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RoF test flight data


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#1 MiG-77

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Posted 10 August 2010 - 06:22

I have made series of tests with game planes during last half year or so. You should remember that these are just my test results and may not be "the thruth", but they should close enought to be used as general quide of plane perfomances.

General test methods used: No wind/turbulence so those dont affect test, warmed up engine on. Everything else in realistic settings. Speeds, etc looked from simple gauges. In climb test, climb started from plane max speed at deck (flying just above trees). In turn tests, turn speed I just tested with 10km/h intervals so actual best might be ie 134,55467km/h ;) Also those turns are sustained turns and I made couple of circles before timing started.

Attached File  Climb_Test.jpg   110.02KB   1321 downloads
Attached File  RoF_acceleration.jpg   112.2KB   1320 downloads
Attached File  Turn_tests.jpg   75.74KB   1322 downloads
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#2 Tom-Cundall

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Posted 10 August 2010 - 08:50

Nice work - thanks Mig.
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#3 hq_Jorri

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Posted 10 August 2010 - 10:40

Brilliant :) now you've opened up shop I hope they served the community as well as they helped us.
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#4 MiG-77

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Posted 10 August 2010 - 10:41

Brilliant :) now you've opened up shop I hope they served the community as well as they helped us.

Well, you will see them first still ;)
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#5 hq_Jorri

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Posted 10 August 2010 - 11:03

I think it's great that you posted them here.
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#6 gavagai

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Posted 10 August 2010 - 13:05

I'm impressed with your sustained turn data. You really got a lot out of the Dolphin (11s!). People should also be careful with noticing the best turn speed, as even though the SE5 completes a circle in the same time as an Albatros D.Va, it cuts a much wider chunk of sky accomplishing it.
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#7 MiG-77

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Posted 10 August 2010 - 14:06

I'm impressed with your sustained turn data. You really got a lot out of the Dolphin (11s!). People should also be careful with noticing the best turn speed, as even though the SE5 completes a circle in the same time as an Albatros D.Va, it cuts a much wider chunk of sky accomplishing it.

True, planes with smaller turn speed are "better" (smaller circle) even if they have same turn rate. IE SE5a cannot get firing solution (by just doing sustained turn) to Albatros D.Va ever even if they both turn just as fast. Albatros D.Va on other hand can…

Dolphin secret just is that dont get too slow, as most do (same with SE5a and SPAD XII) ;)


BTW, if anyone has better speed for turn/climb tests, just post it here. I make new test and change results if results are better.
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#8 mike_espo

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Posted 10 August 2010 - 14:21

Great Work Mig! Thanks. :D

What about Max. Speed?
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#9 gavagai

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Posted 10 August 2010 - 14:33

That's already been done. Note that this chart is a little old, so the D.XII engine is still the Mercedes. Also note the crazy results for the Dr1 and DVIII. Image
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#10 hq_Jorri

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Posted 10 August 2010 - 14:54

Several charts have been made on top speed. I know one of them was just grabbed from the store page - I hope that's not this one.

Matt made one as well (with 100% fuel of course):

Image
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#11 brams

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Posted 10 August 2010 - 15:47

Hey the Pfalz really is dramaticly different when looking at both graphs???
Did the engine swap make such a huge differnce? WOW!
Anyways still a crappy plane… I mean…

CRAP!

:lol:
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#12 Tom-Cundall

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Posted 10 August 2010 - 16:05

Do you know if it was started at altitude to test top speed or logged whilst climbing - because fuel would be burnt in the climb (unless unlimited fuel was selected)

Not trying to be difficult just want to be clear some of these planes burn a fair wack of fuel in the time it takes to get them to 5km (16500 ft for those who don't speak European!)
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#13 MiG-77

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Posted 10 August 2010 - 16:19

Im pretty sure that test were started at altitude. It just takes too long to climb there. Also Im pretty sure you still would not see difference in speed.
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#14 gavagai

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Posted 10 August 2010 - 17:24

Im pretty sure that test were started at altitude. It just takes too long to climb there. Also Im pretty sure you still would not see difference in speed.

At such low IAS, the difference in induced drag might cause 1-2km/h difference. :)
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#15 piecost

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Posted 21 August 2010 - 07:32

I am starting to perform some testing myself. For expedience I am using the quick mission builder with wind 0m/s, turbulence 0m/s, weather clear. The wind is also selected off in the difficulty settings. I am performing repeated tests (climbs and glides at constant Indicated airspeed) over many separate quick missions. Do you know if the atmosphere is consistent between them? Should I be using the full mission editor with a time and date set to match the International Standard Atmosphere?

