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#281 Kwiatek

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Posted 19 February 2011 - 01:35

So far you have provided no data that shows the E.III turns better but the data you provided prooved your point wrong. Yes, the data YOU provided. Do I need to repeat it? :roll: Talking about objective judgement are we? :lol:

I dont need to prove that EIII turn better then Airco or Dh2 in ROF beacuse you and most interested know that someone did it before me. Mig77 made turn time comparison between these planes - EIII - 14 sec, DH-2 - 15.5 sec. Online matches clearly confirm that EIII turns better then DH2 and even little better then N11.


Also i dont see any my proves which confirmed that EIII should turn better then Airco or N11. What i rather proved that EIII shoudn't turn better then Airco and N11 and moreover it shoudln't be such easy plane to fly like now in ROF it is.

Interesting is also that both Windsock and Profile claim DH2 maximum speed for 93 mph ( 149 km/h) which is faster then maxiumum speed of EIII - 87,5 mph ( 140 km/h). So it looks that DH2 biplane was faster then EIII monoplane - its also mean that Dh2 wasn't so dragy plane comparing to EIII. So DH-2 was even faster, had lower wing loading and push engine-prop. So what is a reason that EIII should turn better? I think that at least DH2 shoudn't turn worse and i think it is honest assessment of the situation.

Also some more about EIII:

"Fokker E. III quickly became obsolete machine. Its main advantage over Allied aircraft entered in the Military at the beginning of 1916 years was the use of the synchronized machine gun. After appeard the French and British Nieuport 11 Airco DH.2, Fokker E. III began to withdraw from the western front and move to the less responsible sections.

The reason for early withdrawal Fokker E. III was rooted in the use of aerodynamic characteristics of the airfoil, which had a low critical angle of attack. As a result, air stream early separation from wing and decrease the lift - which limited so necessary in fighter maneuverability."

Tomasz Goworek: Samoloty myśliwskie pierwszej wojny światowej. Warszawa: Wydawnictwo Komunikacji i Łączności, 1981

You can feel free and go proove me wrong, I asked you to do so pages earlier and thus far you have failed.

It is your point of view (avatar), but surly here are people who see it other way.
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#282 gavagai

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Posted 19 February 2011 - 02:34

No Kwiatek, Von Huetz said that your data showed the opposite of your intention, which was to prove that the DH2 should have a better sustained turn than the E.III.

This will be my last post on this topic. Let's assume a number of things. Let's assume that thrust is equal because the two aircraft have the same hp, and let's assume that their wings had similar efficiency, etc. We'll just work with what we know.

Here are the wingloading figures for the E.III and DH2 at takeoff weight:

E.III: 40.1 kg/m^2

D.H.2: 30.4 kg/m^2

% difference = (a-b)/average * 100 = 27% in favor of the DH2

Now, let's go back to the interference caused by the arrangement of the DH2's wings. We wont even worry about the double bay struts and the bird cage accoutrements behind them.

You told us that the DH2 gap:chord ratio was 1:1, and Mig found that the angle of incidence was 3 degrees (from profile publications)

Image

Judging from the above, we'll conclude that the DH2's wings only provided 80% of the lift of a monoplane with the same wing area. Therefore,

The DH2's wing area is 21.5m^2 * 0.80 = 17.2m^2.

Now we'll scale the wingloading with this adjusted figure:

653kg / 17.2m^2 = 38.0 kg/m^2

Suddenly we're very close to the wingloading of the E.III. In fact, with this adjusted figure, the % difference between their wingloading is 5%.

What about lift/drag? I'll throw you a bone and we'll use the 4 degree angle of incidence value because the chart doesn't include 3 degrees.

The chart says that the DH2 biplane would only generate 79.2% of the lift/drag of a monoplane. How much more drag would be created to create 100% of the lift?

lift/drag = .792

drag = lift/.792 = 1/.792 = 1.26 times as much drag as the monoplane, or 26% more drag for the same amount of lift! And the loaded weight of the DH2 was slightly heavier than the E.III.

So there you have it. I've been around flight sims long enough to know that a big advantage in thrust:drag can have a huge effect on relative sustained turn rates, especially when the difference in wingloading is as small as 5%.

—————

Now, go home and chew on that! :mrgreen:
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#283 Huetz

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Posted 19 February 2011 - 02:42

Of course it should read DH2, not E.III in the previous post, corrected.

