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Why the Albatros and Pfalz speeds can never be fixed.


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#1 Spoon

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Posted 20 July 2012 - 05:25

The following is meant as a discussion piece and doesn't actually prove anything. It is merely my opinion based on the best of my knowledge at the present moment. While feedback is much appreciated (good or bad), please read this in the spirit its intended.




Why the Albatros and Pfalz speeds can never be fixed.

In older flight sims, all aspects of an aircrafts performance were set independently. The developer set the maximum speed, rate of climb, roll rates, times to turn and many other variables to match historical data. If a plane was too slow, it was easy to adjust its maximum speed without affecting other performance indicators. This meant that developers could create aircraft that exactly match the performance from known flight test but left the aircraft feeling 'wooden'. These aircraft weren't being controlled by mathematical models but by spreadsheets.

With ROF, things are very different. In ROF, the developers create an exact aerodynamical model of the aircraft and give it its historical power output. The speed or rate of turn of an aircraft at any point in the sim isn't taken from a spreadsheet like older flight sims but dynamically calculated by applying state of the art mathematical models to the aerodynamical model/power output for the given aircraft under the atmospheric conditions present in the game. The performance of a Camel or Fokker D.VII in ROF isn't based on some dodgy flight test but calculated by advanced mathematics. That these figures come out so close to what is expected is an example of how good today’s aerodynamical modelling is.

But of course there are some problems with this hologistical approach. When the mathematical models produce performance which doesn't match historical records, little can be done to change it. Little tweaks can be made to the aerodynamical model of an aircraft without affecting historical accuracy but increasing one variable almost invariably causes a decrease in another. Tweaking the CL of a wing to produce more lift (and a tighter turn) also produces more drag and reduces the maximum speed. Tweaking the pitch of the propeller to increase maximum speed will decrease acceleration and rate of climb. The 777 developers do an amazing job tweaking the aerodynamic models to match what we know of these aircraft but they can only do so much.

One area we see a large divergence between the expected and the actual in ROF is in the unexpectedly low maximum speeds of thin high camber wing German aircraft (Albatros Ds and Pfalz D.IIIa). Official flight trials conducted at the First Fighter Completion at Adlershof between 21 Jan and 12 Feb 1918, gave the Albatros D.Va 180ps D.IIIau a level speed of 186km/h (116mph) and the Pfalz D.IIIa 180ps D.IIIau a level speed of 185km/h (115mph). While our versions are fitted with the Mercedes D.IIIa engine, they still should do a lot better than the 103mph of the present Albatros D.Va.

So what is wrong? The thin high camber wing is an aeronautical anomaly found briefly for a couple of years during the middle of WW1. Theoretically these planforms offered very high lift for low drag but even at the time, there was suspicion their performance would not match theoretical results.

NACA Report 279, Page 455 - Discussing the Albatros wing planform
“It therefore follows that very high lifts on highly cambered sections found in tests at moderate Reynolds Numbers should be viewed with suspicion since it is unlikely that they can be realized at full scale.”

We now know these extinct wing planforms weren't the miracles they were thought to be. We know they weren't high-lift low-drag, but did they actually produce the high CL's predicted and with it high drag, or did they perform more like other thin wings and produce lower CL numbers but lower drag. As these planforms are dinosaurs on the edge of mathematical understanding, we're still not sure.

In ROF, the current mathematical models assume they do produce high-lift and high-drag and as a result we have a Pfalz D.IIIa which will out turn a Fokker D.VII but can't come close to its historical maximum speed. The less cambered wing of the Albatros, while not producing the level of distortion of the Pfalz D.IIIa still produces too much lift and too much drag and hence can't reach historical speeds.

Unfortunately, this really leaves 777 with no way to fix the problem. Other than make unhistorical changes to the thin high camber planforms which would open a can of worms and most certainly not be in the best interest of the game, there is little that can be done. Unless our knowledge of how these wings performed suddenly increases and with it the mathematical models to simulate it, we're stuck with slow Albatros and Pfalz

Spoon 8-)
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#2 Scott_Steiner

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Posted 20 July 2012 - 06:24

Somewhat of a sensationalized title and post.. I believe you are trying to use these statements to jump-start a discussion with thorough analysis on these planes physics in hopes of them getting changed (even though you state they can not) but don't let me put words in your mouth :)

That is the beauty and problem with a real living breathing physics engine isn't it? Everything is one big jigsaw puzzle, every piece effects another.

