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Europa

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Let me tell you why I think it is very important. The forces applied in the real plane translate to different control surface forces when the transmission = leverage and effector hinge moments change. That means for a fixed size elevator I can apply 300N of force on my stick and this may result in a hinge moment that is sufficient to deflect the elevator fully up to M = 0.3. But now I change the transmission and all of the sudden I can reach the same deflection with 300N of stick force easily at M= 0.6. Do you realize the relevance now? The reduced maximum elevator deflection in G-10/U4 and K-4 models was initially a clear indicator that transmission leverage have increased in these aircraft. And what I have calculated so far from blueprints is that there is a quite significant change in hinge moments. (https://www.ebay.de/itm/WW2-German-Flugzeug-Bauplan-Blueprints-Me109-Fw190/391441687123?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649)
You're very welcome to buy those charts and enlighten us all about the subject :thumbup: .

 

 

 

If you really think there should be any control reversal then I suggest you take out the DCS K-4 dive it to Mach 0.8 and check if your controls reverse. If it doesnt it must be modeled incorrectly and you should tell YoYo, right?

 

Im glad you dont insist on this. :)

You kidding, right? DCS module features the 1.15º trim fix in order to prevent the controls reversal. We'd have to have 2º to achieve that. It would be funny having 2º trim and see people smashing into ground saying trim doesn't work… :lol::lol::lol:

 

 

S!

"I went into the British Army believing that if you want peace you must prepare for war. I believe now that if you prepare for war, you get war."

-- Major-General Frederick B. Maurice

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So you guys say this is very normal.
If you don't trim that would happen in any aircraft in the World.

 

 

S!

"I went into the British Army believing that if you want peace you must prepare for war. I believe now that if you prepare for war, you get war."

-- Major-General Frederick B. Maurice

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You are kidding right? Still?

 

So you say it is quite normal that a Bf109 can hover and stall like a parachute. And you believe any untrimmed airplane will do the same thing? You can confidently say it as you read the papers and look at some charts. Please show me an airplane in the world where it can still tries to pitch up at stall speed and do not stall. LOL.

 

Seriously. What are you smoking guys I want that same thing. Lets get high together.

 

Why do I feel like Galileo against the Christian church.

 

"Nonetheless it moves"

 

It is no surprise yet there are still people in the world who will defend the world is flat no matter what.


Edited by Europa
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You are kidding right? Still?

 

So you say it is quite normal that a Bf109 can hover and stall like a parachute. And you believe any untrimmed airplane will do the same thing? You can confidently say it as you read the papers and look at some charts. Please show me an airplane in the world where it can still tries to pitch up at stall speed and do not stall. LOL.

 

Seriously. What are you smoking guys I want that same thing. Lets get high together.

 

Why do I feel like Galileo against the Christian church.

 

"Nonetheless it moves"

That's because they don't understand aerodynamics and how it works..

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Why do I feel like Galileo against the Christian church.

 

"Nonetheless it moves"

 

Haha, I loved that comment :D

 

I do find it strange...but I'm not saying it has to be wrong. I can do the same with a couple of training glider planes, we call it "the downward elevator"...also, I noticed you were flying at close to Vmin, but not below. What is unusual is that your stick was centered and the trim set to zero. There may be a good explanation, though. People like Yo-Yo know much more about these things.

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Haha, I loved that comment :D

 

I do find it strange...but I'm not saying it has to be wrong. I can do the same with a couple of training glider planes, we call it "the downward elevator"...also, I noticed you were flying at close to Vmin, but not below. What is unusual is that your stick was centered and the trim set to zero. There may be a good explanation, though. People like Yo-Yo know much more about these things.

 

People believe that there are no aileron or rudder trims in the Bf109 but that is not correct. In fact there are. It is pre-trimmed by the ground crew. Thanks to DCS it is also simulated and it is in the settings menu where you select special setting for the K-4.

 

I trimmed it to be -25 aileron and -25 rudder, So thats why the stick is in centered position and rudder is a little bit left to achieve the coordinated flight.