Further, I am varying the fuel and ammo load to fly at light and heavy weights. Can anyone tell me the assumptions for pilot mass, fuel density, oil density and ammunition mass ?
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#16 piecost

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Posted 23 August 2010 - 18:55

Stall Tests

A test was carried out to determine the maximum lift coefficient of each aircraft.

The tests used a Logitec Wingman Extreme joystick and Simped F16 rudder pedals with the default joystick & rudder responses. Tests were carried out for light and heavy weights:

100% Fuel + 100% Ammo (no bombs)
5% fuel + 0% ammo (no bombs)

The large gauges were not visible for 0% fuel, so the fuel level was set to 5%. A Post-it was stuck to the monitor with 1kph graduations marked. All speeds are IAS taken from the large gauge.

The following mission settings were used:

Quick mission: Skirmish: Lille
Altitude: 3000m
Time: 12:00
Clouds: 5000m
Wind: 0m/s
Turbulance: 0m/s
Weather: Clear

Each stall was repeated at least 3 times and the most consistent of the readings was taken. The results were very sensitive to pilot technique and joysick quality. I will be interested to compare with other peoples results.

The test was started in steady flight at 3000m with full throttle, mixture set to obtain maximum revs and radiator open. The throttle was then closed, or the mixture set to full rich on rotaries with no throttle control. No effort was made to climb back to 3000m between stalls. The rate of deceleration to stall speed has a large effect on the measured speed and so once the throttle was closed the stick was progressively pulled aft to slowly decelerate without a noticeable change in height. Care was needed to ensure neutral ailerons and rudder.

Some aircraft suffered from wing rock as the stall was approached (Nieuport 11 , Albatross DII, DVa and Fokker DVIII), this prevented an accurate assessment of the stall speed. In certain cases a clean stall break could only be achieved by decelerating rapidly enough before the rock had time to establish. This method was not consistent with the other tests. The Fokker DVII/DVIIF and Pflaz DIIIa (5%Fuel+0%Ammo) lacked sufficient elevator authority to stall when the slow deceleration method was applied. Applying up elevator from a higher speed allowed a clean stall, but was inconsistent with the slow technique. These stall figures are considered inaccurate.

The following notes were taken:


Stalls with 100% Fuel + 100% Ammo (no bombs)

Nieuport 11 - wing rock 81kph, stall at 72kph if approached fairly quickly. Stall not accurately defined. Engine overcooled.

N17 engine over-cooled

Albatross DII - defuse, no clean break

Albatross DIII - wing rock at 82kph, 72kph if approached quickly

Albatross DVa - wing rock at 81kph; decelerate quickly to avoid rock

Fokker DVII - Full aft stick trims at 79kph, estimate 76kph stall

Fokker DVIIF - Full aft stick trims at 79kph, estimate 78kph stall

Fokker DVIII - Difficult to stall cleanly due to wing rock. Any aileron provoked spin, rudder to level wings. Engine over-cooled


Stalls with 5% Fuel + 0% Ammo

Nieuport 11 wing rock at 71kph

Albatross DII - wing rock at 76kph leading to stall

Albatross DIII - wing rock at 79kph, stall at 74kph if decelerate quickly enough to get through rock

Albatross Dva - wing rock prevents accurate assessment

Fokker DVII - Full aft stick trims at at 76, estimate stall at 67kph

Fokker DVIIF - Full aft stick trims at 75, estimate stall at 74kph

Fokker DVIII - Difficult to stall cleanly, Very sensitive to smallest aileron deflection. Engine over-cooled during test

Pfalz DIIIa - Full aft stick 71kph, estimate stall

Camel - overcooled engine


The measured stall speeds are given in the attached chart for each aircraft at light and heavy weight. The orange band on the airspeed indicator is also given. This is an approximate match to the stall speed, may be in true airspeed, and does not vary with aircraft weight.

To calculate the maximum lift coefficient the; take-off weight, empty weight and wing reference area were taken from the RoF Store. The weights are given in the second chart. It was noted that the empty weight of the Dolphin looks too low at 436kg; British Aeroplanes 1914-1918 by J M Bruce gives weights for various prototypes and marks as between 612kg and 710kg. To estimate the flying weight for the aircraft with 5% Fuel + 0% Ammo (no bombs) the empty weight plus 80 kg for the pilot was taken. The weight of 5% fuel was assumed as negligible.

