fw 190a5 flight model

[K_Freddie]

So, aerodynamic maths explain 100% of flight, a 100% of the time and the pilot's always wrong, according to the 'propellor head' on the ground.

You sound like an aircraft crash investigator out to needle the pilot, as they usually do. Not that they always wrong, but they not always right and in this situation not likely to accept this.

[JtD]

Originally Posted by K_Freddie

So, aerodynamic maths explain 100% of flight, a 100% of the time and the pilot's always wrong, according to the 'propellor head' on the ground.

I gave it a 5% margin.

[K_Freddie]

I was thinking up to 10%, which is why I'll allow Gaston's argument.

I'm well aware of the manuals and their contents, the pilot errors, etc...
While not being a Mech/Aerodynamic engineer, I do work in the engineering field.. some 34 years of it, some on aircraft and some pilot time. So I am no stranger theory, formulae and modelling.. as well as the practical side, plus all the goodies that go with it.

Putting this all together, I'm not going to rule out Gaston 100%.

[Janosch]

Just one more thing, said Columbo. What about computer games besides Il-2? It seems that Fw-190 made first appearance in Secret Weapons of the Luftwaffe (1991) (I can do research too, ha ha ha), and it wasn't a great turnfighter there, and so it has been ever since in all games to follow. Do you guys think that the all of the game designers who put 190 in their games did their research wrong?

[K_Freddie]

It's like Stats.. you see what you want to see.
Before IL2 came out not many (in the west) knew that there was a war on the eastern front, never mind a tank busting machine like the IL2, I mean the P51 won the war.

I at the time believed all that 'research' too, but Oleg opened our eyes.
Now I'm a bit wiser about being too judgmental.

[Oryx]

Wow, I haven't posted about Il-2 for a very long time, but just cannot resist with a comment like the one below:

Originally Posted by K_Freddie

So, aerodynamic maths explain 100% of flight, a 100% of the time

Actually, it does. For the simple reason that flight is described "perfectly" by the laws of physics. There are no exceptions. At least, in many years of flight testing from inside the aircraft and from a telemetry station on the ground, I have yet to see a single case of an aircraft defying the laws of physics. Also, today the knowledge surrounding the various factors that contribute to the forces acting on the aircraft are very well understood and can be modelled very accurately - at least accurate enough that the prediction models get extremely close to the measured ones.

When it comes to flight simulation, however, the programmers must strike a balance between fidelity and practicality. The most difficult part is not to model the kinematics - the equations are quite simple - but to generate the data to populate the models. To generate this data is both time consuming and costly. I have worked with simulators where the fidelity was so high, that we would sometimes only use spot checks in actual flight to confirm the simulator predictions. However, to achieve that level of fidelity took wind tunnel tests, numerical predictions (such as CFD) and also in-flight systems identification. The costs are obviously staggering to create such a model. This is not feasible for a game, especially ones where more than one aircraft needs to be modelled, so developers have to make some decisions on how far to go in the modelling process. The result will always be a compromise. It doesn't mean there are some voodoo aerodynamic effects going on that engineers don't understand.

and the pilot's always wrong, according to the 'propellor head' on the ground.

I don't think it is one or the other: I often rely on test pilot comments during testing. However, what is very true and I think both you and Gaston seem to miss, is that the combat environment is probably the worst possible time to compare aircraft performance. There are just too many things going on to make any quantitative judgement, unless the differences between the aircraft are really large, such as a jet vs a piston-prop. For example, does the other guy really have a faster aircraft, or did he just start the fight slightly higher and was able to build up some energy into the merge? Or does he really turn better or is the fight just happening closer to his corner speed than yours? Half the time, you won't even remember your own configuration during the fight (speed, height, throttle settings, etc), let alone what the other guy was doing. Even if one aircraft type consistently outperformed another on a certain aspect during combat, the reason might very well still lie with better tactics rather than a true performance advantage.

I say the above with utmost respect to fighter pilots with whom I have also worked extensively. I have seen clearly inferior aircraft consistently beat superior aircraft in mock combat when the pilot in the inferior aircraft was experienced, especially when he was experienced in both types. An example that I have seen with my own eyes were fights between fighter trainers and front-line fighters, where instructors in the trainers could consistently give rookies in the front-line fighters a hard time. I bet some of those rookies were thinking to themselves that their mounts were not nearly as good as advertised, while in reality the instructors just understood better how to exploit the strengths and weaknesses of the two types.

Somewhere earlier in the thread I think Gaston referred to "canned tests". Yes, that is exactly what one has to do during flight tests to determine the true potential of the aircraft. The only way to really know is to isolate parameters one by one and then test them. Combat is not the time to measure what the aircraft can do - combat is the time to put that knowledge to use.

