Placing the Bell P39 Aircobra.

[Juha]

Hello Franek
I didn't claim that Il-2 was great; I only say that it was a good ground attack plane. The armoured a/c was one option with its pros and cons. But anyway it could take a lot of damage and survive and the armour seemed to give pilots confidence, which was important. And when enemy infantry learned that they usually could bring Ils down with their weapons, that at least should have lower their morale. It's alway help morale if one at least think that he can do something against a threat. On .5 Browning I should check the penetration power of its API round to make a valid quess of its lethality to Il-2 but poor Germans didn't have anything comparable.

On Cobra, after all it had only 1200hp engine, later models could use 1420hp WEP, but that was only for 5 minutes. Allisons seemed to have taken overboosting well but still there was a limit before serviceably began to suffer. If one could put better gun in nose, which IMHO may be problematic because of the a/c's sensitivy to COG changes, it would have increased weight. So IMHO there would not have been much reserve for armour weight to add, if one wanted to keep good handling and the capacity to carry 500lb bombload. After all Cobra had rather small wing. Of course there was pros also in smallness, less target area.

Only some thoughts, I don't have time to study this question deeper.

Cheers
Juha

[Franek Grabowski]

Juha, could you elaborate what constitutes a good ground attack aircraft? Perhaps this should be explained in the first place.
Concerning Cobra, the problem was with CG moving too far aft., so placing heavier armament or armour would only help. The question about available power is valid but the question is, was it necessary, and if reduction of lifetime was substantial and important in field conditions. I believe the real problem is that nobody ever considered the idea, perhaps because all the production was necessary for the USSR, and they considered them excellent fighters in the first place.

[Juha]

Hello Franek
I have time only for a short comment.
In Cobra i meant that more powerful cannon not only meant heavier cannon but also heavier ammo, which as useable load in the nose would be a problem. And IIRC radiator was behind 1/4 MAC so armour around it without some compensation would aggraviate CG problem.

Night
Juha

[Franek Grabowski]

Yes, you are correct, but heavier ammo could mean less ammo, and the CG would move forward anyway. Of course we are discussing a theoretical situation, and a rather what if and not an actual scenario.
Nonetheless it would be interesting to compare effectiveness data of both Soviets and Allies (and Germans if available) in order to check how actual ground attack aircraft performed.

[Juha]

Franek
"but heavier ammo could mean less ammo"
Of course, I was just thinking that 30 rounds was such a low number that the number of bigger ammo should have been at least 25 but after all Hurricane IID also had 30 rounds ie 15 rpg and Ju 87 G had only 12 rpg. So less ammo was a viable option.

"Nonetheless it would be interesting to compare effectiveness data of both Soviets and Allies (and Germans if available) in order to check how actual ground attack aircraft performed."

Yes, I agree.

Juha

[tcolvin]

Originally Posted by Juha

Franek

"Nonetheless it would be interesting to compare effectiveness data of both Soviets and Allies (and Germans if available) in order to check how actual ground attack aircraft performed."

Yes, I agree.

Juha

I think most would agree this is the important question.
But aircraft effectiveness depended not just on the aircraft but on the system of which the aircraft (singular and plural) is but one element.
Therefore the elements need identifying and their interrelationships quantified.
This can only be done by examining specific examples and then aggregating the values.
But the data probably do not exist. Pilot reports are usually valueless.
Considering the significant investment required for doing such an analysis for just four days for one division, and the heavy reliance placed on war diaries, personal diaries and observation, and on war correspondent reports that were luckily available on that occasion, there cannot exist many battles that could be the subject of such an analysis.
And then it is important to compare the outcomes of battles with and without close air support.
But until some of this is done at least in part, there will be no resolution of this emotive subject, or even modification of entrenched views.

Tony

[Franek Grabowski]

You put a tank on a range and you bomb it by all means until it is destroyed. Then you count warload spend and you have effectiveness. For example it was found that only a direct hit of Soviet RS-132 rocket could destroy a tank. It was found that none of 134 fired RS-132 hit the target during the test.

[tcolvin]

Originally Posted by Franek Grabowski

You put a tank on a range and you bomb it by all means until it is destroyed. Then you count warload spend and you have effectiveness. For example it was found that only a direct hit of Soviet RS-132 rocket could destroy a tank. It was found that none of 134 fired RS-132 hit the target during the test.

Well, that's exactly the same result obtained from an Operational Research analysis of rocket attacks on targets in the Breskens Pocket. 140 Rocket Projectiles had to be fired by Typhoons to give a 50% chance of hitting a Panther. But that was in battle conditions and not on a range without Flak, which was the test you are referring to. But the OR Report does not say whether the Panther was defended by Flak.
Intense Flak resulted in 2TAF refusing to attack heavily defended targets such as the Rhine bridges and Me262 landing strips. Effectiveness obtained on a range was irrelevant in such cases where it was nil. The Rhine bridges were never brought down by 2TAF, and were eventually destroyed by the Germans themselves.
In some cases Bombphoons dropped bombs under radar control through cloud. Then there was no Flak but it became a form of inefficient carpet bombing.
You have to take the system as employed on the battlefield, IMHO, and not results obtained on a range.

[Franek Grabowski]

Tony
If results achieved on a range have shown low efficiency, well actually no efficiency, in field it must have been worse. Then Typhoon attacks seem much more efficient that those of Il-2s. Or you deny the numbers.
Concerning Flak - I have already mentioned the attempt to destroy bridges in Jabłonna area in 1944. They were destroyed by bomb fitted Airacobras because Il-2s were unable to get through Flak and air defense.
I find discussion of other factors useless at this stage.

[tcolvin]

Originally Posted by Franek Grabowski

Tony
If results achieved on a range have shown low efficiency, well actually no efficiency, in field it must have been worse. Then Typhoon attacks seem much more efficient that those of Il-2s. Or you deny the numbers.

I don't deny the numbers but I deny your conclusion.

"It was found that none of 134 fired RS-132 hit the target during the test,"
while 140 Rocket Projectiles fired by Typhoon gave 50% chance of hitting a Panther.

These results are identical.

In other words if a Typhoon fired 134 rockets then it would be expected to miss because its chance of hitting is LESS than 50%. The IL-2 did miss with 134 rockets. The results are identical. Capiche?

What is shown is the inherent inaccuracy of rocket projectiles. That is what Rudel stated and what Operational Research and RAF tests showed, but what Typhoon pilots and 2TAF vehemently denied.

Conclusion: any aircraft firing a rocket was inefficient. Any organisation that knew rocket-firing was inefficient but insisted it was efficient is making a fraudulent claim. I rest my case!