The last chart gives the calculated CLmax for each aeroplane.

The general trend of the aircraft at lower weight aircraft exhibiting a lower CLmax may be due to the estimation of pilot weight being too low. But it took a pilot weight of 130kg to reverse the trend. Perhaps the empty weight should include oil? The trend could also be explained by the difference in centre of gravity of the light to heavy aeroplanes. In theory, the plane with the further aft centre of gravity should achieve a higher CLmax. Experience with the Sopwith Camel suggests that RoF models impact of changing centre of gravity on the flight model. If the aeroplanes fuel and ammunition are stored aft of the centre of gravity position then the light weight corresponds to forward centre of gravity and lower CLmax. The Pfalz DIIIa cannot be stalled at low weight (assumed forward cg), but this could be due to the reduced elevator effectiveness at the lower stall speed.

The next most noticeable feature is the highest of CLmax belonging to the the Fokker DVII at low weight. This is at odds with the trend for the other aeroplanes. It was calculated based on an estimated stall speed (In-trim with stick fully aft at 76, estimated stall at 67kph – this relates to 0.4 CLmax). This should be considered as in error.

The next highest CLmax belongs to the Fokker DVIII at high weight. This should also be considered as suspect since difficulty was experienced in achieving a clean stall due to wing-rock. I would not expect any of the aircraft to exceed CLmax=1.6 and guess that it shares a CLmax similar to the DVII's.

The other aircraft seem “consistant” with known flying qualities; the Fokkers having high values and the SPAD XIII and Nieuport 28 low values. A surprise is the high maximum lift of the Pfalz DIIIa and the Pfalz DXII not being similar to the SPAD XIII.

The low CLmax for the light Dolphin is not believed and it is concluded that the RoF store empty weight is in error.

Lastly, I would expect the actual values for the CLmax to be rounded to the nearest 0.1CL since the developers will have made estimates – lacking hard data for each aircraft. It would be interesting to know if the impact of the down-force generated by the tailplane & elevator is accounted.

Attached Files


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#17 WF2

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Posted 23 August 2010 - 19:25

Fantastic data. Hope the Dev team uses it.
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#18 Kwiatek

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Posted 25 August 2010 - 10:29

It looks like that ROF interepretation of some planes in turn rate characteristic looks very dubfull.

Here is a test of performacne ROF planes by MIG-77 including turn rate:

RoF test flight data

So we have such comparison: From best turning to the worst

Albatros DII - Albatros DIII < Albatros DVa < N17 < N11 - Fokker E III < Airco DH2


And what i expect to should be:

N-11- N17-Albatros DIII < Airco DH2 < Albatros DII - Albatros DVa - Fokker E III

Actually i think ROF is far off with some planes turn rate and it doesnt match RL opinions but also technical data.
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#19 MattM

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Posted 25 August 2010 - 14:50

I think i posted this before, but anyway, here we go.

(That's TAS, full loadout, excluding bombs, manual mixture for maximum RPM, altitude throttle set to maximum without getting strange noises from the engine)

Attached Files

  • Attached File  1.jpg   142.34KB   573 downloads

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#20 Hellbender

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Posted 26 August 2010 - 07:24

True, planes with smaller turn speed are "better" (smaller circle) even if they have same turn rate.

This proves the obvious disparity between the Camel and the Dr.I and the fact that we perceive the Dr.I to be a better turner, while their turn time is identical.

The Camel can still outmaneuver the Dr.I in a climbing turn, denying the Dr.I a firing solution.
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J5_Hellbender


#21 1PL-Lucas-1Esk

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Posted 27 August 2010 - 18:28

The SPAD 13 and DH2 shall be turning to the left during the tests. The S.13 has counterclockwise prop. and DH2 is pusher type with clockwise propeller. This is why the DH2 has such a terrible turn rate.
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#22 piecost

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Posted 15 October 2010 - 13:14

Stall Tests

A repeat of my earlier test for the new Pup & Triplane. I have rounded the results to the nearest 0.1 CL as I believe the developers will have estimated CLmax to this resolution.

The Fokker DVIIf was set to be the same as the DVII

Attached Files


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#23 Kwiatek

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Posted 16 October 2010 - 11:01

Nice test Piecost.