Anyway, at no point a clear advantage (or an at least definate one) could be seen for the DH2 when it comes to turn. You of course played the pusher configuration card,but I have never seen nor heard of any scientifically definate source, that this configuration affects the turnrate in a significantly advantageous way. It's not like the DH2 was designed out of liking of the configuration but out of necessity.

In any case, my point of view does not come from my avatar but since you keep bringing it up, I'll do you a favor: here's a complete list of my "agenda" for ROF FMs (in no particular order):

Fix:

D.II (review overall)
D.III (stall, speed for the OAW variant)
D.Va (stall, speed)
D.VII/F (adverse yaw - roll, stall)
D.IIIa (stall)
Camel (speed)
Dr1 (speed)
N28 (stall, initial turn)
N17 (roll)
SE5 (stall speed)
Dolphin (speed)
Pup (climb, review speed)


In the end Kwiatek,you can't just pick parts of data or a source and ignore the unpleasant (for you) rest. You also can't just jump to the conclusion that the E.III performs too good just because it is comparably stable to flight reports and that's why it turns too good according to your claims. It is not twitchy enough in calm weather conditions maybe, but the fact is it does reflect all of the reported advantages and disadvantages (within the sim's limitations, unfortunately) in even the slightes turbulence, wind and with a realistic fuel setting. I also asked you to check a plane's FM based on a realistic setting before already on various topics (no, 1000m, 20-40% fuel and no turbulence is not realistic).

I doubt the Dev team designs those a/c for little fuel conditions and it's obvious why they dont do so: Because it is not relevant or realistic when looking at the RL conditions those planes were used at.

Kwiatek, it was the same on any data topic I saw you frequent so far: you cry foul, you argue about something tested in wrong conditions or based on doubtable data, do no research about features or flaws of an airframe or design(!) and jump to conclusions based on calculations you made ignoring all of the above. Once it goes wrong you either disappear for a while to then be all over another topic or you argue your last straw to death. Nothing personal but you are not doing the community or the sim any good by this conduct. Some of the methods above maybe were sufficient for IL2, but they are not sufficient enough for RoF.

As I have stated earlier,(PLEASE!) find some definate source for your claims and then come back to share and proove me wrong. Right now, there is no point to this.
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#284 Kwiatek

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Posted 19 February 2011 - 02:55

empty post
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#285 Kwiatek

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Posted 19 February 2011 - 02:59

The chart says that the DH2 biplane would only generate 79.2% of the lift/drag of a monoplane. How much more drag would be created to create 100% of the lift?

lift/drag = .792

drag = lift/.792 = 1/.792 = 1.26 times as much drag as the E.III, or 26% more drag for the same amount of lift! And the loaded weight of the DH2 was slightly heavier than the E.III.

So there you have it. I've been around flight sims long enough to know that a big advantage in thrust:drag can have a huge effect on relative sustained turn rates, especially when the difference in wingloading is as small as 5%.

—————

Now, go home and chew on that! :mrgreen:

Well im home so i dont need to go anywhere.

As you said before it is not such simple like now you try to show :)

You get lift/drag for 4 deg angle of attack which is not accurate for turning. In steep turn angle of attack is much higher - more then 10 deg. You see then when angle of attack is rising lift to drag ratio in biplane is closing to monoplane. I think above 10 deg AoA it would be about 90%. So you just get wrong data - rather for shallow climb performacne not turn.

The same is with lift generation - with higher angle of attack % of lift in biplane is more closer to monoplane then with lower AoA.

As you could check also according to avalible data DH2 (which you claim had much worse lift/drag ratio) was faster in level then EIII.

Also you know EIII wing was not also such good efficently in generating lift. You know it had moveable parts of wings by warping and in hard turn you need to coordinate it really. Moreover we dont have detailed info about wing profile characteristic ( Clmax and critical angle of attack)

Also you still ignore fact that push engine prop will give some adventage in turn.

So what im trying to say from begining is that at least EIII shouldn't turn better then DH2 and also it shouldnt be such easy to fly like now in ROF. It is too stable and stall free now.

Regarding only turn time i dunno if just EIII is too good or DH2 is too weak in these.

And it is also interesting why DH2 turn rate was changed to worse before final?
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#286 Huetz

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Posted 19 February 2011 - 03:28

Also you still ignore fact that push engine prop will give some adventage in turn.
*sigh*

One last time:

See above, there is no scientifically relevant data on this claim, thus pure assumption when only regarding turnrate.

