Dora roll rate and turning rate, true to real-life data?

[Crumpp]

Except they do not. Yo-Yo was clear in the turning thread that the P-51 out turns the FW190.

 

For starters, your assumption on ClMax is at odds with his:

 

"You do not take in account different CL especially at the speed the best turn ratio is. Mustang has better CL max at low M-numbers and much preferrable at medium."

 

What assumption on the mustangs cl max.

 

You are confusing arguments here.

 

Yo yo conclusion do agree with my conclusion. Both sets of performance charts say the exact same thing.

I deleted my reply because that is really obvious.

[Hummingbird]

Considering that at 192kg/m2, the F4U4 had a stall speed of 96mph IAS, with a 41kg/m2 higher wingloading what do you think the 190's stall speed in IAS will be? Considering that they both used the same airfoil?

 

Or we can alway use the F6F-5's wingloading of 184kg/m2 and stall speed of 96 MPH CAS, but that'll be 49kg/m2 higher wingloading.

 

The actual TAS stalling speeds of the F6F & F4U were both substantially lower than that of the P-51, and thus that of the Fw190 as well. Hence why they so effortlessly outmaneuvered the P-51 esp. in turns during comparative trials.

 

The F6F & F4U did suffer from some issues that lowered the lift below what you'd expect though, such as the F4U's gull wing shape and intakes at the wing root leading edge, whilst the F6F featured an almost too thick wing root. Some of these things were necessary structurally for a carrier based aircraft though. By comparison the 190 features a much cleaner and higher AR wing, which benefits its CLmax & L/D ratio.

 

As for the 190's stalling speed, my estimate is that the Fw190D features a stalling speed about the same as that of the P-51D at similar loads. They are much closer than most would expect, and its' something we'll see some commenting on once restored examples of these two birds get to fly together in the coming future, I'm sure.

[Hummingbird]

This is for only part of the foil.....not a wing. And therefore irrelevant. Go get a FW190 wing tunnel test of the entire wing etc and then you might actually have something.

 

:rolleyes: You missed the part that says wing characteristics (A.R. 6 , round tips) ;)

[GrapeJam]

The actual TAS stalling speeds of the F6F & F4U were both substantially lower than that of the P-51, and thus that of the Fw190 as well. Hence why they so effortlessly outmaneuvered the P-51 esp. in turns during comparative trials.

 

I found the margin in CAS to be very similar. And I'd not mind if you link me the TAS stall speed of all those American planes.

 

The F6F & F4U did suffer from some issues that lowered the lift below what you'd expect though, such as the F4U's gull wing shape and intakes at the wing root leading edge, whilst the F6F featured an almost too thick wing root. Some of these things were necessary structurally for a carrier based aircraft though. By comparison the 190 features a much cleaner and higher AR wing, which benefits its CLmax & L/D ratio.

 

As for the 190's stalling speed, my estimate is that the Fw190D features a stalling speed about the same as that of the P-51D at similar loads. They are much closer than most would expect, and its' something we'll see some commenting on once restored examples of these two birds get to fly together in the coming future, I'm sure.

Ok, let's take the F8F2, the F8F's airfoil(actually the 23018 has slightly and smoother better lift characteristic than the 23015) is almost exactly the same as the 190 and had very similar stall characteristic (as Grumman got "inspired" from a captured 190). The F8F2 at 10200lbs had a clean stall speed of 86 KIAS(99 mph), and a wingloading 204kg/m2. That is 15% lower wingloading than the D9, so I'm using my very simple math logic, that the stall speed at 233kg/m2 would be 15% higher, and thus place the stall speed somewhere around 113mph IAS.

 

Yes I'm fully expecting you to call out at the "IAS" thing.

Edited April 8, 2015 by GrapeJam

[Hummingbird]

I found the margin in CAS to be very similar. And I'd not mind if you link me the TAS stall speed of all those American planes.

 

Ok, let's take the F8F2, the F8F's airfoil is almost exactly the same as the 190 and had very similar stall characteristic (as Grumman got "inspired" from a captured 190). The F8F2 at 10200lbs had a clean stall speed of 86 KIAS(99 mph), and a wingloading 204kg/m2. That is 15% lower wingloading than the D9, so I'm using my very simple math logic, that the stall speed at 233kg/m2 would be 15% higher, and thus place the stall speed somewhere around 113mph IAS.

 

Yes I'm fully expecting you to call out at the "IAS" thing.