I do think though, that you are over-elaborating what the ROF physics engine actually does (not that I know what is or isn't modelled I may be completely ignorant).You make it sound like ROF looks at the wing profile or runs air over the 3d model of a the wing, figuring out its shape. I would think it would just be a drag co and a lift co.. Maybe you are saying the game skews the physics off if these characteristics are out of a certain ballpark typical of the day that a higher-profile wing would give?

I fail to see how there is no possibility of getting these aircraft into a closer ballpark when you can edit lift and drag independently, regaurdless of what NACA says this type of wing should do, you can modify one atrribute or the other, or add horsepower or decrease horsepower (we call this fudging).

If airplane speed and climb rate can get closer to historical data but the turning rate is too greatly improved, I say why not decrease max elevator deflection available to the pilot (in the physics engine not visually on the 3D model), this is all smoke and mirrors after all.
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#3 elephant

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Posted 20 July 2012 - 06:51

Interesting!
RoF doomed by it's own sophistication!
Let see what the "officials" will have to say on that…
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#4 LukeFF

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Posted 20 July 2012 - 11:44

TL;DR
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#5 gavagai

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Posted 20 July 2012 - 12:16

One area we see a large divergence between the expected and the actual in ROF is in the unexpectedly low maximum speeds of thin high camber wing German aircraft (Albatros Ds and Pfalz D.IIIa). Official flight trials conducted at the First Fighter Completion at Adlershof between 21 Jan and 12 Feb 1918, gave the Albatros D.Va 180ps D.IIIau a level speed of 186km/h (116mph) and the Pfalz D.IIIa 180ps D.IIIau a level speed of 185km/h (115mph). While our versions are fitted with the Mercedes D.IIIa engine, they still should do a lot better than the 103mph of the present Albatros D.Va.

Do you have a link or something that lists out those details? This diagram shows the D.Va attaining that same airspeed with only the D.IIIa engine.

Attached File  AlbatrosDV.jpg   570.48KB   2126 downloads

Anyway, if I understand your hypothesis correctly, that the FMs cannot be changed, I don't believe it is true. There's a lot of plasticity in the Rise of Flight flight models. Just look at what Petrovich did for the Nieuport 17.

——————

NACA Report 279, Page 455 - Discussing the Albatros wing planform
“It therefore follows that very high lifts on highly cambered sections found in tests at moderate Reynolds Numbers should be viewed with suspicion since it is unlikely that they can be realized at full scale.”

We now know these extinct wing planforms weren't the miracles they were thought to be. We know they weren't high-lift low-drag, but did they actually produce the high CL's predicted and with it high drag, or did they perform more like other thin wings and produce lower CL numbers but lower drag

That is very interesting and could go a long way in explaining the crazy-good low speed handling of some of our German scouts.

——————

One other comment:
Do we know that aircraft performance data from WW1 is sufficiently accurate and precise to be writ-in-stone for something like a computer flight sim game? Most seem to assume that it is, but I have never seen justification for it.
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#6 Damocles

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Posted 20 July 2012 - 19:07

I could handle an Alb or DIII that lost some lift in relation to an increase in spread.

Gavagai wrote:
"That is very interesting and could go a long way in explaining the crazy-good low speed handling of some of our German scouts"

Are you possibly suggesting that RoF see's the thin high cambered wing as a "thick" wing and giving it the same benefits ?
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#7 Spoon

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Posted 21 July 2012 - 07:40

Hi Gents,

@Scott Steiner.

No, I really do believe that the Albatros and Pfalz can’t be fix.

How an aircraft performs in this sim is dependent on 3 major things.
1. The aerodymanical model of an aircraft (made up of lots of little bits joined together)
2. The engine output which is applied to the thrust line of the aerodymanical model
3. The Mathematical algorithms which then calculate how the model should react and perform at any moment in time.

