Soviet aircraft the west coulda/shoulda used?

[FLYBOYJ]

It's not has the bearing of anything, it's just a question of the utmost performance in armor piercing matters. So you'll never pierce a safe with a flashball or with a wood-drill. With weight and velocity, of coarse you can just brake it, by craking it. It's not the same thing.

VG

It depends on the hardness and thickness of the armor you're trying to pierce. The Harder the plate the more brittle it becomes when you put a direct load to it in an unsupported area. If the penetrating material has a correlating harness to the the surface trying to be penetrated as well as the right shape at the tip, then the right amount of force behind it will do the rest. I could take a cone or sharpened shaped steel object with a Rockwell harness of say C40 and with enough force penetrate a plate with a hardness of say C60 if the thickness of the plate cannot sustain the load behind the object. The object doing the penetrating may distort, crack or break as you put it, but it will penetrate the plate if the thickness AND brittleness of the plate can't support the dynamic load of the object being forced (or fired) at it.

 

[Tzaw1]

According Boyevaya rabota sovietskoj i niemietskoj aviacii w Vielikoy otechestviennoy voynie (The figtning work of Soviet and German aviation in Great Patriotic war) by Andrey Smirnow, Moscow 2006, pp. 291-292.

Penetration of Il-2's armour

For MG 151/15
12 mm back plate: AP 400 m at angle above 50°, HE 100 m above 60°
6 mm plates: AP 400 m above 20°, HE 100 m above 30°

For MG 151/20
4 mm plates: HE 600 m

At drawing below: armour thickness in mm (from Kuznetsov's monography)

BTW:
1. Oil radiator wasn't armoured from the back (this is note for Hartmann).
2. Many of Il-2's had a wooden rear part of hull and wings.

And a small general remark:

This was the Russian tank, for Russian army and Russian industry, to a maximum adapted to our conditions of the production and the exploitation. And fight on him could only Russians!

Such opinion, maybe slightly exaggerated, Mikhail Bariatynski put out to the tankT-34. You can use this to the most (if not all) of Soviet planes.

 

[GrauGeist]

Great illustration of the IL-2's armor...

One thing I notice though, is the lack of armor for the rear gunner. Am I missing something here, or is that position left exposed?

 

[Colin1]

Great illustration of the IL-2's armor...

One thing I notice though, is the lack of armor for the rear gunner. Am I missing something here, or is that position left exposed?

I can also see what German pilots meant by hitting the Il-2 in the 'armpit'; definitely looks like a way in there

 

[Condora]

I guess the poor rear gunner was "additional anti-shrappnel armour"...

 

[drgondog]

Geodesic.
Wonder if that kind of construction could be used on a fighter...
Large "holes" in the structure (bomb bay, e.g.) made it weaker, but a fighter doesn't have them.

No. Fighters are stressed 2.5-3 x over bomber design loads.

What that means is that metal skin with shear capability (aluminum, steel) is required to transmit bending loads to stringers via shear panels and torsion via bulkhead/skin combinations. A geodesic structure Might work but everything must be carried in combination of truss like tension/compression with no provision for shear panel distribution - as linen is inadequate.

 

[drgondog]

Great illustration of the IL-2's armor...

One thing I notice though, is the lack of armor for the rear gunner. Am I missing something here, or is that position left exposed?

Dave - I believe the pilot and engine is essential to the mission and most threats are coming from the targets out in front and sides. The plate in the rear provides some protection to Gunner, but Gunner/plate combo great for pilot from rear attacks - lOl.

 

[Condora]

No. Fighters are stressed 2.5-3 x over bomber design loads.

What that means is that metal skin with shear capability (aluminum, steel) is required to transmit bending loads to stringers via shear panels and torsion via bulkhead/skin combinations. A geodesic structure Might work but everything must be carried in combination of truss like tension/compression with no provision for shear panel distribution - as linen is inadequate.

I'm outta my depth here... señor, mee beezeeness ees computors!

But not all airplanes were dependent of that system - monocoque/stressed skin? -, at least the Hurricane still used fabric, right? What would be the problems of replacing linen with something else?

 

[Tzaw1]

at least the Hurricane still used fabric, right? What would be the problems of replacing linen with something else?

None. Example - Yaks. The last Yaks are covered with aluminium sheets. But it was still non-working coverage.

 

[DerAdlerIstGelandet]

I'm outta my depth here... señor, mee beezeeness ees computors!

But not all airplanes were dependent of that system - monocoque/stressed skin? -, at least the Hurricane still used fabric, right? What would be the problems of replacing linen with something else?

The Hurricane did have its doped fabric wings replaced by an all metal wing.

 

[Condora]

The Hurricane did have its doped fabric wings replaced by an all metal wing.

OK, but just the wings, the fuselage still was doped fabric. And even had one wing of each, sometimes...

None. Example - Yaks. The last Yaks are covered with aluminium sheets. But it was still non-working coverage.

OK, so as an intelectual exercise, take for instance a geodetic airplane covered with aluminium sheets. Advantages over monocoque/stressed skin would be... what?
Would it be some "structure resilient as Hell" airplane?
(I'm not thinking armour. Yet...)

The kind of airplane that you've used up all your ammo on it, and that "flying gruyère" is still flying?

 

[DerAdlerIstGelandet]

OK, but just the wings, the fuselage still was doped fabric. And even had one wing of each, sometimes...

The wings were interchangable, but I find it hard to believe that it would fly with one metal and one fabric wing. That would throw off the CG and the weight and balance.