 

The F8F features leading edge radiator intakes at the wing root just like the F4U, which hurts its' lift coefficient. Next there's the lower AR of the F8Fs wing (5.2 vs 6.03), which again will lower the lift coefficient and L/D ratio.

[GrapeJam]

The F8F features leading edge radiator intakes at the wing root just like the F4U, which hurts its' lift coefficient. Next there's the lower AR of the F8Fs wing (5.2 vs 6.03), which again will lower the lift coefficient and L/D ratio.

http://airfoiltools.com/polar/details?polar=xf-naca23015-il-1000000

Edited: oh you meant the AR. But in anycase, nope, not seeing the D9's Clmax got above 1.55, the 23018 clmax's at 1.54 but much smoother.

 

Again, how much do you think the 190's wing lift is better than the F6F5? Give me a percentage.

 

But frankly the F8F's intakes are so small I don't think they factor in much. Also the F8F has wheel covering, the lack of wheel covering doesn't hurt the D9?

Edited April 8, 2015 by GrapeJam

[Yo-Yo]

No because I don't consider it accurate, hence my previous comment regarding these old 1940's test results and their accuracy. They are basically only accurate relative to each other if done side by side, otherwise they are misleading.

 

Now if only you would provide all these sources you keep talking about then it would makes things a lot easier.

 

What I got on both the NACA 23XXX series and NAA/NACA 45-100, NACA 65 & 66 series all yields an average difference in CLmax of .20 in favor of the NACA 23XXX at ALL speeds that these WW2 fighters were flying at. If you have data to contradict this then post it.

 

The realistic CLmax figures for the Fw190 & P-51 wing are ~1.60 and ~1.40 respectively. Every test at the relevant Reynolds number and speeds say the same thing, ESPECIALLY if field surface roughness is considered as the NACA 23XXX series suffers far less here - and let's face it, these birds weren't flying around with waxed & polished wings ;)

 

It starts to be a little bit boring...

First of all: you mix laboratory rectangular models with constant thickness with a real tapered wing with twist and (shout!) variable thickness along its span.

The second: you mix WING lift and AIRCRAFT lift that is not the same because a part of the wing is a fuselage that has no wing properties.

THe third: you mix WIND TUNNEL lift and TRIMMED lift that generally is lower because of trim losses.

 

So, please never tell people about 1.6 for 23XXX. In 1945 people already made some measurements for the fighter-type tapered wing

http://ntrs.nasa.gov/search.jsp?R=19930092809

 

AndI guess this one

http://ntrs.nasa.gov/search.jsp?R=19930084610

 

will stop all speculation about "poor laminar airfoil of P-51" showing the things I told many times before.

[NineLine]

Having a déjà-vu here...

 

In short, all this comes from different Cl values Hummingbird is arguing about. Hence Yo-Yo's last post.

 

 

 

 

Please read again what SiThSpAwN posted. Unless I am mistaken, this is a class act sarcasm. :)

 

:thumbup:

[GrapeJam]

I've just got an F51D's pilot manual. The take off speed at 10000lbs is 95-100mph IAS, the touch down speed is 90 mph IAS.

Also, the take of distance is 1100ft airborne, and 1850 to get to 50ft altitude.

 

 

 

 

The A8's pilot handbook list a landing speed of of 177km/h, and a take off distance of 650m concrete, at Dora's weight.

 

 

 

Edited April 8, 2015 by GrapeJam

[Hummingbird]

I've just got an F51D's pilot manual. The take off speed at 10000lbs is 95-100mph IAS, the touch down speed is 90 mph IAS.

Also, the take of distance is 1100ft airborne, and 1850 to get to 50ft altitude.

 

 

 

 

The A8's pilot handbook list a landing speed of of 177km/h, and a take off distance of 650m concrete, at Dora's weight.

 

 

 

That's the take off distance to clear a height 20m (66 ft) Grape, note the "S20".

 

As for the Landing speed, it's TAS and relates to the Anton with its' dirtier wing. Landing speed at full weight for the Dora would be ~170 km/h TAS.

 

Here are the actual take off distances:

 

Take off distance on concrete is 365 m for the Dora and 430 m for the A-8, and 570 meters for the Dora to clear 20 m height.

Edited April 9, 2015 by Hummingbird

[GrapeJam]

And by comparison the P51D took 1100ft(335 meters) to get airborne, at 10000lbs (with full fuselage tank), and no and the usual weight the P51D get into combat with is 9500lbs, so what do you think?

