Dora vs Mustang: Turning

[Deckerd]

Hi,

this diagram has something strange to it. CL max L means lift. But in german it is CA. A is for the german word Auftrieb. i doubt it is of german source....

 

CL = coefficient of lift. As lift is a function of airspeed, air density etc... Looks german to me ;) Not an original WWII doc though.

I'm not sure though if split flaps are more effective in combat as conventional flaps. They add a lot additional drag for the increase in lift.

[Yo-Yo]

Right, as already stated the windtunnel tests of the day were quite unreliable in attaining accurate coefficients and different yet similar tests often yielded wildly different results.

 

That's why looking at stalling speeds, take off distances and landing speeds are helpful.

 

As an example the Bf-109G6 featured a clean (no flaps, gear up) stalling speed of ~140 km/h, the Spitfire IX one of 133 km/h, the FW190A8 one of 175 km/h and the P-51D one of 172 km/h (same as Dora-9).

 

What this proves is that the 190's wing had to have a higher CLmax in order for this to at all be possible, as its wing loading is higher.

 

That the FW190 featured a lower landing speed and shorter take off run than the P-51 can be explained by the more effective split flaps, which incidentally would also prove beneficial in a dogfight:

 

Where do you get 172 kph for the Mustang? Pilot's notes for Mustang-III, for example, gives 90 mph. Even if we keep in mind Pitot correction (by exrapolation of the given table values) up to plus 10 mph it gives 160 kph.

[Kurfürst]

I see you retain your winning personality by resorting to personal attacks when a simple denial would do Kurfurst. Anyway, excuse me if I got you confused with Hummingbird but since you have a history of posting under nics suspecting that you are one and the same is not such a stretch so spare me the indignation please.

 

You still seem to be confused. I only use this and this nickname only on all discussion boards, and of course for my site. In contrast, you run several nicknames like Pilum and Holtzauge and others, because they seem to get worn out rather quickly.

 

I doubt you are in a position to make blanket statements on documentation in DCS's inventory Kurfurst. However, given your hubris you probably refer to the documentation you have contributed. In that case I’m sure DCS by now have figured out that this constitutes the absolute top performance outliers on the Me109 and the rock bottom results for the Spitfire and other allied aircraft.

 

Oh, I see, you are trying to drag me into a fight. Sorry, not interested.

 

As for DCS, I believe they have all the relevant documentation already, including all the documents you have referred to. I have provided what assistance I could provide for them, just as I did when I am approached or asked to do so with other combat flight sims, researchers or magazines etc. I ask nothing in return and I do that as my spare time permits. It does not concern me if you get frustrated by that, and/or by the general disinterest in C++ based guesstimates.

 

I am also fully confident in DCS's ability to correctly interpret that documentation. In my opinion, they have a most impartial, professional team with utmost respect to historical accuracy and true dedication for very detailed modelling.

Edited September 10, 2014 by Kurfürst

[Pilum]

You have made three posts in this thread now Kurfurst: #127, in which you termed the British RAE measurements as guesswork, the Charles Meudon wind tunnel tests as useless and our efforts here as "guesswork countered by guesswork". You followed up with #170 which speaks for itself and now #178 above which is a continuation on the theme.

 

Just where in this muck is there an iota of constructive input? By your own admission you don't want a fight so why don't you do everyone here a big favour and just go away so we mere mortals can get on with our "guesswork"?

[Pilum]

Thanks to USStarkey I got some 75" boost Packard Merlin V-1650-7 data and have now run that in the C++ simulation: I was actually expecting the difference in turn rate to be larger but the P51 at 75" boost does now have both the smallest turn radius and also turn rate although maybe the difference is not as big as expected:

 

The shortest turn time for the P51 is now with 75" boost circa 21.2 s which is better than both the Anton and Dora. However, maybe it's not so strange that the difference is not larger than it is because while the P51 certainly has a lower wingloading, the Dora still has a 13% higher P/W ratio even with the Pony at 75" boost.

 

Also, looking at the figure it is seems that the top speed at 1 Km altitude is nearly identical if Pony has 75" boost since the turn rate curves for both aircraft above 555 Km/h are now superimposed.

 

The C++ speed simulation at 75" boost now gives the Pony a speed at sea level of 613.5 Km/h or 381 mph. At high altitude (6.2 Km or 20,340 ft) 732.1 Km/h or 455 mph. Think I've seen the 380 mph low alt figure somewhere before but I don't have any historical data on the high alt figure though.

P51D Fw190D9 stationary turn rate PAF PA49.bmp

Edited September 10, 2014 by Pilum

[Pilum]

I would like to see the translation as I am not sure I have the English version.

I have a report about roll rate and ailerons effectiveness but the images have very small size and not convenient to read.

 

Sorry, I don't have the stick force report in English translation. The one I have is in German and I got the English title from the microfilms first cover page.

 

On the Me109 roll rate report I may be able to help you: I have a copy with quite good images.

 

PM me which page/pages you need and I'll see what I can do.

