Energy Maneuverability

[JG14_Josf]

Please Consider Energy Maneuverability

Before diving into the fight here I see an opportunity to introduce my axe to be ground into this fight, so as to leave less room for misunderstanding.

These Combat Flight Simulations are not new to me. The first Combat Flight Simulator I found was on the first Flight Simulator program offered by Microsoft, and it was a stick figure World War I hidden file in that program.

I went to Air Warrior, then Warbirds, then IL2, a brief look at Dawn of Flight, and now I have this Cliffs of Dover Combat Flight Simulator loaded onto an almost up to date PC.

I have been on Forums in the past, some of the regulars here may recognize my JG14_Josf username/handle.

My interest and concern has to do with accurate measures of relative performance and to that end my interest has to do with Energy Maneuverability.

Climb rates, top speeds, and sustained turn performance are distant secondary measures of Energy Maneuverability.

Please consider Energy Maneuverability.

I already checked this Forum, briefly, and I found this:

http://forum.1cpublishing.eu/showthread.php?t=34290

The basic Energy Maneuverability question has already been asked and that question is basically this:

Cornering Speed: "The lowest air speed at which a fighter can obtain the structural or aerodynamic limiting G force."

In the "dogfight" situation, this is the speed I'm trying to maintain in order to "out-turn" an adversary. It's also the speed above which I must excercise caution to prevent "Over-G" damage. Below this speed I must remain "Stall vigilant.

Is there a central location where the cornering speeds of CLoD aircraft can be found?

In the course of my interest in finding out accurate information so as to accurately measure Energy Maneuverability modeled into this Combat Flight Simulator I will be working the angles of attack that intend to reach the goal of answering that basic question above, and there are a few vital questions that are derived from that basic, or principle, question.

Such as:

1.
Are pilot g force limits equal for every on-line user of the game?

2.
What is the pilot g force limit for any on-line user of the game?

3.
Are any of the Fighter Planes modeled in the game with structural g force limits that are lower than pilot g force limits; therefore a pilot can break a plane before a pilot blacks out in this game?

Game = Combat Flight Simulator

I hope that my interest is well received here, and I further hope that all animosity can be set aside in a mutual interest in finding the facts, documenting the facts, and avoiding misunderstanding, confusion, misdirection, division, etc.

There are many reasons I can report here as to why these questions are vital as the Corner Velocity question exemplifies, since accurate information that accurately reports Corner Velocity is nearly the full measure of which plane is superior to the other plane in Aerial Combat.

I will try to recover my lent out copies of Fighter Combat by Robert Shaw, and Boyd by Robert Coram, and many other previously uncovered reports of vital information that can support the viewpoint that Energy Maneuverability is worthy of our mutual interest.

Corner Velocity is reported on the charts posted in the thread linked above, and I hope that I am not bending the rules too much by re-posting them now, since there are other comments that I think are vital as to these charts that report Relative Performance including Corner Velocity (instantaneous turn performance) and Sustained Turn Performance.





Questions concerning those numbers:

1.
Are those numbers accurate representations of averages for production planes?

2.
Are those numbers accurate for 2 specific actual airplanes?

3.
Are those numbers based upon actual flight tests?

4.
Are those numbers based upon calculations and if so who did those calculations, which formulas were used, and which data was used in those calculations?

5.
Are the 109 Stall Lines (accelerated and sustained) based upon open or closed leading edge slats?

6.
What exactly is meant by Full Throttle, does it include any additional settings having to do with maximizing manifold pressure or air/fuel mixture such as might be considered to be Combat Power?

7.
Is there any information about game performance that is available (so far) to be able to plot out that same type of Chart which is an Energy Maneuverability type Chart.

Examples of Energy Maneuverability data can be found here:

http://www.aviation.org.uk/docs/flig...-FTM108/c6.pdf

Scroll down to:

Turn Performance and Agility
Figure 3.63
Turn Performance Characteristics

I hope that this can be a good start to a mutually beneficial discussion concerning Energy Maneuverability as this type of data can be documented and understood from historical data to actual game data whereby the interest is knowing accurate relative performance characteristics.

To that end there are multiple methods by which game performance can be precisely (within obvious tolerance limits) documented, so as to leave out subjective opinion (as much as possible).

[Kurfürst]

Welcome back Josf. I have missed those charts.