 

Also please re-check the video from 02:00 and look at the RPM. I hold the aircraft pitch up to achieve the stall speed and wait for the RPM to lower automatic. Minimum torque and idle thrust. You will see the airframe starts to shake signaling a stall. At that point I let go the stick and rudder. Throttle is idle and RPM is minimum. The airplane is not in landing configuration and flaps are fully retracted. The trim is constant at 0 at all times. You can achieve the same result.

 

Surprisingly I also tested with the engine out. I cut the engine and the result did not changed. I have the video and will post it.

 

Please note that the pitch up attitude is constant at all speeds, thrust and torque settings.


Edited by Europa
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Speaking of Vmin. Approach speed of the K4 is documented in the manual to be as 220 km/h which makes Vso 170 km/h (Vso: stall speed in landing configuration=1.3xVref (Vref: approach speed)). You can easily see that I am gliding at 170km/h (not in landing configuration) and that is below gliding speed which is documented to be 200 km/h. No wind. The power off gliding speed is 220-230 km/h (See the manual).

 

In the footage you can easily see that it is a little pitched up. Considering the drag added with the AoA it is surprisingly conservative holding the speed constant at 170km/h and very stable. Do the math this thing had to fall like a brick at that speed.

 

Who claims that this is perfectly normal as I did not trim the elevator and left it at 0, please step forward


Edited by Europa
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109 is in a Stall when you fly like his in a Video, Stall not means the Plane have to violate drop a Wing, when you push a little bit more on of the Wings start dropping slightly..

The 109 is clearly dropping down like a stone out of the Sky when you push it like in this Video because the most of the Airstream detached from the Profile WIng, only the slats bring enough Airflow over the Wing to keep in more or less stable in the Air..

In the Spitfire when you read the Reports, was still turning and flying in a accelerated Stall conditions because the Wing Loading was so low...

Once you have tasted Flight, you will forever walk the Earth with your Eyes turned Skyward.

 

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set prop to 11:20-11:30

2-2.5 notches flaps

full right (if i remember the direction right) rudder

and see the plane fly 170kph in big sidesplip.

do this close to ground and you'll see that it doesn't fall at all. just flies tight circle at <170kph with the tail sliding like in a rally car.

 

edit. i dont involve my self into discussions how it should be.

IT IS, and i just fly LIKE IT

 

edit 2 i usually fool around with the plane before landig so it's very light. so take little fuel to try it


Edited by voodooman
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rigolos

 

Always so funny with the DCS players:) we should never have told them that this game is close to the real.

This may be true in some situations investigated by programmers, close to the normal use of an aircraft, do not does not necessarily mean that you can use the game as a flight test thing. There are for sure flying areas, of the real plane, which have been left out. It is easy to find bugs and other anomalies in any game, but that does not justify useless and amalgamated discussions, where the legends, the flight mechanics datas and their associated aerodynamic calculations intersect, and the rumors peddled by the players who have no knowledge of the trade aeronautics and surfing the web.

Questioning the center of gravity that was chosen for the module of 109, or another module, is useless when we know that these parameters are only code far from the aerodynamic laws and only make it look like , simulate, imitate .... the real.

 

Finally we can actually fly to infinity (up to fuel 0, in fact) close to the stall speed without going below, with any light aircraft in real. And the 109 has "slats" in addition Like the Morane Saulnier Rally

which was practically impossible unhooked, we had to settle for a slow descent.

 

The high-winged planes do that very well too.

 

In DCS the 109 takes off very well with the trim in the neutral and a bit of trim forward after take off on the uphill slope the gear and flaps retracted, without problem.


Edited by cromhunt
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You're very welcome to buy those charts and enlighten us all about the subject :thumbup: .

I encourage you to reread my post. I have bought these and I have calculated hinge moments and I have said so in my post.

 

 

You kidding, right? DCS module features the 1.15º trim fix in order to prevent the controls reversal. We'd have to have 2º to achieve that. It would be funny having 2º trim and see people smashing into ground saying trim doesn't work… :lol::lol::lol:

 

 

S!