You get lift/drag for 4 deg angle of attack which is not accurate for turning. In steep turn angle of attack is much higher - more then 10 deg. You see then when angle of attack is rising lift to drag ratio in biplane is closing to monoplane. I think above 10 deg AoA it would be about 90%. So you just get wrong data - rather for shallow climb performacne not turn

Same calculation with 10°:

1/0.87 = 1.149

So that is still ~15% more drag for 10° and ~11% for >90% effectiveness. If you test the E.III against the DH2 in sustained turn, the difference is comparably small. If you then test the E.III again against the DH2, you will also notice that the DH2 has a slight edge in turn as long as it has more energy before reaching cAoA.

So:

Regarding only turn time i dunno if just EIII is too good or DH2 is too weak in these.

Neither of the two, see above.

For your last point: it was not the turnrate of the DH2 that was changed in open beta afaik, but the overall performance of the plane that did not match historical data.
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#287 Chill31

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Posted 19 February 2011 - 04:11

edit: gavagis math works out right. My bad.

Turn rate aside, my own thoughts on the Eindecker are that it is too docile with regard to stall. The DH2 will drop a wing and wallow, but the Eindecker doesnt really show significant stall characteristics. I think it would be a different plane if you actually had the ability to fly it outside of its "safe" flying regime as you can with the DH2. I dont know why it is that only German planes have such benign stalls. Hopefully up for correcting in the future.
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#288 Chill31

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Posted 19 February 2011 - 04:26

I really dont see how the Dh2 can be faster than the Eindecker aerodynamically. DH2 has as many or more bracing wires, plus the frontal area of a biplane configuration. I'm not one to scoff the data, but given the research I did in trying to test flight models, I found that data is varied and poorly documented in most cases. It is difficult to establish conditions under which the data captured. Based on what I learned in doing that research, I would push for what I call historical integrity as opposed to sticking directly to the ambiguous (unclear) data. Historical integrity would evaluate the data and historical accounts and align them to build the most representative model of whatever it is.

Like Kwiatek said, higher AoA does give less disadvantage to the DH2 where turn performance there might be very close between the 2 planes, but I would still favor the Eindecker to have a slight edge. The main disadvantage I can see with the Eindecker is that it is a monoplane with relatively (to the Dh2) weaker wings, so the DH2 should be able to dive roll loop where the Eindecker would lose its wings.
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#289 catchov

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Posted 19 February 2011 - 04:50

my own thoughts on the Eindecker are that it is too docile with regard to stall. The DH2 will drop a wing and wallow, but the Eindecker doesnt really show significant stall characteristics. I think it would be a different plane if you actually had the ability to fly it outside of its "safe" flying regime as you can with the DH2. I dont know why it is that only German planes have such benign stalls. Hopefully up for correcting in the future.

+1
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#290 gavagai

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Posted 19 February 2011 - 05:30

Along the right track, but I'm not sure thats quite the right math. 30.4 kg.m^2 is the amount of lift that the wings must generate to make a DH2 fly.

On the subject of lift…

I would think the units for lift would be a force, like a Newton? kg/m^2 doesn't make sense as a unit of lift.
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#291 Chill31

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Posted 19 February 2011 - 06:21

Lift has to equal (or exceed) weight for the plane to fly. So lift could be measured in Kg, the same as the aircraft weight. If we divide the amount of lift required by the wing area, you get lift (in Kg) per m^2 (kg/m^2).
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#292 gavagai

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Posted 19 February 2011 - 06:54

Lift has to equal (or exceed) weight for the plane to fly. So lift could be measured in Kg, the same as the aircraft weight. If we divide the amount of lift required by the wing area, you get lift (in Kg) per m^2 (kg/m^2).

I think I'm following you…

Here is what I was about to edit into my previous post (read carefully):

————

One equation for lift:

L = .5 * air density(kg/m^3) * (m/s)^2 * planform area m^2 * lift coefficient at AoA

The unit of lift there is a Newton. And the equation also tells me that lift is proportional to planform area. So, other things being equal…

.8L1 = L2

L1 = A^2

L2 = .8A^2

Therefore, we subsitute 80% of the wing area for 80% of the lift for a scaled wingloading figure to make a very loose, idealized comparison of a monoplane to a biplane. :)

—————-

So, by my own logic there, I have the same conclusion as you that we can substitute area for lift. The difference is that you're treating the wingloading figure as both a simple ratio for weight/lift, and as the lifting force itself.