[JG14_Josf]

Thanks for the welcome back, Kurfürst, and it is encouraging to see that you continue to offer a well communicated viewpoint, and I hope that we can avoid repeating any irreconcilable contradictions that may have been generated in the past.

To which I will now attempt to communicate more information concerning the Energy Maneuverability angle of view generally and the corner velocity measure specifically.

To help broaden the scope of the data pool beyond those 2 charts that concern the 109E and the Spitfire, please consider helping in identifying the specific information being reported by utilizing the Navair Information and an additional example of the same type of EM Chart.

I can't (yet) cut and paste the Navair information other than text (no chart):

TURN PERFORMANCE AND AGILITY
6.51
Frontside
Backside Envelope limit
Line of constant
Windup turn
Steady turn,
Loaded acceleration
Loaded deceleration
Area of positive
nz
Ps
Ps= 0
V
L Vs Vmrt
True Airspeed - kn
V
T
Turn Rate - rad/s
w
Coincident
Boundary
NOTE: Lines are "thickened"
for distinction
Figure 6.36
TURN PERFORMANCE

I can borrow another chart:



Source:

http://www.sci.fi/~fta/JohnBoyd.htm

All that above may be GREEK to anyone sharing this interest in Accurately Measuring Relative Air Combat Performance.

RECAP:

Cornering Speed: "The lowest air speed at which a fighter can obtain the structural or aerodynamic limiting G force."

In the "dogfight" situation, this is the speed I'm trying to maintain in order to "out-turn" an adversary. It's also the speed above which I must excercise caution to prevent "Over-G" damage. Below this speed I must remain "Stall vigilant.

Is there a central location where the cornering speeds of CLoD aircraft can be found?

Obviously, to me, there is at least one other person who understands the significance of Corner Speed.

Please know the difference between Sustained Turn Performance and Accelerated or Instantaneous Turn Performance so as not to confuse the two.

Consider how much confusion might occur if someone were to confuse Accelerated or Instantaneous (Corner Speed) with Sustained Turn Performance with an example illustration.

Fighter A is dropping from a higher speed and higher altitude into the circle produced by Fighter B as Fighter B is maintaining or sustaining a level flight turn at Maximum Performance for a Sustained Turn.

Fighter A drops in behind Fighter B from higher altitude and higher speed, and the question that is asked will offer the reader an opportunity to test your understanding of Energy Maneuverability or Air Combat in general, to see if you are confused or not confused about the differences between Sustained Turn Performance and Instantaneous Turn Performance.

This is vital stuff, and if you are confused you may not even be able to recognize how vital this stuff is in fact.

Question:

Which plane will be able to turn a smaller turn radius and a faster turn rate when Plane A is dropping down into the turn of Plane B where Plane A is at Corner Velocity when it begins to track Plane B and where Plane B is maintaining a Sustained Turn at Maximum Sustained Turn Performance?

The answer must include a g force tolerance number for each pilot and so an arbitrary number can be added to the question so 5 g can suffice as the constant that is demanded in order to answer the question.

Plane A (Can be a Spitfire against Spitfire, 109 against 109, Spitfire against 109, Mig against Mig, F86 against F86, Mig against F86, Spitfire vs Mig, 109 vs Mig, etc.)

Plane B (can be any plane on those charts too)

Plane A is at the 5 g (pilot limited) Corner Speed at the time it dives into a tracking shot onto Plane B.

Plane B is flying a luffberry circle at Maximum Sustained Level Turn Performance Flight Path (Level turn at full throttle just above the stall or at CLMax angle of attack).

Which plane (Plane A or Plane B) in any case will turn inside which other plane when the assumption is that both pilots cannot tolerate more than 5 g?

Solve the question for 5 g as the pilot g limit - please.

Note: EM Charts can be made for each plane in the game by following the methods described in the Naviar link.

[335th_GRAthos]

Hi Josf,


It has been very many years, welcome back.

A piece of advice: Do not even bother...

This flight sim, at the current state, is miles away off target in terms of a.)transparency and b.)historic performance of flight models.

On the positive side, the climate of this forum and the friendliness of the fellow members towards each other makes everybody want to hang around and enjoy reading!



Enjoy


~S~

[JG14_Josf]

Il-2 enthusiast & Moderator

Please, moderator, let me know if your displeasure is such that you prefer that I do not continue any further discussion on this topic or on this forum for that matter.