 

You are probably kidding me, right? Let me qoute Yo-Yo on this:

 

Yes, and 1.83 degree (1 deg and 50') we have now is a little bit more...
(https://forums.eagle.ru/showpost.php?p=2258251&postcount=36)

 

So the DCS module has the trim limited to 1.83 degrees as Yo-Yo said and that also can be tested youself within like one minute. Where in the world do you get that 2 deg number from? The 109 elevator mach tests show absolutely no control reversal... ever, at all, anywhere. You still are misunderstanding that one graph, arent you?

 

But by now I am honestly inclined to think you are trolling us because so far everything is pretty much the opposite of what you claim it is. I think I better rest my case here... :huh:


Edited by rel4y

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You are kidding right? Still?

 

So you say it is quite normal that a Bf109 can hover and stall like a parachute. And you believe any untrimmed airplane will do the same thing? You can confidently say it as you read the papers and look at some charts. Please show me an airplane in the world where it can still tries to pitch up at stall speed and do not stall. LOL.

 

Seriously. What are you smoking guys I want that same thing. Lets get high together.

 

Why do I feel like Galileo against the Christian church.

 

"Nonetheless it moves"

 

It is no surprise yet there are still people in the world who will defend the world is flat no matter what.

I said Galileo stuff first, don't try to copy me :D. Mate, have you tried that same in the trimmed aircraft? Have you tried that in a different but equally untrimmed aircraft? Have a go and come backo with the video. The slats shit you like so much about the 109 has some funny effects, yes. I don't exactly see what's your problem, it doesn't stall? Well I see it pretty much stalled in your video.

 

 

S!

"I went into the British Army believing that if you want peace you must prepare for war. I believe now that if you prepare for war, you get war."

-- Major-General Frederick B. Maurice

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That's because they don't understand aerodynamics and how it works..
No, they gave me away the pilot license in a biscuit packet… :megalol::megalol::megalol::megalol: You all aeronautical engineers and Chuck Yeagers are so fun to talk with.

 

 

S!

"I went into the British Army believing that if you want peace you must prepare for war. I believe now that if you prepare for war, you get war."

-- Major-General Frederick B. Maurice

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People believe that there are no aileron or rudder trims in the Bf109 but that is not correct. In fact there are. It is pre-trimmed by the ground crew. Thanks to DCS it is also simulated and it is in the settings menu where you select special setting for the K-4.

 

I trimmed it to be -25 aileron and -25 rudder, So thats why the stick is in centered position and rudder is a little bit left to achieve the coordinated flight.

 

Also please re-check the video from 02:00 and look at the RPM. I hold the aircraft pitch up to achieve the stall speed and wait for the RPM to lower automatic. Minimum torque and idle thrust. You will see the airframe starts to shake signaling a stall. At that point I let go the stick and rudder. Throttle is idle and RPM is minimum. The airplane is not in landing configuration and flaps are fully retracted. The trim is constant at 0 at all times. You can achieve the same result.

 

Surprisingly I also tested with the engine out. I cut the engine and the result did not changed. I have the video and will post it.

 

Please note that the pitch up attitude is constant at all speeds, thrust and torque settings.

:music_whistling::music_whistling::music_whistling::music_whistling: Why, oh, why so all of a sudden you remember me of somebody I know speaking the very same sh#$ of the 109 like the mad Luftwhiner he is…? Now would you ask for the 109 to fly hands off with 0 trim setting?? :music_whistling::music_whistling::music_whistling: Weird… :lol:

 

Please note that the pitch up attitude is constant at all speeds, thrust and torque settings.
No, that's not true, easily seen in any flight but you're there in a very controlled situation and settings.

 

 

Speaking of Vmin. Approach speed of the K4 is documented in the manual to be as 220 km/h which makes Vso 170 km/h (Vso: stall speed in landing configuration=1.3xVref (Vref: approach speed)). You can easily see that I am gliding at 170km/h (not in landing configuration) and that is below gliding speed which is documented to be 200 km/h. No wind. The power off gliding speed is 220-230 km/h (See the manual).

 

In the footage you can easily see that it is a little pitched up. Considering the drag added with the AoA it is surprisingly conservative holding the speed constant at 170km/h and very stable. Do the math this thing had to fall like a brick at that speed.