30.4 kg.m^2 is the amount of lift that the wings must generate to make a DH2 fly

maybe "force per unit area of lift?" would have been better?

lift could be measured in Kg, the same as the aircraft weight.

So which is it? We can't use both definitions at the same time.
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#293 Chill31

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Posted 19 February 2011 - 09:04

First, my math was the bad math. 1/.8 is 1.25 not 1.2…heh, some days. As it works out, both ways get you to 38kg/m^2

2) With regard to Force and its status in physics, yes, force should be measured in Newtons (when using the metric system). However, you can cancel the acceleration of gravity and compare Kg directly. Though it wont be the correct unit for use in further equations, it will provide the correct ratios when comparing aircraft. So is Lift measured in Kg? technically, no. Practically, yes.

3) In the Lift equation, S (wing area) is not S^2. The unit of S is squared, but S
itself is not squared.
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#294 gavagai

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Posted 19 February 2011 - 14:08

True, I should have written that as m^2, or just as A.

Good conversation. :)

P.S. I'd also like to see some of the German aircraft stall more sharply, but the Pfalz D.XII, Dr.1 and D.VIII seem ok.
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#295 ImPeRaToR

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Posted 21 February 2011 - 08:01

Me too, the Albatros D.III is also reasonable imo.
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#296 meezer3

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  • Posts: 99

Posted 29 April 2011 - 15:22

I apologize if I'm starting a different chain of thought, but I think this is on topic. When I first started playing RoF a year or so ago, I thought that some of the flight models were off.

For example, while reading through Osprey's book on No.56 squadron and the SE5a vs DV, there are a lot of claims made by pilots and the historians that the SE5a was an excellent plane that outclassed all other Central Power aircraft, and gave the DVII a serious run for it's money. When I began playing RoF, I could barely keep the SE5a in the air, but could shoot them down while flying any Albatros or Pfalz DIII. I believe I incorrectly thought then that the SE5a must be misrepresented in the game.

After playing the game almost nightly for months and not really touching the SE5a, and learning to squeeze every bit of performance out of planes like the DH2, I have revisited the SE5a and was blown away by it. Not only did it allow for a generous sustained turn, it out climbs and out dives a lot of the competition.

My thinking is that it was hard for me to judge the flight model, because it was me, the pilot who was inferior, and not the plane. The central power planes, (aside from the Dr1,) seem to be super forgiving and able to turn for long periods of time. However, as good (easy?) as the Albatros and Fokker DVII are to fly, they seem to be more restrictive. I feel stupid for judging the SE5a as a lousy aircraft because it didn't seem stable in my amateur hands. I now see that there is a difference between a plane that is doggedly stable and hard to stall, and one that is on the edge of being out of control. The SE5a simply requires a better pilot to fly, but once a person can fly it, it becomes such a dominant force. I find now, with a better sense of how to push an aircraft close to the edge (thanks to flying the DH2 for many hours) the SE5a becomes a blank canvas for me to paint whatever battle strategy I want. I can cook up Albatros any way I please!

I also suspect that the SE5a is a much better gun platform because of its rather pronounced dihedral wings. Correct me if I'm wrong, but I sense that the dihedral makes the SE5a more stable in a turn that it can maintain, than a Fokker DVII in nearly any turn. After my latest dogfight in the SE5a, I felt like the plane barely yaws or bounces in a turn, and while I can turn and burn endlessly in a DVII, I'm always having to make micro-corrections to keep my cross hairs on the enemy.

Do the dihedral wings help the SE5a keep its directed position better than flat wings that let air "spill" out from under them?

Sorry for the long post. I guess my main thought to this thread is that flight models can only be judged by a pilot when the proper experience to use the crate's maximum performance has been obtained. I still don't fly the Dr1 and the Camel because, frankly, I'm not ready for it. I'm just glad I understand that now, and I thought I'd pass this along to greener pilots to not write off "twitchy" aircraft as bad crates.
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#297 DidNotFinish

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Posted 01 May 2011 - 15:56

Same here. I remember when the SE5a was added to ROF, I bought it right away but I could barely fly it. It spun too much and I could almost never get it out of a stall. It was difficult to turn without going into a spin or losing altitude. And I would kill the engine all the time due to over-revving. Now, much later, I can almost always get out of a spin, I can turn all day because now I know the correct use of the rudder in a turn, and over-revving isn't a problem anymore because I've learned to throttle back in a dive. It's one of the easiest planes for me to fly now.