I prefer not to be involved in forums where the moderators contribute to Flame wars.

[JG14_Josf]

This flight sim, at the current state, is miles away off target in terms of a.)transparency and b.)historic performance of flight models.

335th_GRAthos,

The concept of documenting the actual game performance concerning those plots that go on those charts so as to then accurately know where the current state of the flight model is and then to accurately know what is changed in the flight model is specifically demanded as my intended interest with this topic on Energy Maneuverability.

I failed to make that clear within the context of the first initial volley.

I may not be employing English very well.

If it can be known as to...

I can borrow again:

Cornering Speed: "The lowest air speed at which a fighter can obtain the structural or aerodynamic limiting G force."

In the "dogfight" situation, this is the speed I'm trying to maintain in order to "out-turn" an adversary. It's also the speed above which I must excercise caution to prevent "Over-G" damage. Below this speed I must remain "Stall vigilant.

Is there a central location where the cornering speeds of CLoD aircraft can be found?

If that can be known now, then any changes can be known later.

I hope that I can address this:

This flight sim, at the current state, is miles away off target in terms of a.)transparency

I prefer to address that before addressing this:

and b.)historic performance of flight models.

The question asked, if you please, could be answered, and I'm not begging the question, I am merely asking you personally, please, and thanks for the welcome, please engage in the discussion on the topic by entertaining an answer to the question concerning Plane A (Sustained turn) and Plane B (Diving in at Corner Speed), and which plane turns a smaller radius at a faster rate, and there can be three levels of answers relevant to the game and to this topic.

Assuming a 5 g pilot limit.

1.
The answer is provided by the 109 and Spitfire EM Charts, which are not superimposed one on top of the other. (WWII vintage?)

2.
The answer is provided by the Mig and F86 Chart, which has one plane superimposed on the other plane. (possible flight test data plotted onto that chart by John Boyd and Chuck Yeager concerning a captured Mig).

3.
The answer is provided by game flight tests. (I don't even know yet if the game offers usable information recorded in replay files).

Again addressing this:

This flight sim, at the current state, is miles away off target in terms of a.)transparency and b.)

Having in-game data, if it is accurate (repeatable from one computer to the next and from one test pilot to the next and from one test flight to the next or by average of many test flights), there can be a mathematical determination of which planes, which pilots, are blacking out at which g loads.

Note: In IL2 it became obvious that some planes were modeled to generate higher g loads and therefore that program was thereby able to vary Instantaneous turn performance for those planes so modeled relative to the planes that were not modeled with pilots that were not capable of sustaining as much g force.

Someone might ask me, or ask themselves, how can it be possible for someone to know if the game models the same g load for each plane?

That is the same point, the same question, as this Topic intends to answer.

If someone were to have two computer side by side and one pilot is turning the same diving turn as the other pilot, both pilots are following the highest performance downward spiraling turn, and one pilot is no where near black out while the other pilot is obviously being limited by black out, and both planes are nose to tail in the diving turn, what do you think that proves?

If you care to engage in the discussion: please consider answering the question.

I know for a fact that the IL2 game became widely variable in which planes were modeled with higher or lower g loads, depending upon which "mod" was being modded by whoever figured out how to alter that variable.

I know for a fact that I had asked many times on those IL2 forums if the game modeled the same g load for each pilot and as far as my memory goes I think the official answer was that the pilot g load was 5 g for every pilot flying every plane. That was later proven to be untrue, but the cause of the variations are probably attributable to modifications done to the original program.

How important is it to have a 1 g advantage in modeling for your pilot when you fly your plane against an opponent where the opponent is flying with 1 g less tolerance in g load; where your opponent is fighting against black out, right in front of you, and you ask him on Teamspeak, and the opponent confirms on Teamspeak, "I am fighting black out", and you in your plane can merely pull back on the stick, no black out, pull lead, start shooting, score hits, and so, again, how important is it to know if your plane, and your pilot can tolerate the same g force, more g force, or less g force, and how important is that information compared to which plane can go 5 km/h faster on the deck, or which plane can maintain 1 g more in a luffberry circle or sustained turn at a constant altitude?

I'm asking, and I think I am asking nicely, and already the moderator is starting a flame war?

What is up with that?

[JG14_Josf]

Rather than entertain the topic, and rather than entertain the question, the responses so far are somewhat off topic, so an effort to return to focus appears to be possible if not wanted - yet.