 

Who claims that this is perfectly normal as I did not trim the elevator and left it at 0, please step forward

:music_whistling::music_whistling::music_whistling: Again the guy asking for advice in what aircraft to buy now is an expert in the 109 and it's features… :music_whistling::music_whistling::music_whistling: No mate, you're using modern standards, but 170 is definitely not the Vs, let alone Vso for the 109. The aircraft is indeed falling like a brick as you say, but slats prevents it from doing anything else than gliding. It's funny, it definitely is, but who says that doesn't happens when there are known cases of aircraft landing on it's own after pilot bailed out.

 

 

I encourage you to reread my post. I have bought these and I have calculated hinge moments and I have said so in my post.

 

You are probably kidding me, right? Let me qoute Yo-Yo on this:

 

(https://forums.eagle.ru/showpost.php?p=2258251&postcount=36)

 

So the DCS module has the trim limited to 1.83 degrees as Yo-Yo said and that also can be tested youself within like one minute. Where in the world do you get that 2 deg number from? The 109 elevator mach tests show absolutely no control reversal... ever, at all, anywhere. You still are misunderstanding that one graph, arent you?

 

But by now I am honestly inclined to think you are trolling us because so far everything is pretty much the opposite of what you claim it is. I think I better rest my case here... huh.gif

Yeah, yeah, right, definitely we speak different things here :doh: . Bye.

 

 

S!

"I went into the British Army believing that if you want peace you must prepare for war. I believe now that if you prepare for war, you get war."

-- Major-General Frederick B. Maurice

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Again the guy asking for advice in what aircraft to buy now is an expert in the 109 and it's features…

 

 

S!

 

Even I say white you will say black. There is no point arguing or discussing things with people like you. Just another status quo.

 

You are making fun of me but make fun of your self. As I asked that to find peoples opinion to choose from 3 of the DCS models before I buy so I can buy something unbroken. I never asked type rating for Bf109. Can you understand the difference. You can not come to a conclusion that I know nothing about Bf109. Can you understand that?

 

..and what made you an Bf109 authority at first place?

 

 

This is a simulator. Do you know what is a simulator?

All you can do is to say "as real as it gets" You will never mimic the real thing %100 in a simulator. And if this is a rare ww2 bird than it is always questionable. None of you have ever flown it. Did you? Are you a test pilot of Bf109's or were you the assistant to Mr. Willy?

 

You can implement the performance of the airplane as much as the sim's game engine allows but the handling of it will be always different as even the joystick we are using will make difference.

 

There are other simulators out there (Surprise DCS is not the only simulator in the world) focused on WW2 era, lots of Bf109's and MS FSX/Prepar3D/Xplane where you can buy Bf109 AddOns. And I have them all, every Bf109 modeled out there. So I can easily talk about the "PERFORMANCE", "LOOK AND FEEL" and "HANDLING" differences between them. For example some of the models in DCS is the exact copy with the one in MSFSX. But the feeling is diffrent because the environment (the sim) is different.

 

Even you copy cat the performance numbers by the book in to the simulator. The core of the simulator will handle it different form sim to sim. It will feel different. Even the performance could be different as how good is the physics simulated in the sim. Always questionable. Laminar flow, fluid mechanics are really though subjects.

 

An airplane which is about to stall will naturally try to drop the nose to gain speed or otherwise fall like a brick. It will not sail like the one in the footage. In real world in all other simulators that is what happens.


Edited by Europa
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Well, just my 2 cents....

 

I have no authority to speak as an expert in the 109, but rather, 38 years flying gliders...

 

I have experienced many different sorts of stall behaviour along the years, depending on glider model. The "mushing stall" ones are the trickier. One of that kind is the Grob Jean / Standard.

 

In the Jeans, as in other gliders I've flown, the only signal you have of a stall is the slugginess of the controls, and of course the indications in the variometers...

 

Other than that, and provided you're at safe altitude, you can continue maneuvering the glider well within it's "stalled regime".

 

Other models like the AS-K21 so much used in training are so difficult to get into a spin that students think they're unspinable :-)

 

Other, like the Mucha, are so tricky that you really must be careful in your circuits, because it'll go into spin and kill you in a minute if you forget to properly make your base leg turn...

 

@Europa: So, your videos remind me a lot of some of these gliders and my RL experience flying them.