I’m almost positive you’ll find that the aerodynamical models of the Albatros and Pfalz have been painstaking rendered by 777 to near perfection and that the engine output is correct too. The problem here is that the state of the art mathematical algorithms don’t work very well with a First World War wing planform that is still not properly understood today.

777 doesn’t have the time or money to lead the entire world’s scientific community and develop better mathematical modelling so the only way 777 could fix the problem would be to make non-historical changes to the aerodymanical model to match their hunches on the perceived errors in the state of the art mathematical algorithms. Yes… it is as stupid as it sounds and hence will never be done.

@LukeFF. I value your opinion as much as you valued reading mine :)

@gavagai

Those performance details came from the late (and great) Dan san Abbott. Where he got them from I don’t know but as he was a respected author of WWI aviation history, I’d bet my life they’re right.

The changes made to the N17 and SE5a made them feel a lot more realistic but nothing fundamental changed. The N17 for instance is still too slow. The aerodymanical model is a bit like Einstein’s E=mc2. Nothing can be created from nothing so if you want to increase something, something somewhere will be lost. The only way to add more energy to a aircraft is to add more power, a step 777 have done with the Pfalz D.XII and Haberstadt. Adding the Mercedes DIIIau will not produce a historically fast Albatros or Pfalz

@ Damocles

Is the mathematical model interpreting the thin high camber wings as Иfat’ wings? Yep, I think that’s pretty much exactly what it’s doing. When Fokker created the Fat winged D.VII he reduced its wing area to less any of its historical contemporaries. Why? Because if he didn’t reduce its wing area the high-lift high-drag fat wing of the D.VII would have made in much more manoeuvrable than its contemporaries but much slower. Fokker sacrificed some of this lift for more speed and a better roll rate. The in game Albatros and Pfalz are both trying to push aprox 22m2 of Иfat’ wing through the air. They turn on a dime but the speed… sheesh!

Spoon
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#8 LukeFF

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Posted 21 July 2012 - 08:48

I value your opinion as much as you valued reading mine :)

Sure, but the thing is that we've gone around and around and around and around and around on FMs since this game was released. The devs have the relevant data needed for each plane, and it's up to them what to do with it.

It's nothing against you, trust me. :) But, it just gets tiresome with these FM debates constantly being rehashed.
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#9 hoots2

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Posted 21 July 2012 - 09:27

Hey Luke, you know you don't have to read them yes? This seems to me to be a reasoned and polite discussion. People are interested in the workings and mechanics of the game, this is a good thing. Spoon isn't saying anything detrimental at all. Just let this one run and if you don't like it don't read it.
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#10 =AH=_Sid

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Posted 21 July 2012 - 09:39

I value your opinion as much as you valued reading mine :)

Sure, but the thing is that we've gone around and around and around and around and around on FMs since this game was released. The devs have the relevant data needed for each plane, and it's up to them what to do with it.

It's nothing against you, trust me. :) But, it just gets tiresome with these FM debates constantly being rehashed.

LOL, you better get used to it Luke Image

In the twelve plus years I've been flying combat flightsims, the sim in question may have changed, the development team, the company, the computer I'm playing on, the equipment I'm using with it, the aircraft I'm flying, the era I'm flying, the names of my adversaries, but there's been one unchanging constant in all that time - the hotly debated/argued FM discussions! (I think AirWarrior invented it Image )
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#11 Chill31

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Posted 21 July 2012 - 13:18

Unfortunately, this really leaves 777 with no way to fix the problem. Other than make unhistorical changes to the thin high camber planforms which would open a can of worms and most certainly not be in the best interest of the game, there is little that can be done. Unless our knowledge of how these wings performed suddenly increases and with it the mathematical models to simulate it, we're stuck with slow Albatros and Pfalz

Spoon 8-)

I disagree as well. What is unhistorical, using "good" data and getting incorrect results or using "bad" data and getting correct reults? There is a lot of room for getting these FMs right.
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#12 Eckhart

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Posted 21 July 2012 - 14:11

The following is meant as a discussion piece and doesn't actually prove anything. It is merely my opinion based on the best of my knowledge at the present moment. While feedback is much appreciated (good or bad), please read this in the spirit its intended.




Why the Albatros and Pfalz speeds can never be fixed.