I looked at Cl max for some planes and im no wonder that some German planes fly like a ufos. I always suspected that they have too high Clmax/critical angle of attack:

See:

Fokker DVII - 1.8 Clmax !!!
Pflaz DIIIa - 1.6 Clamx
EIII - 1.3 Clamx

I wonder how big have these planes critical angle of attack values.

Dunno about Niueports 11 and 17 - 1.4 Clamx ( looks little to high) and Niueport 28 - 0.9 Clmax look little too low.
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#24 Kwiatek

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Posted 17 October 2010 - 01:04

From my data CL max should be :

Fokker DVII - 1.38 at 16 deg. cAoA
Albatros - 1.35 at 14.5 deg. cAoA
Pflaz DIIIa - 1.58 at 16 deg. cAoA

It looks like Fokker DVII had too high Clmax value ( too low stall speed). Also im wonder about critical angle of attack. It look that all these planes ( Albatros, Pflaz DIIIa, Fokker DVII) have too high critical angle of attack.
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#25 Chill31

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Posted 17 October 2010 - 01:27

Kwiatek, what equation are you using to compute Cl max? and how are you computing the AoA?

Piecost, what equation are you using for Cl max? Also, may I ask your background? Why have you concluded that the Pfalz D3 and Fokker D7 cannot stall?
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#26 ImPeRaToR

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Posted 17 October 2010 - 08:11

From my data CL max should be :

Fokker DVII - 1.38 at 16 deg. cAoA -1.8 ingame, not that it helps much
Albatros - 1.35 at 14.5 deg. cAoA -1.4 rounded ingame
Pflaz DIIIa - 1.58 at 16 deg. cAoA -1.6 rounded ingame



Well, Albatros and Pfalz D.IIIa actually fit your calculations so they can't have a too high AoA ;)

The D.VII suffers enough as it is, if you get defeated by one of them online you are doing something wrong.
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#27 MiG-77

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Posted 17 October 2010 - 08:15

From my data CL max should be :

Fokker DVII - 1.38 at 16 deg. cAoA 18 ingame, not does it helps much
Albatros - 1.35 at 14.5 deg. cAoA (14 rounded ingame)
Pflaz DIIIa - 1.58 at 16 deg. cAoA (16 ingame)



Well, Albatros and Pfalz D.IIIa actually fit your calculations so they can't have a too high AoA ;)

Also D.VII thick göttingen airfoil had bigger cAoA than most other airfoils at the time.
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#28 ImPeRaToR

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Posted 17 October 2010 - 08:16

Forgot to add the . in my post, I blame no coffee and breakfast :)
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#29 MiG-77

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Posted 17 October 2010 - 08:56

Hmm, looking NACA data from Göttingen 282 airfoil (not sure is it D.VII airfoil, it is Dr.I tought), CL max was 1,35 @ 15deg AoA.

On other hand IE N17 airfoil (most likely Eiffel 53) show CL ~0,52 @ 10deg AoA (line is not drawed more than to 10deg). Sopwith Camel airfoil (RAF 14?) CL max ~0,545 @ 14deg AoA.
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#30 Kwiatek

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Posted 17 October 2010 - 10:36

Kwiatek, what equation are you using to compute Cl max? and how are you computing the AoA?

Piecost, what equation are you using for Cl max? Also, may I ask your background? Why have you concluded that the Pfalz D3 and Fokker D7 cannot stall?

I got some WW1 planes wing profiles with Cl,Cx polares.

And Piecost as i think just use formula to calculate Clmax depending of stall speed.

What i dont know is how critical angle of attack use planes in ROF. I dont have such data - but i suspect very high probably that planes which i mention above use too high values of critical angle of attack - thats why these planes dont have accelerated stall.

Wing profile used in FOkker DVII was the most thick of these - it reach as i wrote 1.38 Clamx at 16 deg angle of attack. Such profile cause high drag, but also it was quite gentle in stall beacuse Cl polare is quite soft droping after reach critical angle of attack comparing to other wing profiles like Pflaz DIIIA or Albatros have. So plane would be stall but very gentle when other planes will get much more nasty stall chatacteristic. As you see such aerodynamical wing characteristic such planes like Pflaz DIIIa, Albatros and Fokker DVII is confirmed by RL pilots opinion ( Pfalz and Albatros had some nasty stall characteristic and Fokker DVII had gentle stall). I would like to see the same in ROF.
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#31 Kwiatek

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Posted 17 October 2010 - 10:55

Hmm, looking NACA data from Göttingen 282 airfoil (not sure is it D.VII airfoil, it is Dr.I tought), CL max was 1,35 @ 15deg AoA.