By the way, flight testing is about much more than performance - I have spent much more time on flying qualities and handling qualities testing than performance testing. Handling qualities are extremely important when the question comes up on whether you can consistently extract the maximum potential out of the aircraft. Yet, on gaming simulations the topic of handling qualities seldom come up as few people know how to measure and interpret them. Of course, these days even more time is spent on avionics and systems testing, but that is another topic.

A small final comment before I let you guys be. I honestly don't have the time or energy to comment on every point made by Gaston, but this one really stood out:

Originally Posted by Gaston

My note: horizontal combat was never considered outdated in all of WWII, except for the Allies in the Pacific: It covers about 95%+ of all Western air battle in 1944

This is simply not true. There were many dogfights in WWII and many did indeed end up in horizontal combat. In fact, I bet the natural reaction when bounced is to turn. However, attacking from superior height was the preferred method for just about everyone and it remains so today. Horizontal combat (in fact, dogfighting in general) is always a gamble - you may or may not win depending on the relative skill of your oponent. Attacking from superior height gives the attacker an "unfair" advantage, even if he has an inferior aircraft. Entering a fight with the plan to immediately enter horizontal combat is never a good idea. Only once the fight developes into a dogfight might a pilot with an aircraft with known good turning performance prefer to stay in the horizontal. The most consistent results always came from attacking using an energy advantage (height or speed) and then to get the victim on the first pass, ideally without him ever seeing you and without letting a "dogfight" develop - and this is exactly what accounted for the majority of aerial kills in WWII.

[IceFire]

Oryx: Agreed, that comment does stand out and it's in stark contrast to any volume of reading on WWII air combat on nearly all fronts of the war.

I love this quote from a Russian pilot in particular:

Q: Could you describe ordinary dogfight?
I can’t understand the question… There were no dogfights. You saw an airplane, approach it from behind, attack and leave. Bombers were not advised to attack from straight behind – the gunner would get you. Better attack it from behind-low, with an angle 20-30 degrees. Take lead and fire your weapons.
On the other hand over Kuban it was always cloudy, enemy would suddenly appear out of the clouds in front of you… And you just press the button… Single shot. I do not remember a single case when there would be a “dogfight”. Speed and maneuver is everything!

http://mig3.sovietwarplanes.com/pilo...in/zyvagin.htm

This would not be an isolated comment either. It's not to say that dogfights didn't happen but they are much romanticized I think.

[Herra Tohtori]

Originally Posted by K_Freddie

So, aerodynamic maths explain 100% of flight, a 100% of the time and the pilot's always wrong, according to the 'propellor head' on the ground.

Aerodynamics as a science explains the flight characteristics of any aircraft with excellent precision.

Simulators are a different thing. Not only is the performance and handling characteristics always an approximation to some degree, the amount of things simulated may affect the actual combat performance of the aircraft.

For example, if you choose to fly with wonderwoman view, the visibility (cockpit design) ceases to be a factor, which gives a lot of advantage to planes such as F4U, Bf-109, and many others. When you restrict views to cockpit view only, planes with better visibility suddenly become a lot more effective in combat because the pilot can maintain their situational awareness better.

This is an example of a factor affecting combat performance in simulator, without having any difference in hard aerodynamic performance.

Similar example would be the thing I mentioned earlier: Handling qualities, control forces required to maneuver the aircraft, things that the simulation can only approximate to some degree based on some data. How hard can a pilot deflect ailerons in A6M Zero flying at 500 km/h? How hard is it to actually turn a Bf-109 diving at 650 km/h?

In other words, while simulators can usually be very accurate with the aerodynamic performance modeling, the combat performance of aircraft in virtual sky doesn't necessarily fully take into account the other things that were a definite factor in real life. Pilot skill, physical condition, fatigue level, tactical situation in majority of engagements, tactics that are used, fabrication differences between individual planes, visibility from the cockpit - none of this is usually even discussed when we're comparing aircraft performance.


The notion that any combat pilot with any practical experience (bar the very beginning of the war) would have voluntarily offered fight in horizontal plane if their plane was faster than the other is quite amusing. Even if your plane has better turn radius and turn rate, you would still want to retain all the energy you can in case the bandit's friends pop up when you're working on them.

Losing your energy puts you in more vulnerable position, no matter what your aircraft can do.

[MaxGunz]

Originally Posted by Herra Tohtori

Similar example would be the thing I mentioned earlier: Handling qualities, control forces required to maneuver the aircraft, things that the simulation can only approximate to some degree based on some data. How hard can a pilot deflect ailerons in A6M Zero flying at 500 km/h? How hard is it to actually turn a Bf-109 diving at 650 km/h?

Oleg did model stick forces along with trim. IL2 pilots are restricted to 20 kg strength for game considerations, possibly because fatigue modeling was too much code. The IL-2 stick interface is strength based, how far you move your joystick modified by your stick settings says how much strength the virtual pilot applies to the virtual stick. And trim affects the virtual back forces (from control surfaces) that IL-2 does model. Oleg having been a test pilot did have ideas he wanted in his sim.