In older flight sims, all aspects of an aircrafts performance were set independently. The developer set the maximum speed, rate of climb, roll rates, times to turn and many other variables to match historical data. If a plane was too slow, it was easy to adjust its maximum speed without affecting other performance indicators. This meant that developers could create aircraft that exactly match the performance from known flight test but left the aircraft feeling 'wooden'. These aircraft weren't being controlled by mathematical models but by spreadsheets.

With ROF, things are very different. In ROF, the developers create an exact aerodynamical model of the aircraft and give it its historical power output. The speed or rate of turn of an aircraft at any point in the sim isn't taken from a spreadsheet like older flight sims but dynamically calculated by applying state of the art mathematical models to the aerodynamical model/power output for the given aircraft under the atmospheric conditions present in the game. The performance of a Camel or Fokker D.VII in ROF isn't based on some dodgy flight test but calculated by advanced mathematics. That these figures come out so close to what is expected is an example of how good today’s aerodynamical modelling is.

But of course there are some problems with this hologistical approach. When the mathematical models produce performance which doesn't match historical records, little can be done to change it. Little tweaks can be made to the aerodynamical model of an aircraft without affecting historical accuracy but increasing one variable almost invariably causes a decrease in another. Tweaking the CL of a wing to produce more lift (and a tighter turn) also produces more drag and reduces the maximum speed. Tweaking the pitch of the propeller to increase maximum speed will decrease acceleration and rate of climb. The 777 developers do an amazing job tweaking the aerodynamic models to match what we know of these aircraft but they can only do so much.

One area we see a large divergence between the expected and the actual in ROF is in the unexpectedly low maximum speeds of thin high camber wing German aircraft (Albatros Ds and Pfalz D.IIIa). Official flight trials conducted at the First Fighter Completion at Adlershof between 21 Jan and 12 Feb 1918, gave the Albatros D.Va 180ps D.IIIau a level speed of 186km/h (116mph) and the Pfalz D.IIIa 180ps D.IIIau a level speed of 185km/h (115mph). While our versions are fitted with the Mercedes D.IIIa engine, they still should do a lot better than the 103mph of the present Albatros D.Va.

So what is wrong? The thin high camber wing is an aeronautical anomaly found briefly for a couple of years during the middle of WW1. Theoretically these planforms offered very high lift for low drag but even at the time, there was suspicion their performance would not match theoretical results.

NACA Report 279, Page 455 - Discussing the Albatros wing planform
“It therefore follows that very high lifts on highly cambered sections found in tests at moderate Reynolds Numbers should be viewed with suspicion since it is unlikely that they can be realized at full scale.”

We now know these extinct wing planforms weren't the miracles they were thought to be. We know they weren't high-lift low-drag, but did they actually produce the high CL's predicted and with it high drag, or did they perform more like other thin wings and produce lower CL numbers but lower drag. As these planforms are dinosaurs on the edge of mathematical understanding, we're still not sure.

In ROF, the current mathematical models assume they do produce high-lift and high-drag and as a result we have a Pfalz D.IIIa which will out turn a Fokker D.VII but can't come close to its historical maximum speed. The less cambered wing of the Albatros, while not producing the level of distortion of the Pfalz D.IIIa still produces too much lift and too much drag and hence can't reach historical speeds.

Unfortunately, this really leaves 777 with no way to fix the problem. Other than make unhistorical changes to the thin high camber planforms which would open a can of worms and most certainly not be in the best interest of the game, there is little that can be done. Unless our knowledge of how these wings performed suddenly increases and with it the mathematical models to simulate it, we're stuck with slow Albatros and Pfalz

Spoon 8-)

Just wanted to say thank you for explaining this to us non-specialists! Very convincing indeed! This should reduce any unnecessary bickering about "why is the Pfalz so slow?"…and increase the respect for the great work the ROF team has accomplished.
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#13 Miggins

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Posted 21 July 2012 - 15:40

If airplane speed and climb rate can get closer to historical data but the turning rate is too greatly improved, I say why not decrease max elevator deflection available to the pilot (in the physics engine not visually on the 3D model), this is all smoke and mirrors after all.

This is an interesting bit.