On other hand IE N17 airfoil (most likely Eiffel 53) show CL ~0,52 @ 10deg AoA (line is not drawed more than to 10deg). Sopwith Camel airfoil (RAF 14?) CL max ~0,545 @ 14deg AoA.

Mig you got wrong data for Camel and Nieuports.
Camel used RAF 14 profile which is very close to RAF 15 ( SE5a) but little more cambered. RAF 15 (Se5a) has 1.05- 1.1 Clmax at 15 deg angle of attack. So RAF 14 would be similar.
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#32 ImPeRaToR

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Posted 17 October 2010 - 10:58

All the RL pilot accounts you mention and which you quoted in the past were always in regards to the Pfalz D.III, as far as I remember.

If you have any pilot accounts on stall characteristics on the D.IIIa or the Albatros please share them. Little if any have come up so far that support your claims of them stalling easily, besides the D.III does stall and spin easily already if you handle it too roughly. The D.Va is a different matter though.
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#33 Kwiatek

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Posted 17 October 2010 - 11:07

All the RL pilot accounts you mention and which you quoted in the past were always in regards to the Pfalz D.III.

If you have any pilot accounts on stall characteristics on the D.IIIa or the Albatros please share them. Little if any have come up so far that support your claims of them stalling easily, besides the D.III does stall and spin easily already if you handle it too roughly. The D.Va is a different matter though.

Pflaz DIIIa had the same wing profile (airfoil) like DIII. changes were only in wing tips. German pilot raported that both Pfalz DIII and Albatros had prone to stall characteristic but were quite easy to reocovery. ( Pflaz DIII was more hard to recover beacuse of smaller rudder area). Looking at these planes wing profiles ( airfoils) i dont have doubt why German pilots reported such. If you dont buy it i really think that develompent team should think about change some beta testers which could have influence in FM changes. Im no wonder why some ROF planes fly like now in ROF.
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#34 MiG-77

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Posted 17 October 2010 - 11:11

Mig you got wrong data for Camel and Nieuports.
Camel used RAF 14 profile which is very close to RAF 15 ( SE5a) but little more cambered. RAF 15 (Se5a) has 1.05- 1.1 Clmax at 15 deg angle of attack. So RAF 14 would be similar.


NACA:
Attached File  RAF14.jpg   138.91KB   432 downloads

Max lift coefficiency is 0,54 according to that at 14-15deg AoA. It is little odd that it is written as Lc and not CL tought.
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#35 MiG-77

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Posted 17 October 2010 - 11:25

Now looking more closely it seems that those NASA charts drag coeffiency and lift coefficiency is mixed (names in to those left values). You have to read lift coefficinecy from drag coefficiency and vise verse :)

So it should be ~1,09 CLmax at 14-15deg AoA for RAF14. Which btw is in those Camel tests also too high. Ill check N17 next.
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#36 MiG-77

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Posted 17 October 2010 - 11:35

~1,03 CL for 10deg AoA for Eiffel 53 airfoil.
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#37 Kwiatek

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Posted 17 October 2010 - 11:53

Now looking more closely it seems that those NASA charts drag coeffiency and lift coefficiency is mixed (names in to those left values). You have to read lift coefficinecy from drag coefficiency and vise verse :)

So it should be ~1,09 CLmax at 14-15deg AoA for RAF14. Which btw is in those Camel tests also too high. Ill check N17 next.

Exacly i found the same :)
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#38 Kwiatek

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Posted 17 October 2010 - 11:57

~1,03 CL for 10deg AoA for Eiffel 53 airfoil.

Dont Nieuports used Eiffel 14?
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#39 MiG-77

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Posted 17 October 2010 - 12:10

According to YavorD from aerodrome Eiffel 53 is closest for Nieuport 17, 21, and 23 variants. Naca mentions in Eiffel 14 airfoil chart "breguet".
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#40 Kwiatek

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Posted 17 October 2010 - 12:24

Yes but Eiffel 53 is not N17 wing profile. I think it would be hard to find such profile.

Look here:

http://www.theaerodr...7-airfoils.html" onclick="window.open(this.href);return false;">http://www.theaerodr...com/forum/aircr … foils.html

Some make comparison Eiffel 53 with N17 wing profile airfoil and they werent the same.

It would be hard to find accurate profile for N17.

What i find the closiest is "Rozendaal" - but i cant find data for it.
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