Now the Dr.1 is a different story! :P
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#298 Brandiment

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Posted 13 May 2011 - 00:14

Gotha tends to dip heavy and stall even at cruising speeds
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#299 LukeFF

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Posted 17 May 2011 - 04:51

Some Nieuport 28 data. Dunno if it's already been posted or not:

http://www.airminded.net/n28/n28.html" onclick="window.open(this.href);return false;">http://www.airminded.net/n28/n28.html
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#300 Carrick58

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Posted 05 September 2011 - 18:09

I agree with the turning statements about the Sopwith Camel. Everything I ever read indicates that the right turn was an incredible turn rate with a loss of altitude because of of Gyroscopic forces. The left turn was said to be slower ( I would assume that loss of height also occurred because all other aircraft lose height when turning). I have never read anything indicating that a Camel was a good fighter above Low level. In the game the camel is Great at mid and High level and can Ram ur aircraft ( during Multi player) with its wheels and stay intact as u crumple.
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#301 Stiffy

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Posted 07 September 2011 - 22:19

sorry if this has been covered but havent quite waded through all the 30 pages of this thread!…

I've seen alot about the DH2 in game being the late model… but why then does it only have 100hp?

Shouldn't it have 110hp if it is a late model?… and where has the figure of 130kmph come from? Surely the 110hp was faster than the early DH2 not slower? (10hp would more than counter any drag from a teardrop tank!) Just curious as to the source for the data… happy to admit i'm wrong if people know better.
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#302 Stiffy

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Posted 07 September 2011 - 22:42

So far this is the only data I have found for the later DH2. I don't speak russian I'm afraid but I'm pretty sure this says 110hp 148kph

http://flyingmachine.../Craft25435.htm" onclick="window.open(this.href);return false;">http://flyingmachine.../Craft25435.htm

if it supposed to be the 100hp (early) then it should be 150kph…

so where has 130kph come from?
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#303 Stiffy

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Posted 07 September 2011 - 23:18

ok looked it up in the windsock publication (one that rof uses for data) and yes… rof data is way out for some reason. Windsock has no data for ground level for the 26 gallon tank variant (the one in game) but ROF is way out at other heights and has clearly estimated a bad ground level speed because of it!

Here is the ROF data followed by the actual speeds for the 20 gallon and 26 gallon variants


Sea level 130 149 ???
2000m 118 138 126
3000m 110 123 113

So is actually about right at high altitude but waaaaaay to slow at low altitude. Somewhere around 140-145 would be more likely surely… if any differnce at all. surprised they have made this error as they cite windsock as a key source for their data.
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#304 gavagai

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Posted 08 September 2011 - 10:02

You are comparing IAS and TAS.
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#305 Stiffy

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Posted 08 September 2011 - 10:57

You are comparing IAS and TAS.


Irrelevant. IAS and TAS are the same at ground level. 130 is just plain wrong, made up , false and innacurate…. really not sure why people can't accept this… do you all hate british planes or something? :O
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#306 Stiffy

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Posted 08 September 2011 - 16:12

Anyway… after my last post I can see that I'm skating around the edges of ranting and don't want to turn into a maniac flamer. :) So what I'd really like is for the devs to just review the speeds for the DH2. ROF I think have the EII at 142 IAS - sea level. We know that the early DH2 had an IAS AND TAS of 150 at sea level (there are always the same at sea level at presure of 1 atmosphere). So taking windsock data into account I think that 130 at sea level for the later fuel tank may be an underestimation (and it is an estimation… not a calculation due to poor availability of data).

I'd also like to see the DH2 a little more twitchy and a better sustained turner as it was described by the pilots of the time (the stalls in turns were due to inexperience not the aircraft). Having said that I would also like the bad points… an unstable re-bored engine which occasionally fires a cylinder through the tail booms, the top wing catching fire when the tank is punctured. Accounts also describe the torque as being very bad causing severe lurching when blipping during landing and needed nearly full rudder to stay straight in level flight. C'mon devs, make this into the dangerous, challenging and yet brilliant aircraft it really was. As it stands its a bit dull! ;)
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#307 =IRFC=AirBiscuit

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Posted 12 September 2011 - 14:58

Yea, it kinda flies like a modern day ultralight. Docile, and worthless in combat :lol:
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=IRFC=Air Biscuit

http://quetoo.org


#308 MattM

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Posted 12 September 2011 - 16:00

Yeah, the DH2 is definately one of the most underperforming planes in ROF, at low altitude.