In some past FM debates some people seem to be equating the mathematical flight model and the visible 3D model, but it is my understanding the the visual model is grafted onto the maths FM and that's all, so an adjustment to the math model need not be shown on the 3D model, so you could get changes in the planes mentioned in the OP without us end-users seeing a different depiction of the planes on our screens.

It all depends on where you are coming from and what you want to achieve.

Currently some planes don't abide by some historical performance data, but providing we are aware of these divergences we can accomodate them into our gameplay.
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#14 Tom-Cundall

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Posted 21 July 2012 - 15:46

Those performance details came from the late (and great) Dan san Abbott. Where he got them from I don’t know but as he was a respected author of WWI aviation history, I’d bet my life they’re right.

He was a great contributed, collector and writer but he had some pretty leftfield theories as well (convinced the Hawker Richthofen fight was 35 minutes long for example)

He was also known (as all good historians are) to revise his stance in light of new thinking or evidence see his thinking that all Mercedes engines with an upright air pump were D.IIIaü for example - later retracted.

[For another good example of an author u-turning in light of further research see Leon Bennet's latest work!]

DSA wouldn't have staked his life on those figures and neither should you if DSA is the only source. DSA is not a primary source - without knowing where the figures originally came from they only useful as an interesting aside. What source does he quote?
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#15 zachanscom

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Posted 21 July 2012 - 17:41

i think you guys confuse refusal for inability.
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#16 gavagai

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Posted 21 July 2012 - 21:40

The Albatros D.Va and Pfalz D.IIIa make up the bulk of the CP fighter force from Summer 1917 to Summer 1918. With those two aircraft underperforming so badly that they are meat-on-the-table against competent opposition, we end up with an entire year of WW1 that is unsuitable for human versus human play. Throwing everyone into a Dr1 that is just as over-inflated as some of the British planes is not an acceptable solution.

For the sake of my sanity (and maybe the sanity of others) I still have to hope that somehow, some way, something might be done to ameliorate the situation.
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#17 zachanscom

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Posted 21 July 2012 - 22:15

actually, lots of the flight model discussions take place on english board, and most of the devs seem to be russian. maybe we just need a liaison to relay the message to them.
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#18 Damocles

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Posted 22 July 2012 - 01:41

actually, lots of the flight model discussions take place on english board, and most of the devs seem to be russian. maybe we just need a liaison to relay the message to them.


What do the Russians mostly talk about then ?
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#19 gavagai

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Posted 22 July 2012 - 03:34

Moscow has known about our Albatros D.Va complaint since 2009: Albatros D.Va performance
They are perfectly aware of what we talk about here.
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#20 Mogster

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Posted 08 August 2012 - 17:51

Well the dispersion change took a lot of persuasion.

There's been a list of constant complaints about ROF, stuff that gets repeated over and over. Gradually the list is getting shorter as things get fixed or changed. If I was the developer I'd want the Camel and Albatros flight model issue resolved as it ticks something else off the list of common complaints. It'd be good PR.
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#21 NewGuy_

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Posted 08 August 2012 - 18:37

I wish that the ROF FM was such that you could drop and add new engines, then FM issues would not be such a biggie. You could just sell engine add-ons, then everyone could get the widest number of variations, for each machine possible. I for one would like to drop a 220 HP V8 Hispano-Suiza 8Be, or a 235 hp HS 8BEc, into my current 200 hp V8 Hispano-Suiza 8Ba SPAD XIII. Maybe, if there is an ROF 2, the team will use a game engine that will allow for this type of drop and swap system. Then you could have a Pfalz DIII with the DIIIau engine, a DRI, with a captured Gnome engine, etc.. :S!: MJ
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Something something SPAD. Something something then dive away. 


#22 BADMUTHA

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Posted 08 August 2012 - 20:18

I just wish the albatros could catch any entente plane, Albatrosses seem so blazing fast in videos but they move like sloths in ROF.
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#23 Scott_Steiner

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Posted 08 August 2012 - 23:32

I wish that the ROF FM was such that you could drop and add new engines, then FM issues would not be such a biggie. You could just sell engine add-ons, then everyone could get the widest number of variations, for each machine possible.

Unfortunately that is not how most (the better) physics engines in games work.

