Since nobody knew what 'full bottom rudder' meant, I found this info:

A skid is an uncoordinated maneuver occurring when the pilot uses too much rudder input in the direction of the turn. Another way to say that is the pilot uses too much “bottom rudder.”

Aviar

I think that corroborates the idea mentioned about it being a type of snap roll.

And that's why I would rate it as desperate. The risk of totally losing control is there. And its desperate because in the faster less maneuverable plane you should not be in that pilots position.

The interesting question (and initial one) is, what happens, if you give too much ruder in direction of the turning - in Il-2?

In the direction of turn? Nothing much really. It kind of hits a likit and then the plane may, depend on the type, stall and sometimes flops out of a turn. The interesting bit is when you slam counter rudder while rolling into a skid. In many planes, P-51 included, you can get a negative torque roll that is very difficult to follow. I use it to evade attacks online. Only partially effective as it bleeds a tom of speed.

Especially in a P-39.

I once saw a documentary on a WW2 battle and it started with the offical, documented weather reports from both sides on the day of the battle. Both were in agreement that it was overcast with occasional rain. Note that this was the report, not the forecast. They then asked all veterans interviewed for that show how they remembered the weather, they averaged out on sunny with some clouds, each being different from each other. Imho this was a perfect illustration how memory and facts can differ when it comes to detail.

I don't think that the documentaries are a bad thing. I like to listen to the people telling what they experienced, first had accounts are almost always worth the time spent listening. Also, for the casual viewer, it is this kind of show that generates interest in the WW2 flight sim genre. Better to have some facts wrong about the air war in WW2, then to not know that there was an air war at all.

The Il-2 Mustang is not all that comparable to the real thing in the context of the sim. I have to agree that it is very accurate on a one to one scale to the real Mustang, given the constraints of the game engine, but compared to the other aircraft depicted in the simulation, it is way too touchy to trim and control. If we were talking pictures, the Mustang is photo-real while the other (especially Axis) aircraft are done in a graphic novel style. Part of this may be due to what I perceive as the way the game was optimized for Force feedback sticks, but the Mustang's notoriously light stick forces should result in much less demand for re-trimming at the slightest change in airspeed or AOA, not more.

Compare it to the P-40, which is also in the game. The P-40 in real life is always referred to as a handful; the pilot has to be alert and ahead of the aircraft at all times and the rudder trim wheel is constantly in play. America's Hundred thousand devotes several paragraphs to the section about trimming the P-40, and makes it clear that trimming every other aircraft in the US inventory was quite easy (and predictable) by comparison.

Let's remember that the P-40 was basically a P-36 with an inline Allison crammed onto its nose. It was a compromise design. The Mustang, designed almost five years after the basic design for the P-36/40 series was completed, was a much more refined and tractable aircraft. It should have been, given that its design was targeted at out-performing the P-40 with the same basic engine. 'Bumping it up' to the (also) inline Merlin was a much less traumatic surgery than replacing a radial engine with a heavier inline powerplant; the Merlin powered Ponies needed more minding in some respects, but the consensus was that it was still much more easily trimmed than any model of the Hawk 81/87 series, and generally more ...predictable, if not quite as 'slam-bang' at low speed aerobatics.

The P-40 in the game is much easier to trim and fly accurately than the Mustang, which is simply turning the historical record on its head; most pilots who flew the Mustang in combat also flew either the P-39 or the P-40 in training or earlier combat tours, and all of them report that the Mustang was better in every way that mattered--it was easier to fly, not just faster, better at higher alts and longer ranged.

This is particularly egregious when we remember that the Soviets got a few thousand Lend-Lease Warhawks and thoroughly tested & documented examples of every sub-type at TsAGI, which Oleg and his team used as their primary source of flight data for most of the aircraft initially depicted in the sim. One can only assume that the P-39 and P-40 are accurately depicted compared to the other aircraft of that era modeled in the sim, that their faults and strengths are in proper proportion to those of the Bf 109F/G, the FW 190A and the Japanese fighters. The Mustang and most of the late-war US fighters are not. You can claim that they are more accurate in comparison to the real aircraft using recent data from actual flying examples, but it is a bit silly to claim that they are accurate in comparison to aircraft that have not been flown and measured in 70 years.

You can de-bunk and question the memories of an old man, but he was there, doing things that 99 out of a hundred of us could never do on the best days of our lives. Maybe, just maybe, there is a bit of truth in what he was saying.

cheers

horseback

With respect... I don't think any of us are going to say that this was a fabrication or a lie or anything like that. But human memory is notoriously unreliable... I'd rather go with the test results and that type of more objective (it's not 100% here) than some crazy move that a veteran pulled, that worked (again, no denying that), as the basis for a FM change. There isn't anything to go on there anyways...

What you say about the P-40/P-51 trim thing is true. I've heard the P-40 required a lot of trim to get it right while the P-51 was easier in this regard. Test pilot and combat pilot reports corroborate that. So it's not 100% right in the sim... definitely not. But I've looked over data long and hard and I'm not sure what's wrong either. The other thing that you'll notice is that 4.12 features an updated FM for the P-40 and some of that trim stuff will probably come into play.

IIRC there were quite a few pilots that did not like the P-51 better than the P-40 or P-39. And didn't 56th FG willingly fly P-47 because they liked them more than the P-51?
And didn't -I think- Bud Anderson state that the P-51 required trim adjustment all through the whole flight?

The P-39 though does require constant trim change in this game. The Bf 109 supposedly does not require much trim change -as it has no adjustable rudder and aileron trim -it was designed that way.

The P-40 in this game does not require trim change as much as it should need IMHO. And it is a extremly stable gunnnery platform, maybe a bit too stable.
Just speculation, but maybe the non-changing CoG could give rise to this behaviour?

And yes I do think the plane models -even the late war US fighters- are fairly accurate and compare well to each other. This sim doesn't just give them the accurate historic context. Range and good serviceability don't count. Pilot quality is the same in the Axis and Allied camp while in real life at the time where the Mustang ruled the skies on average an Axis pilot was less capable than an US pilot. And US forces used superior tactics many times, trying to attack from favorable positions, trying to bring numerical superiority, and trying to cover each other.

Had the US in the late war faced an enemy that could bring equal numbers of planes with enough fuel and equally capable pilots, using the same tactics the US did(reflecting the situation in this sim), they would have suffered considerably.