[Hummingbird]

Where do you get 172 kph for the Mustang? Pilot's notes for Mustang-III, for example, gives 90 mph. Even if we keep in mind Pitot correction (by exrapolation of the given table values) up to plus 10 mph it gives 160 kph.

 

From the pilots handbook.

 

Here a stalling speed of 106 mph (172 kph) is listed at 10,000 lbs, and 101 mph (162 kph) at 9000 lbs.

 

If you're assuming a 90 mph stall speed for the P-51 (even the B or C) then you're being very optimistic, as not even at 8,000 lbs did it go below 94 mph (153 kph).

[Friedrich-4B]

From the pilots handbook.

 

Here a stalling speed of 106 mph (172 kph) is listed at 10,000 lbs, and 101 mph (162 kph) at 9000 lbs.

 

If you're assuming a 90 mph stall speed for the P-51 (even the B or C) then you're being very optimistic, as not even at 8,000 lbs did it go below 94 mph (153 kph).

 

Mustang III PNs:

 

 

stalling speed = 90 mph Flaps and Undercarriage up:

 

[Pilum]

Correction: Unfortunately, it turns out that the P51D best turn time estimate of 21.2 s and figure in post #180 was actually for 9600 lb not for 9300 lb as the figure says. I realized I had used my default setting of 9600 lb instead of the 9300 lb that should have been used in the comparison with the Dora for the reasons as outlined in post #154.

 

The shortest turn time for the P51D at 1Km altitude is now with the correct 9300 lb weight reduced to 20.6 s and the doghouse chart now looks more as expected with the P51D showing a substantial advantage in both turn rate and radius.

 

I think the figure is also interesting in a general sense since it graphically illustrates the point that any given plane can be made to turn faster by adding power, albeit at a higher speed.

[ZaltysZ]

Can you do a chart for 5000m? :)

[Pilum]

Can you do a chart for 5000m? :)

 

Yes, I could do that but why 5km in particular? :)

[Pilum]

Here you go!

[ZaltysZ]

Yes, I could do that but why 5km in particular? :)

 

8km is alt at which Pony shines, and 5km (or so) is where Dora should shine. This is assuming Dora vs Pony fighting each other, and taking into account their different altitude characteristics. It would be interesting to see a turn charts there too.

[Pilum]

8km is alt at which Pony shines, and 5km (or so) is where Dora should shine. This is assuming Dora vs Pony fighting each other, and taking into account their different altitude characteristics. It would be interesting to see a turn charts there too.

 

Yes, from the chart it looks like as long as the Dora stay's above 380 Km/h TAS at 5 Km altitude it turns better. Also, I have not done a speed comparison but from the turn chart it looks like the Dora is faster (very slightly that is!) even than the 75" Pony at this altitude :)

[[DBS]TH0R]

From the pilots handbook.

 

Here a stalling speed of 106 mph (172 kph) is listed at 10,000 lbs, and 101 mph (162 kph) at 9000 lbs.

 

If you're assuming a 90 mph stall speed for the P-51 (even the B or C) then you're being very optimistic, as not even at 8,000 lbs did it go below 94 mph (153 kph).

 

This video tutorial states around 95 MPH IAS with flaps and gear up for B variant:

 

[Hummingbird]

This video tutorial states around 95 MPH IAS with flaps and gear up for B variant:

 

 

Yeah, with the engine on.

 

Engine off the stall is at 106 mph at 10,000 lb, whilst even at 8,000 lbs the stalling speed doesn't drop below 94 mph.

 

[bongodriver]

Getting a bit 'clutch at straws', who on earth is going to try and get max turn performance with power at idle, bombs and tanks attached?

 

lets see the list of stall speeds for the 190 with all those configurations and compare it then.

[Kurfürst]

Getting a bit 'clutch at straws', who on earth is going to try and get max turn performance with power at idle, bombs and tanks attached?

 

No-one, of course, but its worth noting that the 1.4ish cl figures for the 109E thrown around by some refer to the exact same condition - power at idle.

 

Pretty pointless excercise IMO, as CLmax figures vary with g-load etc. as well, so a CLmax figure referring to "dirty" landing (ie. flaps /gears down, power off, 1g) flight regime won't get you an inch closer to estimate turn rate at multiple g-s, power max etc, ie the flight regime of turning... ;)

[Hummingbird]

Getting a bit 'clutch at straws', who on earth is going to try and get max turn performance with power at idle, bombs and tanks attached?

 

lets see the list of stall speeds for the 190 with all those configurations and compare it then.

 

The figures for the 190 are with engine off as well.

 

The figures in the first collumn are without bombs and tanks attached as well, with only the racks as every P-51D came equipped with for escort.

[Lizzard]

After playing around with the Dora quite a while I still have a very hard time Dogfighting the Mustang...o.k. maybe I am just a shitty Dogfighter, but it seems the Mustang outturns and outclimbs me easily..even with engaged supercharger?! It also needs a LOT of Hits to shoot the P-51 down..this Bird really can take damage..