Also, I think you should become a professional lobbyist based on how many ways you try to fit the 220hp Spad into every thread.
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#24 =Fifi=

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Posted 09 August 2012 - 00:47

So, to make it short, no computer mathematical way can model the real Alb and Pfalz performances?
Or just the ROF engine?
It's a bit chineese for me…
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#25 JimmyBlonde

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Posted 09 August 2012 - 01:01

1+1=2 except for varying values of '1' is what it boils down too.

The $64,000 question is: "Which '1' is diverging from the nominal value?"
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#26 Gadfly21

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Posted 09 August 2012 - 01:14

I just wish the albatros could catch any entente plane, Albatrosses seem so blazing fast in videos but they move like sloths in ROF.

Well, they shouldn't be able to catch just any entente plane, but they should be faster than Camels, for instance.

The D.Va should have a top speed of 186 kph, according to my sources*, but it's only about 170 kph in the game. The SE.5 and Spad VII with the earlier versions of the Hispano-Suiza engine could only go about 185-195 kph as well, and would make a nice match for the Albatross.

The SE.5a is much faster, but the flight model seems quite accurate, with a top speed of 222kph. It totally outclasses the current Albatross, and will continue to do so, even if the Alb is fixed (which it should).

The Sopwith Camel on the other hand has a listed top speed of about 185kph, according to sources. However, according to the store page, the ROF Camel goes a little over 190kph. It's not a big difference, but it's significant when the slowness of the Albatross is considered.

Another tidbit is that the Pfalz D.IIIa can reach 180 kph TAS at 5000m, according to the store page. I've read, but can't remember the source, that the top speed was 185kph at this altitude.

*"Biplanes, Triplanes, and Seaplanes" by Michael Sharp, and Wiki.
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#27 NewGuy_

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Posted 09 August 2012 - 02:15

I wish that the ROF FM was such that you could drop and add new engines, then FM issues would not be such a biggie. You could just sell engine add-ons, then everyone could get the widest number of variations, for each machine possible.

Unfortunately that is not how most (the better) physics engines in games work.

Also, I think you should become a professional lobbyist based on how many ways you try to fit the 220hp Spad into every thread.

I would love to work for SPADPAC. :lol: :S!: MJ


Lobbying is a great career field. I remember a woman calling one of her relatives, "One of the bad guys," for working as an oil lobbyist…My advice to her was, "Good guy, bad guy, he is a damn good connection. Stay in touch with that guy!" :lol:
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Something something SPAD. Something something then dive away. 


#28 BADMUTHA

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Posted 09 August 2012 - 10:20

I just wish the albatros could catch any entente plane, Albatrosses seem so blazing fast in videos but they move like sloths in ROF.

Well, they shouldn't be able to catch just any entente plane, but they should be faster than Camels, for instance.

The D.Va should have a top speed of 186 kph, according to my sources*, but it's only about 170 kph in the game. The SE.5 and Spad VII with the earlier versions of the Hispano-Suiza engine could only go about 185-195 kph as well, and would make a nice match for the Albatross.

The SE.5a is much faster, but the flight model seems quite accurate, with a top speed of 222kph. It totally outclasses the current Albatross, and will continue to do so, even if the Alb is fixed (which it should).

The Sopwith Camel on the other hand has a listed top speed of about 185kph, according to sources. However, according to the store page, the ROF Camel goes a little over 190kph. It's not a big difference, but it's significant when the slowness of the Albatross is considered.

Another tidbit is that the Pfalz D.IIIa can reach 180 kph TAS at 5000m, according to the store page. I've read, but can't remember the source, that the top speed was 185kph at this altitude.

*"Biplanes, Triplanes, and Seaplanes" by Michael Sharp, and Wiki.

I have a difficult time catching a straight and level SE5a by diving from a 2000 ft+ advantage, same with N17's it seems to a lesser extent.
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#29 Mogster

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Posted 09 August 2012 - 10:37

As I see it the Albatros party was well and truly over by mid 1917. That doesn't mean they shouldn't be faster though, having them run down by the Camel and DR1 with a 10mph speed advantage is a a "feature" that should have been thrown out by a sanity check at the alpha stage.

