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I will get you Bill.......................HAHAHAHAHAHAHAHAHAHA (evil laugh again if your wondering)
Stick to the topic guys, please, the argument between me and Bill will be solved soon enough.
Hello Crumpp,
I (Or we) need your knowledge on something, you see recently I got into an argument with a member at another forum for saying this:
The Fw-190's wing achieved elliptical lift distribution during G's because of aeroelasticity negating the original 2 degree twist applied to the 190's wing. This is what caused the violent departure in turns when pulling G's as compared to when stalling at 1 G.
This I learned from reading your posts as-well as Lednicer's article, however now I am being told I have misunderstood you Lednicer by Bill, who you seem to know already. Bill says :
"the Fw 190 and the Spitfire and the Mustang all start with somewhat of an elliptical lift distribution BEFORE the turn and have an 'elliptical like' (more for Spit/less for Fw 190 and Mustang) lift distribution in the turn"
I disagree with what Bill says.
Could you explain the matter for us all (On the WW2 a/c forum) in detail in a PM to me here, then I will forward it to the forum. (Or you could put it on your blog here so everybody can see it right away)
The thread is named Spitfire XIV vs Bf-109 K-4 vs La-7 vs Yak-3. And plz ignor Bill I's mud throwing, it has gotten completely out of hand..
Soren said:The Fw-190's wing achieved elliptical lift distribution during G's because of aeroelasticity negating the original 2 degree twist applied to the 190's wing. This is what caused the violent departure in turns when pulling G's as compared to when stalling at 1 G.
Bill said:"the Fw 190 and the Spitfire and the Mustang all start with somewhat of an elliptical lift distribution BEFORE the turn and have an 'elliptical like' (more for Spit/less for Fw 190 and Mustang) lift distribution in the turn"
Soren said:I see, so I was wrong when I said that Fw-190's wing achieved basically fully elliptical lift distribution in turns ?
Soren said:It was my understanding that the Spitfire's wing didn't achieve fully elliptical lift distribution because of the washout applied to the wing all the way out to the tips.
Ok got message from Gene (Crumpp) and here's what he had to say (I left my questions to him first);
My mail to Gene (Crumpp):
Gene's response:
Hi Soren,
I hope things are going well for you. I appreciate your vote of confidence.
I do know Bill. He is not only very knowledgeable but someone I consider a friend. It is very disappointing to hear that you two cannot get along discussing old airplanes.
I can certainly clarify what I meant however the two points do not seem to be related or at least I cannot see how they are related. The only thing in common is the term "elliptical lift distribution". Lednicer is referring to the cl/CL ratio which gives us a clue as to the wing efficiency. The analysis is made at 360Kts at 15,000 feet and is good for that condition. Wing efficiency will change with condition of flight and square wingtips can very easily be designed that equal elliptical wings. However they are designed to be that optimal for a specific condition of flight. For example at the Prmin point, L/Dmax, or Va would serve as a design point depending on what the performance the designer desired.
Since the Mustang and FW190 are designed to most efficient at one design point and the Spitfire has an elliptical wing which is efficient at all points, Lednicer's observation is correct in that the Spitfire probably has the most optimal of the three. Probably is used because the aerodynamic twist in the Spitfire wings in order to prevent the wing from stalling all at once reduces this efficiency. That too would be designed for an optimal point of performance.
Make Sense?
This statement refers to the fact aeroelasticity removes the aerodynamic twist placing the airfoil sections at the same co-efficient of lift. The sections then reach CLmax all at the same time. When one side of our wing or the tips stall, the aircraft will drop a wing or if the stall is large enough, the aircraft will roll inverted. That is what Lednicer is saying. This was not a design feature. It is just an explanation for the differences in the FW190's stall behaviors.
That is pretty much what the spanwise lift loading notes. It has nothing to do with the stall behaviors of the FW190 but is gaining insight as to the relative efficiency of the wing designs..
Does that help?
All the best,
Crumpp
I then sent him another mail, just incase I might have misunderstood anything he said, and here's his answer (With my questions):
No you are right. That is what causes the harsh stall. It is not a design feature however. It is just and explanation for the two different stall characteristics of the design.
You are right on this too. The Spitfire does not achieve the full efficiency benefits of elliptical wing construction due to the washout. At the same time though it is probably the most efficient of the three. If we examine the aircraft at a design optimum point, you will find little to no difference.
So the debate is now settled I hope.
My Mamma also told me that I was right. But the Mamma of the other boy told her boy that he was right. Anyway my Mamma told me that I was still right, and I told this the other boy, who then told me that his Mamma told him that I was not right but he was, which in turn was disputed by me after My Mamma reconfirmed me that not the other boy whose Mamma told him that he was right actually was wrong, however the Mamma of the other boy disagreed with my Mammas opinion about me and not her boy being right……..
Okay so if anybody on this forum wants to know who actually was correct please let me know in order to continue this story because I actually was told by another boy that his Mamma didn't think that the other boys Mamma was right in thinking that my Mamma was……….
Regards
Kruska
Lol - My Momma thinks your Momma is right -
Lol - My Momma thinks your Momma is right -
The email IS posted in its entirety Bill, nothing was left out or altered in any way. And you can contact Gene yourself if you don't believe me.
And as you can see in my email to him I directed him to read this thread.
Now I'm not going to play all hotshot on you Bill, don't worry, like you said no one is perfect. However I hope that from now on you'll keep your snide remarks to yourself and stop insinuating I don't know what I'm talking about.
So just admit defeat so we can get on with our lives man!
Thank you.
Hmmmmmmmmm
Not saying your right or not Soren (b/c I don't know), but you might of went to far rubbing his nose in it, IF you are right.
Stick to facts, if your facts are right.....no nose rubbing is needed. Facts speak louder then any gloating does. Your post is about 25% too much, rest is valid.
Bill,
I am not trying to pick sides, as you can see before this post of yours I was sticking up for you. But this post of yours comes across as you are discrediting Crumpp opinion after the fact.
Before when Soren said he would contact Crumpp you had no problem with him contacting him. Now it seems you don't like what Crumpp has to say so you are discrediting him with this comment.
What is it Bill? Do you respect Crumpps opinion or not? Seems you are flip flopping little.
I am trying to get facts from both of you, nothing else. I don't really care who is correct and who is wrong.