 

Also that landing speed figure was in the pilot's handbuch so it'd be strange if it was TAS, it didn't mention anything about where it's IAS or TAS.

Edited April 9, 2015 by GrapeJam

[Hummingbird]

It starts to be a little bit boring...

First of all: you mix laboratory rectangular models with constant thickness with a real tapered wing with twist and (shout!) variable thickness along its span.

The second: you mix WING lift and AIRCRAFT lift that is not the same because a part of the wing is a fuselage that has no wing properties.

THe third: you mix WIND TUNNEL lift and TRIMMED lift that generally is lower because of trim losses.

 

So, please never tell people about 1.6 for 23XXX. In 1945 people already made some measurements for the fighter-type tapered wing

http://ntrs.nasa.gov/search.jsp?R=19930092809

 

AndI guess this one

http://ntrs.nasa.gov/search.jsp?R=19930084610

 

will stop all speculation about "poor laminar airfoil of P-51" showing the things I told many times before.

 

Haha, I knew it! :D I had a feeling you had very selectively chosen said report and that you missed the part that said:

 

"The P-51B and the YP-80A airplanes had very carefully filled, waxed, and polished surfaces. The other airplanes were painted with standard camouflage paint.. Of the six airplanes tested, the P-38F and P-39N airplanes had the roughest finish and the most openings in the wings."

 

Once subjected to std. condition roughness the laminar flow NAA/NACA 45-100 airfoil dropped off drastically in CLmax, as evident in full scale tests, some of which I linked & referenced earlier.

 

In short, you need to revise your CL figures for the P-51, unless ofcourse you want us to fly around in one with carefully filled, waxed & polished wings vs aircraft with wings in rough operational field conditions :D

Edited April 9, 2015 by Hummingbird

[Hummingbird]

And by comparison the P51D took 1100ft(335 meters) to get airborne, at 10000lbs (with full fuselage tank), and no and the usual weight the P51D get into combat with is 9500lbs, so what do you think?

 

Also that landing speed figure was in the pilot's handbuch so it'd be strange if it was TAS, it didn't mention anything about where it's IAS or TAS.

 

Again you are misreading the manual, the P-51D took 1450 ft to take off at 9400 lbs, and 1730 ft at 10,100 lbs:

[GrapeJam]

That's tactical planning for commander, wouldn't it make sense for it to leave room for error in case of emergency?

 

My figurse are straight from pilot's handbook, I've even posted it here.

[Hummingbird]

That's tactical planning for commander, wouldn't it make sense for it to leave room for error in case of emergency?

 

My figurse are straight from pilot's handbook, I've even posted it here.

 

The manual refers to an emergency take off of absolute minimum distance at max power, the German & US chart I posted shows the normal distances.

 

For example the German pilots handbook also lists a min take off distance to clear 20m of 640 m vs the regular 715 m in the German planning chart similar to the American one I just posted.

 

By comparson the Dora-9 features a min take off distance of just over 310 meters.

Edited April 9, 2015 by Hummingbird

[GrapeJam]

The manual refers to an emergency take off of absolute minimum distance at max power, the German & US chart I posted shows the normal distances.

 

Oh really? I've read the whole manual and pretty sure that wasn't emergency take off. Anyway, as I've told you, this is the minimum take off distance for 10000lbs (most likely with wing racks as it's the common configuration), at 61"hg, P51D don't go into combat with fuselage tank full so the usual weight should be 500lbs less.

 

For example the German pilots handbook also lists a min take off distance to clear 20m of 640 m vs the regular 715 m in the German chart similar to the American one I just posted.

 

By comparson the Dora-9 features a min take off distance of roughly just over 310 meters.

Care to provide source? At what weight? Edited April 9, 2015 by GrapeJam

[NineLine]

Haha, I knew it! :D I had a feeling you had very selectively chosen said report and that you missed the part that said:

 

"The P-51B and the YP-80A airplanes had very carefully filled, waxed, and polished surfaces. The other airplanes were painted with standard camouflage paint.. Of the six airplanes tested, the P-38F and P-39N airplanes had the roughest finish and the most openings in the wings."

 

Once subjected to std. condition roughness the laminar flow NAA/NACA 45-100 airfoil dropped off drastically in CLmax, as evident in full scale tests, some of which I linked & referenced earlier.