What we don't know, well OK I don't, is how the dev's feel about the data they have. I just can't go for this impossible physics arguement, difficult maybe but impossible… As I said earlier I get the feeling that the dispersion increase wasn't something they 100% agreed with but it seems to have been received well by the community. I get the feeling there's a similar situation with some of the flight model issues, "look we've modelled it to the data, here it is"
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#30 gavagai

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Posted 09 August 2012 - 14:06

As I see it the Albatros party was well and truly over by mid 1917. That doesn't mean they shouldn't be faster though, having them run down by the Camel and DR1 with a 10mph speed advantage is a a "feature" that should have been thrown out by a sanity check at the alpha stage.

It's hard to see how a plane that dominated in the Spring could be over in the Summer. Some lazy historians and laymen have put far too much on a single quote, MvR's quip about the 'lousy' Albatros. Other pilots were more specific in their criticism, e.g. Von Tutschek's complaint that the SE5a, 180hp Spad VII, and F.2b could all outclimb the Albatros and engage or disengage at will that way. On the other hand, he opines in the same paragraph that the Albatros was faster than 'the Sopwith' and 'Nieuport' and could 'nearly match them in climb' (my paraphrase).

Like a lot of other German aces, he put up an impressive string of kills in the Albatros, and eventually bought it in the ace-killer, the Fokker Dr.1.
http://www.theaerodr...ny/tutschek.php" onclick="window.open(this.href);return false;">http://www.theaerodr...ny/tutschek.php

As for the sanity check, Loft himself told us in the simHQ interview that he started out knowing very little about WW1 aviation. I don't know if the same is true of other members of the team, but it offers some explanation of how the backward airspeeds could be missed. If you have data in front of you that seems unambiguous, and you don't know of any reason to doubt it, you go with it.

All that said, there is still a lot of work to be done. The Camel's RPM does not match the Tripe's (1400 vs 1200 rpm, respectively), the Pup and F.2b both have pumped up climb times, the Dr1 flies like it's a Le Rhone engined Voss special, and the Fokker D.VII is a turd.
:x
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#31 Mogster

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Posted 09 August 2012 - 18:56

Things seem to have changed very quickly in WW1, planes that dominated became deathtraps in a few months. A good pilot was still a good pilot in almost any equipment though, in his diary McCudden, with surprising honesty, talks about being given the run around in his SE5a by a DFW….

Both Yeates and Cecil Lewis both mention how unthreatening the Albatros DVa was to the Camel and SE5a drivers. Yeates talks about turning, Lewis about the SE5a's ability to manage the fight always staying above. Both have respect for the DR1 and later DVII, Lewis writes a discussion between Cundall and another Camel pilot discussing how impossible it was to fight a good pilot in a DVII.

I don't think the DVII is that bad, it handles very nicely, second only to the SE5a in my opinion but with the BMW engine its better than the SE5a. The stock DVII needs the Diiiau. The current Albatros handle too nicely, make them more pitch sensitive and poor rolling then the benefits of the DVII will become apparent.
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#32 gavagai

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Posted 09 August 2012 - 21:48

Well, that's just the thing about the D.VII (and when I say D.VII, I mean the Mercedes powered one): it is pitch sensitive and rolls poorly!
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#33 Scott_Steiner

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Posted 10 August 2012 - 00:42

Like a lot of other German aces, he put up an impressive string of kills in the Albatros, and eventually bought it in the ace-killer, the Fokker Dr.1.

Not contradicting your post, just adding that he pretty much bought it in the Albatross as well. To an Fe2 no less.
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#34 gavagai

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Posted 10 August 2012 - 00:53

MvR was probably shot down by Fe2 (in 1917), too.
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#35 Chill31

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Posted 22 January 2013 - 21:05

I am as eager as the next guy to have some FM changes, but there is a reason I dont waste time thinking about them anymore…
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#36 Browning

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Posted 22 January 2013 - 21:15

The following is meant as a discussion piece and doesn't actually prove anything. It is merely my opinion based on the best of my knowledge at the present moment. While feedback is much appreciated (good or bad), please read this in the spirit its intended.




Why the Albatros and Pfalz speeds can never be fixed.

