at least one new (for me) data source that I still need to look at. I can certainly see the merit of the argument that the most telling effects of tactical air support was against those highly vulnerable soft skinned vehicles and logistics infrastructure, that disruption was often the real goal, that rockets were very inaccurate, and that tanks were tough and so on. We all know that. However I think maybe we are pushing the pendulum too far in one direction with regard to the efficacy of CAS against armor per se.

I don't have time to plunge deeply into this (yet) but I wanted to make a couple of quick points.

• Not every tank was a Tiger or a T-34/85, or even a Sherman or Pz IV.
• There were many open-topped armored vehicles of substantial importance and / or ubiquity on the battlefield. For the Germans the early tank hunters like the Marder and the Panzerjäger I, and later war behemoths like the Nashorn, the self propelled guns like the Wespe and the Hummel, and many armored cars were open topped (side armor on the Wespe was also down to 5mm). For the Americans similarly the M3 GMC, M10 GMC and that whole family of tank destroyers, plus the M7 priest and the similar British Sexton. The Soviets Su-76. Almost all the AAA vehicles too of course, and all the halftracks on every side*. Any open topped vehicle is going to be extremely vulnerable to hits from HMG or 20mm cannon.
• Not all 'Medium' level tanks or armored vehicles that did have armored tops were heavily protected on the tops and rear either - the StuGG III, one of the most important and ubiquitous German AFV's had armor down to 16mm even late in the war. The British Cruiser A-13 had armor down to 6mm, same for the Soviet BT-7. I don't think it's beyond conceivable that 12.7mm MG or 20mm cannon can bust these up. And no, a single 12.7mm bullet piercing armored bottom or top or engine compartment may not wreck the vehicle but it's dangerous as hell to be inside if it does and each hit poses a severe risk to crew and kit. I don't know if you have ever seen forensic photos of what happens when a couple of HMG rounds hit an occupied vehicle but it is not pretty.
• More to the point, it's certainly not inconceivable that the 23mm guns on an Il-2 or shaped charge bomblets, or 37mm guns used on a variety of CAS aircraft can destroy some of the heavier and better protected tanks and other armored vehicles.
• While say, 5-8% hits per strafing attempt may not sound like much, keep in mind thousands and thousands of sorties were flown. If and when the local AAA was neutralized, and fighter escort adequate, strafing Il-2s, Ju-87D (with 20mm cannon), and P-47s could do several strafing runs before retiring. If you had say two squadrons flying out of a cab rank or 'circle of death' to make 3 or 4 strafing runs each, that's 60 - 100 attacks, which statistically means probably at least a few hits for each mission. When you consider this is repeating almost every day, and even multiple times a day in some Theaters and during some battles, to me that adds up to a lot of heavy bullets smacking into AFV's on a pretty regular basis whenever they were caught exposed. Anecdotally, the cannon were the most effective weapons of the Il-2, not the bombs or rockets. And while anecdotes can be wrong I'm not sure it's safe to assume they were always wrong.
• For dive bombing in particular, I again remind everyone that we know for a fact that dive bombers could hit relatively small ships like troop transports, cruisers and destroyers. If dive bombers can hit the Shintai Maru No. 4 with a 6 meter beam, then dive bombers can hit a column of tanks driving down a road in Libya or Ukraine and land bombs close enough to kill them even if it was a Tiger or a KV.
• Tungsten / Wolfram also may be basis of the best AP ammo in WW2 but it was hardly the only AP ammo. Steel core bullets penetrated pretty well too, even steel shelled ones. The 23mm VYa of the Il-2 could punch through 25mm of steel plate at 400 meters. Even the 20mm ShVAK and 12.7mm DShK could penetrate 15mm armor at 30 degrees at short range and 20mm plate specifically on a Pz IV at 20- degrees (~150m).
• We shouldn't, I don't think, assume that the performance of every type of ground attack aircraft was identical through the war. I think that is the crux of the issue. What P-47s could do against late model German Panzers in autumn of 1944 may not reflect realities at Stalingrad or El Alamein or Arras. Maybe that is the pattern maybe it isn't - it's probably worth finding a bit more data before reaching firm conclusions. That was the point of the thread - to expose more data.

By the way, I forgot who commented "if 20mm guns could take out tanks they would have given them to infantry" or something along those lines... they did, actually, give them to infantry see the AT rifle, quite ubiquitous in the early war (and somewhat effective, notably in the hands of the Finns), and it was also the main armament of numerous armored vehicles again especially in the early war - Pz II, the T-60 etc.. In say 1940-41 the larger tank armament was usually in the realm of 37-50mm and that was meant to punch through frontal armor of rival tanks. 20mm was more than enough to destroy many lighter armored vehicles.

*There is a Soviet report on German tank armor showing that side armor of light armored cars and APC's (halftracks?) could be penetrated at 250-400m by DShK 12.7mm and ShVAK 20mm (which had similar penetration). This is the image from document "CAMD RF 38-11355-778" showing penetration and angles, also recommended as guidelines for T-60 and other Soviet AFV's with 20mm armament.

 

[Schweik]

I think we have an idea in modern times of CAS efficacy based on precision munitions and laser guided or JDAM bombs and so forth, but that is a bit of a distortion (even the modern stuff isn't as great as the way it's sold to be) and WW2 obviously worked on a different and you might say far more iterative level. It would take multiple attacks even with what passed for precision CAS back then to neutralize a target. That is why they made so many Stukas and Il-2s

 

[The Basket]

Lahti and Boys anti tank rifles were certainly a thing but quickly outdated by the end of ww2.

But AP is velocity based so been able to penetrate armour at 100 yards is no good if I have to be 100 yards away carrying a chuffing great big heavy gun shooting away at a tank!

Anti tank guns were unable to be up gunned otherwise you would take the shoulder off any shooter so RPG and Carl Gustav is the way forward. The bolt action AT gun that could go through a Tiger would be quite the beast.

If you think about it, the 75mm gun on the Sherman had problems with the Tiger so good luck with a fighter bomber shooting 20mm.

 

[Schweik]

This is one of the things that makes the beginning, middle and the end of the war different.