 

In short, you need to revise your CL figures for the P-51, unless ofcourse you want us to fly around in one with carefully filled, waxed & polished wings vs aircraft with wings in rough operational field conditions :D

 

Try not to assume these are the only reports he might have used for his research. Seems you are trying too hard to prove people wrong... not sure why anymore at this point...

 

anyways, as a simple reminder:

 

Thread topic: Dora roll rate and turning rate, true to real-life data?

 

Just in case we all want to get back on topic.

[Hummingbird]

Oh really? I've read the whole manual and pretty sure that wasn't emergency take off.

 

It says it explicitly, and it's even illustrated by a P-51 JUST clearing a treeline just incase someone should mistranslate it as the regular take off distance.

 

Care to provide source? At what weight?

 

You have it right infront of you ?!? The POH lists distance at Start u. Notleistung (max take off power), the planning chart at Steig u. Kampfleistung (max continuous power), it says it very clearly and it can be seen on the climb rate figures too.

 

Hence: Take a look at the A-8's take off distance to clear 20m on the planning chart at Kampfl. as opposed to the min distance shown in the POH at Start u. Ntl = There's a difference in distance of a whopping 75 m (246 ft) !

 

Same will naturally apply to the Dora.

Edited April 9, 2015 by Hummingbird

[Hummingbird]

Try not to assume these are the only reports he might have used for his research. Seems you are trying too hard to prove people wrong... not sure why anymore at this point...

 

anyways, as a simple reminder:

 

Thread topic: Dora roll rate and turning rate, true to real-life data?

 

Just in case we all want to get back on topic.

 

Erm.. that's exactly what we're discussing? We're just simply using its direct competition ingame as a reference point, which is very much On Topic.

 

If Yo-Yo used the documents he just posted as reference, which he rather implies he has, then that would explain the discrepency ingame we see atm.

 

In real life, under std. roughness operational conditions, the regular non laminar airfoils, such as the NACA 23XXX, came into their own, experiencing no decrease in CLmax and sometimes even seeing an increase. It was the exact opposite for the laminar flow designs, as proven in the full scale tests conducted both then and more recently.

[GrapeJam]

It says it explicitly, and it's even illustrated by a P-51 JUST clearing a treeline just incase someone should mistranslate it as the regular take off distance.

 

Since when:

 

"It is recommended that 61" Hg and 3000 rpm

be used for all take offs and that this power

setting be reached as quickly as possible after

the take off run is started. Do not jam throttle

forward, as torque will cause loss of control of

airplane."

Is explicitly stated as emergency? Because of the tree? Pls.

 

 

You have it right infront of you ?!? The POH lists distance at Start u. Notleistung (max take off power), the planning chart at Steig u. Kampfleistung (max continuous power), it says it very clearly and it can be seen on the climb rate figures too.

 

Hence: Take a look at the A-8's take off distance to clear 20m on the planning chart at Kampfl. as opposed to the min distance shown in the POH at Start u. Ntl = There's a difference in distance of a whopping 75 m (246 ft) !

 

Same will naturally apply to the Dora.

So roughly the same as the P51D at 10,000lbs, 10,000lbs(and most likely with wings racks). See the problem?

 

Oh and mind you, the D9 has even at take off power has better powerloading than the P51D's at emergency power.

 

And at what speed does the Dora gets airborne? And at what speed does the Dora touch the ground?

Edited April 9, 2015 by GrapeJam

[NineLine]

Erm.. that's exactly what we're discussing? We're just simply using its direct competition ingame as a reference point, which is very much On Topic.

 

If Yo-Yo used the documents he just posted as reference, which he rather implies he has, then that would explain the discrepency ingame we see atm.

 

In real life, under std. roughness operational conditions, the regular non laminar airfoils, such as the NACA 23XXX, came into their own, experiencing no decrease in CLmax and sometimes even seeing an increase. It was the exact opposite for the laminar flow designs, as proven in the full scale tests conducted both then and more recently.

 

Are you saying you believe the Dora was built on testing by the US on US aircraft, because the topic is the Dora? This is why I try and stay out of these discussions because you guys are all over the board sometimes... as I said, working so hard to prove something wrong.

[Yo-Yo]

Haha, I knew it! :D I had a feeling you had very selectively chosen said report and that you missed the part that said:

 

"The P-51B and the YP-80A airplanes had very carefully filled, waxed, and polished surfaces. The other airplanes were painted with standard camouflage paint.. Of the six airplanes tested, the P-38F and P-39N airplanes had the roughest finish and the most openings in the wings."