In older flight sims, all aspects of an aircrafts performance were set independently. The developer set the maximum speed, rate of climb, roll rates, times to turn and many other variables to match historical data. If a plane was too slow, it was easy to adjust its maximum speed without affecting other performance indicators. This meant that developers could create aircraft that exactly match the performance from known flight test but left the aircraft feeling 'wooden'. These aircraft weren't being controlled by mathematical models but by spreadsheets.

With ROF, things are very different. In ROF, the developers create an exact aerodynamical model of the aircraft and give it its historical power output. The speed or rate of turn of an aircraft at any point in the sim isn't taken from a spreadsheet like older flight sims but dynamically calculated by applying state of the art mathematical models to the aerodynamical model/power output for the given aircraft under the atmospheric conditions present in the game. The performance of a Camel or Fokker D.VII in ROF isn't based on some dodgy flight test but calculated by advanced mathematics. That these figures come out so close to what is expected is an example of how good today’s aerodynamical modelling is.

But of course there are some problems with this hologistical approach. When the mathematical models produce performance which doesn't match historical records, little can be done to change it. Little tweaks can be made to the aerodynamical model of an aircraft without affecting historical accuracy but increasing one variable almost invariably causes a decrease in another. Tweaking the CL of a wing to produce more lift (and a tighter turn) also produces more drag and reduces the maximum speed. Tweaking the pitch of the propeller to increase maximum speed will decrease acceleration and rate of climb. The 777 developers do an amazing job tweaking the aerodynamic models to match what we know of these aircraft but they can only do so much.

One area we see a large divergence between the expected and the actual in ROF is in the unexpectedly low maximum speeds of thin high camber wing German aircraft (Albatros Ds and Pfalz D.IIIa). Official flight trials conducted at the First Fighter Completion at Adlershof between 21 Jan and 12 Feb 1918, gave the Albatros D.Va 180ps D.IIIau a level speed of 186km/h (116mph) and the Pfalz D.IIIa 180ps D.IIIau a level speed of 185km/h (115mph). While our versions are fitted with the Mercedes D.IIIa engine, they still should do a lot better than the 103mph of the present Albatros D.Va.

So what is wrong? The thin high camber wing is an aeronautical anomaly found briefly for a couple of years during the middle of WW1. Theoretically these planforms offered very high lift for low drag but even at the time, there was suspicion their performance would not match theoretical results.

NACA Report 279, Page 455 - Discussing the Albatros wing planform
“It therefore follows that very high lifts on highly cambered sections found in tests at moderate Reynolds Numbers should be viewed with suspicion since it is unlikely that they can be realized at full scale.”

We now know these extinct wing planforms weren't the miracles they were thought to be. We know they weren't high-lift low-drag, but did they actually produce the high CL's predicted and with it high drag, or did they perform more like other thin wings and produce lower CL numbers but lower drag. As these planforms are dinosaurs on the edge of mathematical understanding, we're still not sure.

In ROF, the current mathematical models assume they do produce high-lift and high-drag and as a result we have a Pfalz D.IIIa which will out turn a Fokker D.VII but can't come close to its historical maximum speed. The less cambered wing of the Albatros, while not producing the level of distortion of the Pfalz D.IIIa still produces too much lift and too much drag and hence can't reach historical speeds.

Unfortunately, this really leaves 777 with no way to fix the problem. Other than make unhistorical changes to the thin high camber planforms which would open a can of worms and most certainly not be in the best interest of the game, there is little that can be done. Unless our knowledge of how these wings performed suddenly increases and with it the mathematical models to simulate it, we're stuck with slow Albatros and Pfalz

Spoon 8-)


Where is your evidence for any of this?
Have you seen the code RoF uses? If not, then this is all wild speculation.
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#37 hq_Jorri

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Posted 22 January 2013 - 21:30

I would still like a reply from Petrovich on this :)
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#38 J5_Rumey

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Posted 22 January 2013 - 22:04

I am as eager as the next guy to have some FM changes, but there is a reason I dont waste time thinking about them anymore…


:cry: What does it mean precious?
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#39 gavagai

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Posted 22 January 2013 - 22:30

Because they don't happen.
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#40 hq_Jorri

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Posted 22 January 2013 - 22:30

Well at least we can tell our children about an age where it did happen :)
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