It reaches about 132 km/h at ground-level. Which is ~10 % slower than it should be. I've never found a source that would support a <140 km/h speed at ground level.

The climb is actually correct.
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#309 Baal2

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Posted 10 October 2011 - 15:00

The spad 13 had a fuel dumping valve located under the tank, could we have this feature modeled?
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#310 Brandiment

Brandiment
  • Posts: 271

Posted 21 November 2011 - 15:43

Why. do you want to accidently tap it and dump all of your fuel on the german lines?
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#311 piecost

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  • Posts: 1318

Posted 15 December 2011 - 19:57

Aeronautical Journal 1920

Note on an Empirical Formula on Aeroplane Strength

[maximum load factor: SE5a, Pup, Camel, Dolphin, Snipe, RE8, HP-0400, Bristol Fighter]

Attached Files


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#312 The_Mad_Prof

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Posted 28 March 2012 - 18:18

I have thoroughly enjoyed flying ROF and still do. But I am slightly taken aback at the supposition that finding accurate data and putting it into the simulation will actually produce a accurate flying model of a particular aircraft.

To truely replicate the behaviour of these aircraft you would have to build the real thing using authentic materials that were on the originals - then fly them in combat scenarios that the real ones faced. Any flight model produced would match what happened to the real life replicated aircraft.

Unfortuately the flight models in ROF do not match such experiments. There is a company in New Zealand that has just done this. See website:

http://thevintageavi...age-aviator-ltd" onclick="window.open(this.href);return false;">http://thevintageavi....co.nz/vintage- … viator-ltd

UK channel 5 has covered this subject in a recent documentary showing this company in action. It is certanly worth viewing.

One example the SE5A could totally outfly the Albertros DV in real life. This is totally the opposite in ROF. The SE5A is far ahead of the german plane (historical accounts confirm this - listen to the archive accounts of the pilots that flew them in WWI and the modern day replica pilots from this company).

If you really really want a true to life simulation then you need to talk to these guys and revise your models accordingly. You may be putting in authentic data but the results do not match what should happen.
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#313 Lieste

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  • Posts: 226

Posted 13 May 2012 - 05:26

You know it's not so simple as that kwiatek; don't play dumb. The DH2 is a double bay biplane, its wings are of equal span and chord, and they are unstaggered and close together. None of those factors lend themselves to efficiency, but you knew that already.


Actually in common with almost all biplanes, the DH2 has staggered wings.

That the leading edges are "vertically aligned" is irrelevant, as aerodynamically it is the zero-lift condition that is important for this geometry - for this you need the nose down by what ever the incidence value is, plus whatever the influence of camber is for the section.

This is typically between 5 and 10 degrees - most often towards the higher end, and is therefore of some significance. The same consideration is applied to staggered multiplanes as well, but the additional improving influence becomes less (not least because gap closes faster for forward stagger).
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#314 Lieste

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  • Posts: 226

Posted 13 May 2012 - 14:10

One item that does see considerable variation is the ground roll - we see no movement until power is very near to full, while the Albatros is noted as 'moving at a brisk walk' while held at idle at around 500rpm.

Others also have reported friction much less than we have (the wheel bearings eliminate any significant 'stickion' between tyre and ground, and the tail-skid doesn't have much frictional force (unless held down forcibly, and even then not sufficient to absolutely prevent a ground loop).

If it is supposed to represent 'chocks/mechanics holding down the airframe' then this should be made a distinct and different effect, otherwise the amount of rolling resistance to motion, and/or thrust at low RPM and low speed needs to be looked at.
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#315 Wykletypl

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Posted 23 January 2013 - 15:54

Speaking of Flight Models, let me ask you this for 'Quick Mission' mode - Is every single scout set for 'Novice' always diving to the ground and stay at 100 meters for us to hunt him down and shoot him?
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#316 Wykletypl

Wykletypl
  • Posts: 538

Posted 28 January 2013 - 22:58

What is landing procedure like when you have all engine options (mixture, radiator and so on) set on 'automatic'? Well, all that happens is: You land, you crash, you land, you crash, you land… And You crash. Occasionally you will succesfully land by being extremely patient and careful with controls. And of course make sure you are landing on REALLY flat field.
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#317 boingk

boingk
  • Posts: 8

Posted 04 February 2013 - 14:20

Anyone notice the E.III breaking up very easily? I'm piloting against Ace level E.III's in an N.11 and mostly they just break up due to turning forces?