There may be someone, somewhere, sharing an interest in Corner Speed and Energy Maneuverability as it relates to the relatively new game CloD.

Case in point:

Cornering Speed: "The lowest air speed at which a fighter can obtain the structural or aerodynamic limiting G force."

In the "dogfight" situation, this is the speed I'm trying to maintain in order to "out-turn" an adversary. It's also the speed above which I must excercise caution to prevent "Over-G" damage. Below this speed I must remain "Stall vigilant.

Is there a central location where the cornering speeds of CLoD aircraft can be found?

I have been warned:

A piece of advice: Do not even bother...

Thanks for the advice.

My hope, which has already been expressed in English, is to discuss the topic with people who share an interest in the topic.

This is not a far fetched hope, since I found someone else who may have expressed a similar interest, which has already be quoted several times.

Perhaps he gave up without a fight?

Hit and run?

How about a description of one of the many methods that can be used to accurately determine the vital measure of Corner Speed and again I can access the already linked Navair site.

How about The Wind up Turn?

6.4.1 WINDUP TURN
Instantaneous turn performance is documented usually with the windup turn
technique. In this technique the load factor is smoothly and steadily increased with constant Mach number. The end point of the data run is the accelerated stall or the structural limit, whichever is reached first.
To perform the windup turn, momentarily stabilize at the desired Mach number. Set the thrust for the test as you roll into a turn and smoothly increase load factor. As load factor and drag increase, reduce the pitch attitude in order to keep Mach number constant.
Use bank angle to adjust the pitch attitude. When the limit condition is reached, record the g level. Increase the load factor no faster than 1/2 g/s to minimize the effects of unsteady flow.

There is more information offered on that site to explain the need to avoid "the effects of unsteady flow", and that may be well (or poorly) modeled in the game globally or it may be relatively well (or poorly) modeled from one plane to the next.

Knowing Corner Velocity may be of no interest to anyone else, I can't know without asking.

[335th_GRAthos]

Josf, you are right with your point, transparency has to addressed first.

1C publicly stated that they are not prepared to provide us with the performance plots of the current flight models in a way similar to what we had available in IL2FB (see below).





Probably (quote 1C) we will have them with the sequel (I became very modest with my demands after one year CoD experience).

So, until I have a possibility to understand the CoD flight models, it is of limited benefit to indulge into a discussion on the theory of dogfight.

Actualy, why don't you have a try yourself? Try to fly some planes in CoD (offline and online) and tell us how their performance feels like.

~S~

[JG14_Josf]

So, until I have a possibility to understand the CoD flight models, it is of limited benefit to indulge into a discussion on the theory of dogfight.

Actualy, why don't you have a try yourself? Try to fly some planes in CoD (offline and online) and tell us how their performance feels like.

335th_GRAthos,

You sound as if you are as interested in Relative Performance as I am; however this type of Forum with this type of responses (off-topic to say the least) has me on guard, so I am going to trust that your intent is to share an interest and I am not going to jump to the conclusion that you are setting me up for something nefarious (some kind of flanking maneuver).

I will take this opportunity to work at understanding the differences between our viewpoints in this way:

Those IL2 charts offered on this Topic are not on this Topic since those charts have to do with Sustained Turn Performance (maintaining a fixed energy state) and therefore they do not have to do with Maneuvering in Combat (except for a luffberry circle type of defense or attack) and I already offered a question to be answered along those lines.

One exception to that above observation, and report, is the climbing data, which is a measure of Excess Power, which can then be extrapolated (roughly) to find the Accelerated Stall line, and the Maneuvering Envelope (as can level acceleration tests) if I understand things well enough.

I do not claim to understand things well enough, hence the desire on my part to engage in discussion with people sharing a similar interest.

Climb performance and level acceleration performance is at least as good as, and probably much better than, Sustained Turn Performance, when the idea is to compare one fighter to another to see which can outperform the other in very specific and unambiguous ways - not limited to the Luffberry Circle maneuver also known as the Sustained Turn.

In Naviar terminology the following English words apply:

Ps= 0

I can't show that Navair charts but the WWII era charts (If I am reading them right) and the Korea era chart (Boyd's) shows that Sustained (Ps=0) Turn Performance Curve.