 

Not saying I feel the 109 k-4 is a perfection, if not for other reason because - how could I tell anyway ?

 

And BTW, I believe we all know about the ground adjustable trim tabs on the 109 K-4, introduced sometime ago in one of the v1 patches, but we also know about the ground adjustable elevator trim tab, present in the real 109s, but not in the DCS one...


Edited by jcomm

Flight Simulation is the Virtual Materialization of a Dream...

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Sorry to have to like "Jcomm" add my grain of salt to contradict you "europa" The problem is that you generalize too much the behavior of the aircraft.

Each aerodyne has a different behavior because it has a different architecture. A low-wing plane and a high wing plane do not drop in the same way. A glider compares to a motor plane, does not behave at all the same. .

Some also have slats and others do not.

Ask yourself why the 109 in question has slats and what they can serve?

http://www.boldmethod.com/learn-to-fly/aircraft-systems/leading-edge-slat-lift-device/

On this link you will find explanations on the use of "slats" on some and perhaps an answer to your questioning.

 

Do not believe, either, that a plane falls like a brick after a stall, it would be much too simple.Nor it naturally drops his nose.

It seems to me that you remain too focused on the center of gravity which is the object of your first post. While in aeronautics one prefers to refer to the center of thrust, which can move according to the incidence. Far from me plan to do a course you will find easily on the net of the subject.

And you're right in saying that DCS is just a simulation, and in a simulation, everything can not be reproduced with absolute accuracy compared to real, our computers can not yet offer us this possibility


Edited by cromhunt
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Just an excerpt from the mechanics of the flight.

The center of thrust (CP) is the point of application of the resultant forces of

pressure / depression generated by the intrados and extrados of the wing.

For an asymmetrical profile with positive curvature, the center of thrust advances towards the edge

of attack when the incidence of the wing increases. Conversely, it moves to the trailing edge

when the incidence decreases.

For a symmetrical profile, the position of the center of thrust is fixed whatever the incidence. CP

is located at a distance equal to approximately ¼ of the length of the profile cord.

 

do you think that our computers are capable of reproducing this kind of configurations?

I doubt it a little


Edited by cromhunt
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No, I speak well of the center of thrust, or center of applications of the aerodynamic forces.:)

I try to make it clear that the center of thrust is preponderant on the center of gravity, and since it can move relative to the center of gravity as a function of the aerodynamic results, it can create biting or hunching moments that modify the reaction of the plane.

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Judging from your description, I'd agree with Jcomm. In aerodynamics-related literature / manuals written in English, it's rather referred to as center of pressure (hence the universal abbreviation CP) - your post is the first time I see it being called "center of thrust" :D.

 

The most important thing is we know what you mean, though.

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Call it what you want:)

The main thing is that it indicates the point or center of applications of the aerodynamic forces.

And to avoid confusion of sorts, I'll stop there, no need to be on the head of a pin.


Edited by cromhunt
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if a plane makes you feel that "this is not how it should be! :(" you have way too much emotional investment in this hobby. you are dissappointed because YOUR personal favorite doesn't fly like you would like it to fly.

 

if however that module on the opposing side is enjoyably easy for YOU to kill, would it matter if it's not that realistic? would it matter to you if people favoring THAT plane cry about it here?

 

it's the emotional investment that you have developed to certain aircraft, wheter it comes from other sims, movies, books or whatever, that makes you disappointed that your favorite doesnt fly like it "should".

 

this, in my opinion, is clearly noticeable in EVERY FREAKIN realism debate.

 

when drop that emotional detachment, you'll notice that THIS sim is incredible collection of really well detailed aircraft, that will give you hours after hours of fun and excitement.

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You guys are biased. You keep saying the same thing. You dont even think about it. You don't even question the possibility of a problem. You belive the DCS model is the real thing and can't be questioned. You are obbsessed with the idea that everything is perfect and who questions this can only be "well yes he was looking for an imaginary Bf109 and he found a kick ass hard core sim so he must be fool not to see this".

 

The problem is not about what I expected and what I found or about I am whining because I can't fly it. Thats is your bias. In fact I can perfectly fly it.

 

Keep on what you belive and continue to warship.

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