- boingk

Liet - the lowspeed characteristics seem fitting with my own light aircraft, a Continental A-65-8 powered twin seater with 30ft wingspan and MTOW of 515kg. It turns a 72" prop at 700rpm idle and needs around 1100rpm to dislodge it from grass, 1300rpm if it is thick grass or soft ground. I would say it flies just about as well as an early WWI fighter, with 600fpm climb and level speed at sea level 80kt/150kmh, and has comparable propellor thrust staistics compared to weight.

As for landing with everything set to automatic… you lower engine speed to reduce flight speed, then descend. On final approach use engine to dictate height and not elevator, then flare gently on landing. Everything else is done by the computer.
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#318 pomjon

pomjon
  • Posts: 15

Posted 26 May 2013 - 23:20

One thing I've noticed is that many of the models in ROF do not fly with any angle of attack at full throttle.

The SE5a for one example, if you fly level with the throttle full open, the wing is perfectly parallel to the ground and the nose actually points down at the ground. Many other aircraft do this. This is simply not how aircraft fly. Physics of flight and the generation of lift require an angle of attack. That being difference in angle between the direction of the body of the wing, and the direction of travel. IE, the aircraft flies forwards, the wing is pointed slightly upwards. The slower the aircraft, moves the greater the angle of attack (the aircraft's nose will start to pitch upwards) but even when the aircraft is flying flat out, the fuselage would be parallel with the ground and thus the wing angled slight upwards. The physical models are not wrong, just how they are flying.
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#319 Tom-Cundall

Tom-Cundall
  • Posts: 5549

Posted 27 May 2013 - 08:13

I believe that you only need an angle of attack for planes with symmetrical wing cross sections e.g. P51 (demonstrated with a hand out of a car window and changing it's angle of attack)

For the SE5a (and all of the aircraft in ROF) the shape of the wing's cross section means that air travels further across the top of the wing compared to the underside. This creates a static pressure differential generating lift even at 0 degrees AoA.

Image

That said increased AoA will increase lift up until the point of stall:

Image

But the same effect is achieved with 0 AoA and increased air speed since the pressure differential increases.

(Technically there is some AoA built into the wing - it is the angle from the trailing edge to the highest point of the leading edge)

Incidentally the SE5a did fly at a nose down attitude in level flight - this is why the gunsights and guns were aligned with the wings and offset c5 degrees from the angle of the fuselage. A game limitation means that in ROF the guns and sights fire along the line of the fuselage- this is acknowledged as incorrect by the developers.

POLL: Should 777 fix the misaligned aldis on the SE5a/N11?
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#320 BssSniper

BssSniper
  • Posts: 4

Posted 01 July 2013 - 01:11

I believe that you only need an angle of attack for planes with symmetrical wing cross sections e.g. P51 (demonstrated with a hand out of a car window and changing it's angle of attack)

For the SE5a (and all of the aircraft in ROF) the shape of the wing's cross section means that air travels further across the top of the wing compared to the underside. This creates a static pressure differential generating lift even at 0 degrees AoA.

Image

That said increased AoA will increase lift up until the point of stall:

Image

But the same effect is achieved with 0 AoA and increased air speed since the pressure differential increases.

(Technically there is some AoA built into the wing - it is the angle from the trailing edge to the highest point of the leading edge)

Incidentally the SE5a did fly at a nose down attitude in level flight - this is why the gunsights and guns were aligned with the wings and offset c5 degrees from the angle of the fuselage. A game limitation means that in ROF the guns and sights fire along the line of the fuselage- this is acknowledged as incorrect by the developers.

POLL: Should 777 fix the misaligned aldis on the SE5a/N11?


There are quite a few aircraft that fly nose down at cruise. Also the example graphics you posted and talked about are the basis of the theory of lift. Not sure what you're trying to get at.
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