Now, please, onto your very welcome words - in English:

So, until I have a possibility to understand the CoD flight models, it is of limited benefit to indulge into a discussion on the theory of dogfight.

Corner Velocity, to be more specific, is not a Theory. Corner Velocity in real life is a very precise air speed and g load which will then correspond to an exacting turn rate and turn radius. Each real plane and each simulated plane has a corner velocity.

Please consider the possibility that this is not mere theory.

Actualy, why don't you have a try yourself? Try to fly some planes in CoD (offline and online) and tell us how their performance feels like.

I just loaded up the game after having a few weeks of problems failing to get the Patch to work on my old Windows XP system. I now have an upgraded system purchased specifically this game and I will be learning the Corner Speed of the 109 relative ot the Corner Speed of the opposition, that is a consequence of playing the game, as to documenting the actual Velocity, Turn Rate, Turn Radius, or G load: that may yet happen, if there is any interest in it. If there is no other interest in it other than my own, then I don't need to write down any numbers, I'll know which plane has the better corner velocity and I'll have a reasonable understanding of how much better the better plane can maximize turn performance.

I can borrow, again, from the Navair site and again, please, consider that this is not theory or "feel", since the time it takes to complete 360 degrees of turn is exactly that much, not more, and not less, and if one of the other variables can be known, then all four variables can be known with enough precision to get well past subjective opinion.

Naviar on Corner Velocity:

6.3.4.6 CORNER SPEED
The significance of the corner speed can be seen in figure 6.15. At the speed
corresponding to the intersection of the lift boundary and the structural limit, the minimum instantaneous turn radius and maximum instantaneous turn rate are achieved. Thus, VA is the speed for maximum turn performance when energy loss is not a consideration.

That is not theory, and if any two of the four variables are known then the other four can be calculated.

1.
Turn Rate
2.
Turn Radius
3.
Airspeed
4.
G load

To clarify the relevance to the intended focus of this discussion the g load factor is crucial since the g load factor may, or may not, be constant for every plane and therefore some planes (not advertized as such) may be favored over other planes as the CODE (not theory, and not "feel") may CODE a higher g load for one plane compared to another plane.

Not knowing that fact may cause someone to focus attention on Sustained Turn Performance as being better in one plane and not as good in another plane when in fact the maximum pilot g load variable may be 1 g higher in the plane with the poor sustained turn rate.

A plane with a low sustained turn rate and a better (lower) corner velocity is exemplified in the Mig versus F-86 Maneuvering Diagram supplied by Boyd.

If you have read Robert Shaw's Fighter Combat then you may remember something called Double Inferior and Double Superior and this (not theory) is the method by which a plane can be Single Inferior to another plane, such that, for example, the Mig can Sustain a higher level g load, due to higher power loading and lower wing loading while the F-86 has the lower Corner Velocity.

Why?

Now there may be much in the way of room for theory, but the data is what the data is, not subjective, and not subject to feel, and not subject to opinion.

Liars and cheats can divert from the actual data, shooting the messenger, causing flame wars, whatever, but the data is what it is until someone can improve on the accuracy of the data and then there is less error in the data.

Who wants error in the data?

Not me.

Back to your very welcome words:

Josf, you are right with your point, transparency has to addressed first.

1C publicly stated that they are not prepared to provide us with the performance plots of the current flight models in a way similar to what we had available in IL2FB (see below).

What is so difficult about admitting that the game does, or does not, model the same g load for each pilot flying each plane?

Who cares, really, if the players can extrapolate the facts and answer the question ourselves, and then if the game suddenly changes, we know better because we already have the data that proves how the game was, and we have the data that proves how the "patch" changed the game?

I'm asking, I'm not dictating, and I hope that you can tell the difference. It is not a subtle difference.

As to "feel":

I have (in my youth) accumulated 40 hours logged airtime flying Hang Gliders. I know the feel of a wing cutting through the fluid that is known as air. This Clod simulator, to me, feels very good, there are better sounds (or my new system has a better sound card), and the general stickiness, then "buffet", then the break of acceleration on the lift vector is very encouraging, much fun, I can fly around for hours doing nothing more than feeling out the fight model - so far. That is not on-topic.

[TUSA/TX-Gunslinger]

Originally Posted by Kurfürst

Welcome back Josf. I have missed those charts.

+1

I'll take Josef's apprearance as a sign of good luck!