 

Once subjected to std. condition roughness the laminar flow NAA/NACA 45-100 airfoil dropped off drastically in CLmax, as evident in full scale tests, some of which I linked & referenced earlier.

 

In short, you need to revise your CL figures for the P-51, unless ofcourse you want us to fly around in one with carefully filled, waxed & polished wings vs aircraft with wings in rough operational field conditions :D

 

Then please take a pilots notes for Mustang III and calculate max lift coeff using the data for corrected IAS. Then take a look at the second report for the ideal 230xx wing. Generally I do not see a reason to discuss to your scholastic arguments.

 

By the way, Miss Velma that was our test bench has no mirror-like polished wing. The stalls and g-s it can perform were compared to the FM regarding the actual gross-weight.

 

So, all speculation about well hammered and deeply scratched wing of the Mustang we have to model vs Dora will be only speculation. We model planes in mint condition because we can refer to the measured in various tests parameters.

Edited April 9, 2015 by Yo-Yo

[KenobiOrder]

Erm.. that's exactly what we're discussing? We're just simply using its direct competition ingame as a reference point, which is very much On Topic.

 

If Yo-Yo used the documents he just posted as reference, which he rather implies he has, then that would explain the discrepency ingame we see atm.

 

In real life, under std. roughness operational conditions, the regular non laminar airfoils, such as the NACA 23XXX, came into their own, experiencing no decrease in CLmax and sometimes even seeing an increase. It was the exact opposite for the laminar flow designs, as proven in the full scale tests conducted both then and more recently.

 

Im just going to point out again that there is precedent for Yo-Yo's FM in this regard. Pretty much every single issue that has been pointed out in this game and admitted later as a flaw (dora and 109 climb rates for example, damage modeling etc) had historical documentation to demonstrate that the game was wrong, or performance calculations from other sims or trained individuals to contradict it.

 

Your taking issue with the turn performance he has modeled for no other reason than you---and you alone---have some cockamamie numbers youve assigned to these planes that every other person in this thread has shown you to be wrong----in two separate threads now.

 

The Fw190D's performance in this game regarding turn is completely fine. It is perfectly consistent with its relative performance vs the P-51D in every other sim to date. Yo-Yo isnt doing anything different----funny how every other person to make FM's for these planes got the same basic turn performance. I guess they are all stupid and only Hummingbird knows the secrets of the FW-190D.

[[DBS]TH0R]

F4U-4 @ 12,401 lbs

Wing Loading = 39.4 lbs/sq.ft.

Stall speed (IAS), clean & power off = 96 mph (CAS = 102 mph)

 

P-51D @ 9,000 lbs

Wing Loading = 38.3 lb/sq.ft.

Stall speed (IAS), clean & power off = 101 mph (CAS = 107 mph)

 

Above would not be possible if it wasn't for the fact that the NACA 23XXX series airfoil provides a higher lift coefficient than the P-51's laminar flow airfoil, and this is despite a slightly higher wing loading and a gull wing design which without a doubt reduces the efficiency of the wing.

 

Just throwing this in: http://www.avialogs.com/index.php/en/aircraft/usa/northamericanaviation/p-51mustang/nzap-2025h-pn-pilots-notes-for-mustang-p51d.html

 

p. 34 ... Stalling speed, engine off:

 

Case "C" at normal load 9472 lbs

 

Undercarriage and flaps up: 86 knots I.A.S.

 

Undercarriage and flaps down: 78 knots I.A.S.

 

 

EDIT: "Canceled" section of the same paragraph is in mph, in favour of the kts. The only difference being 86 kts ~ 99 mph IAS.

Edited April 10, 2015 by T}{OR

[GrapeJam]

Hmn, the F51D in my manual got M3 HMG(which was heavier, and also had a recoil booster on the end of the barrel, giving the barrel a tapered look. It also extended the length of the gun by about an inch, so the barrels stuck out a bit further from the inboard and outboard locations in the wings) instead of the M2, I wonder if this caused the difference in stall speed.

 

The F51D also got strangely reduced fuel capacity but weighted strangely slightly more, it was also used primarily as a fighter bomber in Korea so I wonder if it got extra armor over the standard P51D.

Edited April 9, 2015 by GrapeJam