 

[Condora]

The wings were interchangable, but I find it hard to believe that it would fly with one metal and one fabric wing. That would throw off the CG and the weight and balance.

Not your everyday configuration, but there was at least an aeroplane doing it, I remember reading it (for trials, if I recall correctly). How often they used that configuration, I don't know. If the difference was not too great - one can always balance the wings, and remember that one is "weaker" -, they could use an old wing to replace a new one that was heavily damaged.

If they did it in such cases, I have no indication... perhaps someone else has a clue, you guys always seem to have more data than I do.

 

[VG-33]

I can also see what German pilots meant by hitting the Il-2 in the 'armpit'; definitely looks like a way in there

What you can see it's a way for the wing spars, and schematic drawing innacuracy. All armor plates were joined (placed edge to edge) on a high tensile steel frame. Moroever armor was sometimes double, as for pilot's seat and il-2 bathtub.

VG

 

[GrauGeist]

Dave - I believe the pilot and engine is essential to the mission and most threats are coming from the targets out in front and sides. The plate in the rear provides some protection to Gunner, but Gunner/plate combo great for pilot from rear attacks - lOl.

I'll be danged...I had no idea that the IL-2's pilot was additionally sheilded by the rear gunner's body.

Makes me wonder if the stories about the rear gunners being convicts (or similiar) was really true, or was it one of those things where the Soviets sarcastically meant lack of protection for the gunner was a "death warrant".

 

[Colin1]

Makes me wonder if the stories about the rear gunners being convicts (or similiar) was really true, or was it one of those things where the Soviets sarcastically meant lack of protection for the gunner was a "death warrant".

From what I can gather of those stories
the convicts had to complete 9 combat missions to be admonished of their 'crimes against the state'
If they looked like they were going to make it, they were transferred off and into something more likely to get them killed (the mind boggles: whatever that might be)

 

[VG-33]

Hello

=Tzaw
Penetration of Il-2's armour

The way is it presented, it"s a kind of information 100% true of course, but 0% valuable:

- is it from ground tests or from air battle statistics?
- was it from 30% or 70% cases on your statistical Gauss curve? Russians always gave the both values.
- In how many cases the bathtumb boring/damaging lead to the whole plane loss?



1. Oil radiator wasn't armoured from the back (this is note for Hartmann).
False, only for very first series. I admit that pivoting armored louvres were slim (5 mm) anyway.

2. Many of Il-2's had a wooden rear part of hull and wings.
Some of them of very bad wooden parts. Well, with a TBO of 50 hours for the AM-38 engine and a life expectancy of 20-30 missions, i suppose it was not of a great importance...

Regards

VG

Such opinion, maybe slightly exaggerated, Mikhail Bariatynski put out to the tankT-34. You can use this to the most (if not all) of Soviet planes.

What do you mean?

 

[VG-33]

From what I can gather of those stories
the convicts had to complete 9 combat missions to be admonished of their 'crimes against the state'
If they looked like they were going to make it, they were transferred off and into something more likely to get them killed (the mind boggles: whatever that might be)

This is an urban legend of course, but rear gunner was realy poorly protected until the late Il-2 KSS Strelka (Arrow Wing) (Il-2 with backwards swept wings) production, with lenghtened bathtumb.
Anyway, gunner's head and shoulders reminded unprotected.

??????? ??-2 ???

Regards

 

[Tzaw1]

What you can see it's a way for the wing spars, and schematic drawing innacuracy.

This is natural inaccuracy. Because this is schematic drawing, not production.
BTW What frame? Armour was the frame. See attached image. There's been the aluminium engine mounting (numbered elements).

Moroever armor was sometimes double, as for pilot's seat and Il-2 bathtub.

There was no armour pilot's seat.

is it from ground tests or from air battle statistics?

For MG 151/15 from ground test in factory No 125, July-August 1942. I do not know no manner, to qualify from what distance was pierced armour during the fight.

In how many cases the bathtumb boring/damaging lead to the whole plane loss?

I don't know. And You?
But the reading of the monograph "Shturmovik Il-2: "Lyetayushchiy tank" by Oleg Rastrenin permits to suppose, with 100%.
BTW There is the good analysis of damages Il-2's.

Some of them of very bad wooden parts. Well, with a TBO of 50 hours for the AM-38 engine and a life expectancy of 20-30 missions, i suppose it was not of a great importance...

Surely you joke
At the all weakness of the armour, only 10% damages happened on protected elements (4% engine, 3% radiators, 3% cockpit).

the late Il-2 KSS Strelka (Arrow Wing) (Il-2 with backwards swept wings) production, with lenghtened bathtumb.

These are two separate matters. The Il-2 with a rear-gunner was in the production and service from the beginning 1943, Strelka from the end 1943. The armour himself did not change.

 

[Altea]

This is natural inaccuracy. Because this is schematic drawing, not production.
BTW What frame? Armour was the frame. See attached image. There's been the aluminium engine mounting (numbered elements).

But you only send the engine mounting scheme, not the whole armored caisson.

There was no armour pilot's seat.

It seems that there were a 12mm plate protecting pilor's neck and head, and 5mm partition between the pilot's back and the main tank.

Surely you joke
At the all weakness of the armour, only 10% damages happened on protected elements (4% engine, 3% radiators, 3% cockpit).

AFAIK, even if the AM-35A and 38 engines had successivly passed the state 100 hours trials, they were soon reduced to 50 hours of TBO (time before overhall) for serial ones. It's also an explanation for the short life expectancy of the early Il-2's.

Regards
Altea