For fun I created an AI Furball..8 FW-190 vs 8 P-51...all set to exellent....everytime I watch this it goes 8:0 for the P-51..so all Doras shot down..the P-51s nearly no scratches...

 

Was the P-51D really so far superior?!

[Chlebakus]

After playing around with the Dora quite a while I still have a very hard time Dogfighting the Mustang...o.k. maybe I am just a shitty Dogfighter, but it seems the Mustang outturns and outclimbs me easily..even with engaged supercharger?! It also needs a LOT of Hits to shoot the P-51 down..this Bird really can take damage..

For fun I created an AI Furball..8 FW-190 vs 8 P-51...all set to exellent....everytime I watch this it goes 8:0 for the P-51..so all Doras shot down..the P-51s nearly no scratches...

 

Was the P-51D really so far superior?!

 

Mustang AI is quite beatable one. I recommend you to try dogfights vs the easiest skill level AI. I fly Dora a lot these days with my new rudder pedals and I am surprised, how good she is in turns. Maybe try another tactic. Don't try to outturn Mustang too much. If you keep some energy and use combat climbing turns, he won't be able to reach you and you eventually loop behind him. As you are on his six, he will have very hard time to run away. When you end in chasing each other in circle, you should win this with full throttle as he is generally slower than you. Forcing your enemy into vertical fight is also a good idea. Mustang is about 500 Kg to a ton heavier. He just can't escape you.

 

I 100% agree with AI indestructibility. I often have hard time to shoot AI Mustang down. After some 40 minutes long fight he turns into smoking wreck with holes everywhere, often withstand more than 40 hits from Dora's powerfull weapons and still continue to fight. Let's hope this will be improved in future. Maybe it's more like it MUST be improved as there is complete WW2 series incoming.

[Hummingbird]

After playing around with the Dora quite a while I still have a very hard time Dogfighting the Mustang...o.k. maybe I am just a shitty Dogfighter, but it seems the Mustang outturns and outclimbs me easily..even with engaged supercharger?! It also needs a LOT of Hits to shoot the P-51 down..this Bird really can take damage..

For fun I created an AI Furball..8 FW-190 vs 8 P-51...all set to exellent....everytime I watch this it goes 8:0 for the P-51..so all Doras shot down..the P-51s nearly no scratches...

 

Was the P-51D really so far superior?!

 

Short answer is: No it wasn't, and there's obviously an accuracy issue with what lift coefficient figures the game is using.

 

The NACA 23XXX series airfoil has always featured a higher CL_max than the NACA 6 series, esp. considering a wing surface in operational condition.

 

Sad to say it, but I believe there is a fair bit of bias in the P-51's favour on this one.

[Lizzard]

Mustang AI is quite beatable one. I recommend you to try dogfights vs the easiest skill level AI. I fly Dora a lot these days with my new rudder pedals and I am surprised, how good she is in turns. Maybe try another tactic. Don't try to outturn Mustang too much. If you keep some energy and use combat climbing turns, he won't be able to reach you and you eventually loop behind him. As you are on his six, he will have very hard time to run away. When you end in chasing each other in circle, you should win this with full throttle as he is generally slower than you. Forcing your enemy into vertical fight is also a good idea. Mustang is about 500 Kg to a ton heavier. He just can't escape you.

 

I 100% agree with AI indestructibility. I often have hard time to shoot AI Mustang down. After some 40 minutes long fight he turns into smoking wreck with holes everywhere, often withstand more than 40 hits from Dora's powerfull weapons and still continue to fight. Let's hope this will be improved in future. Maybe it's more like it MUST be improved as there is complete WW2 series incoming.

 

 

I mostly not try to outturn the Mustang..I rely more on that energy fighting thing and try to climb away and dive back down (The Jojo thing:))...but the Mustang just climbs like crazy..I stall the Dory way before I am in a good shooting position...But I guess my whole energy management is jut not good enough:music_whistling: Anyway thanks for the reply..I`ll keep practising:joystick::thumbup:

[Lizzard]

Short answer is: No it wasn't, and there's obviously an accuracy issue with what lift coefficient figures the game is using.

 

The NACA 23XXX series airfoil has always featured a higher CL_max than the NACA 6 series, esp. considering a wing surface in operational condition.

 

Sad to say it, but I believe there is a fair bit of bias in the P-51's favour on this one.

 

uhm Thank you!..But I did not understand a single word...a bit too technical for my brain:D...but I guess it means..the performance data of the P-51 is not that realistic?!:):huh:

[[DBS]TH0R]

Short answer is: No it wasn't, and there's obviously an accuracy issue with what lift coefficient figures the game is using.

 

The NACA 23XXX series airfoil has always featured a higher CL_max than the NACA 6 series, esp. considering a wing surface in operational condition.

 

Sad to say it, but I believe there is a fair bit of bias in the P-51's favour on this one.

 

AI planes fly with perfect trim and all other benefits so there is no comparison to be had with player controlled versions.

 

On another note, that the P-51 has been favored / biased here is your opinion. One you weren't able to back up with sufficient evidence. Please continue.