Wing-aspect-ratio
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GregP
Major
The aspect ratio has an effect on handling, as does span loading.
All else being equal, a higher aspect ratio will lose less speed in general in a level turn (or any turn, for that matter) but may not turn as quickly if the wing areas are the same, at least down low. So, a low-aspect ratio plane like the post-WWII U.S. F-106 was a VERY good turner, but it would lose speed rapidly when doing so. Same for the French Mirage II family as well as others. In WWII, most fighters ... well, most monoplane fighters anyway, were in the aspect ratio neighborhood of 5.5 - 8.5 and were mostly around 5.8 - 7.8. Aspect ratio is the span divided by the mean chord, but you can get the effective aspect ratio by (span^2 / wing area). If you use meters for the span than use square meters for the wing area ... if you use feet for the span then use square feet for the wing area. The average aspect ratio for monoplane fighters was about 6.0.
Note above I said "all else being equal." So, if we have two airplanes with the same weight and wing area and engine and propeller, the one with the higher aspect ratio will lose less speed in a level turn and thus will require less power to remain level in a turn at constant speed. Thus, if it is not using full power in the turn, it has more excess power available to climb while turning. The lower aspect ratio plane will usually roll more quickly, but will lose out in retaining energy in a turn.
The designer has to make choices based on the anticipated role for the airplane.
Biplanes seem like their aspect ratio is out of whack, but that's because they have two wing areas in a single span.
Again, all else being equal, the plane with the lower span loading should be more maneuverable at high altitude. But, things are relative. I have seen a thread where someone asked why the P-47 was so fast. In fact, it wasn't. But it had a VERY GOOD turbocharger system that maintained good power as it went higher. So, it was one of the better high-altitude fighters for a variety of reasons, but primarily because it had very good power at higher altitudes. The span loading was about 1/3 higher than for the P-51 Mustang, but the relative power the P-47 maintained as it got higher more than made up for the span loading increase.
All else being equal, a higher aspect ratio will lose less speed in general in a level turn (or any turn, for that matter) but may not turn as quickly if the wing areas are the same, at least down low. So, a low-aspect ratio plane like the post-WWII U.S. F-106 was a VERY good turner, but it would lose speed rapidly when doing so. Same for the French Mirage II family as well as others. In WWII, most fighters ... well, most monoplane fighters anyway, were in the aspect ratio neighborhood of 5.5 - 8.5 and were mostly around 5.8 - 7.8. Aspect ratio is the span divided by the mean chord, but you can get the effective aspect ratio by (span^2 / wing area). If you use meters for the span than use square meters for the wing area ... if you use feet for the span then use square feet for the wing area. The average aspect ratio for monoplane fighters was about 6.0.
Note above I said "all else being equal." So, if we have two airplanes with the same weight and wing area and engine and propeller, the one with the higher aspect ratio will lose less speed in a level turn and thus will require less power to remain level in a turn at constant speed. Thus, if it is not using full power in the turn, it has more excess power available to climb while turning. The lower aspect ratio plane will usually roll more quickly, but will lose out in retaining energy in a turn.
The designer has to make choices based on the anticipated role for the airplane.
Biplanes seem like their aspect ratio is out of whack, but that's because they have two wing areas in a single span.
Again, all else being equal, the plane with the lower span loading should be more maneuverable at high altitude. But, things are relative. I have seen a thread where someone asked why the P-47 was so fast. In fact, it wasn't. But it had a VERY GOOD turbocharger system that maintained good power as it went higher. So, it was one of the better high-altitude fighters for a variety of reasons, but primarily because it had very good power at higher altitudes. The span loading was about 1/3 higher than for the P-51 Mustang, but the relative power the P-47 maintained as it got higher more than made up for the span loading increase.
drgondog
Major
The only important calculation involving Aspect Ratio is that for Induced Drag - particularly at low speed to Cruise. At high speed, CDi is very low.
Aircraft designed for long range will typically have very high AR, Interceptors/Fighters medium to low.
Aircraft designed for long range will typically have very high AR, Interceptors/Fighters medium to low.
Thumpalumpacus
Major
Perhaps because they were facing a high-altitude heavy bombing campaign.
The wings on both aircraft were designed long before any US high altitude bomber arrived in Europe.
Thumpalumpacus
Major
I was thinking more about the FW-190D and Ta-152. Perhaps they arrived at those designs due to earlier testing -- and made a design decision under the pressure of a high-altitude bombing campaign?
Or perhaps you think the Germans weren't really worried about 8th AF, I don't know. <shrug>
The post you replied to just said Me109 and Fw 190 so that is what I am discussing. To my knowledge neither were designed as interceptors, at the time of their design the Germans were not bothered at all about any USA bomber force, the force didnt exist and Germany wasnt at war with USA, and in any case where would they bomb from, the UK would be in German hands (if anyone actually thought that far in 1936-39)
Thumpalumpacus
Major
That's great. I'm not talking about their original incarnations, which should be obvious from my reference to high-level bombing -- which we all know didn't take off in earnest until 1943.
I was addressing the OP's question of why the Germans put emphasis on HAR wings. I didn't see that he had a cutoff date.
I rather expect readership to gather inferences. Sorry that didn't work out in this case for you.
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Thumpalumpacus
Major
Look at the wings. That is, after all, the topic.
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Thumpalumpacus
Major
The OP did not mention dates, and I was replying to him, not you.
Your mention of the 8th Airforce brings in a date or dates. The German declaration of war and the appearance of the US bomber forces. The FW190D first flew just 2 months after the USA forces first appeared, they cannot be connected. The FW190 was certainly a high altitude version, but not in response to the US bomber campaign.
Thumpalumpacus
Major
Okay. So perhaps it was high-altitude Spitfire recons, of Mossies, great.
Wouldn't it have been easier to simply say as much rather than to try and take the piss? Here, here's a sample response:
"You know, Thump, the Germans faced other high-altitude threats before 8AF entered the fray. That might have driven their interest as well."
Not very difficult, and it makes for an easier and more informative discussion than this crap. I'll go look up the origin of HAR wings in the LW, and I'll remember how ham-handed you can be dealing with folks.
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Thumpalumpacus
Major
And you apparently missed the first word in my post: "perhaps". That indicates uncertainty. And my follow-on reply made clear that I was thinking later in the war rather than when the 109 or 190 were designed.
Never mind this conversation. You're being deliberately obtuse and that doesn't merit any more time from me.
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Thumpalumpacus
Major
Yes, and my "perhaps", as already pointed out, was your clue that I wasn't certain.
I don't like the way you're addressing me and am pointing that out. Don't like it? Tough. Treat me with courtesy and you'll get courtesy in return. That's my standard; I nake change in the coin tendered.
If that's "hurty" to you, who cares? I sure don't. I don't know you from a can of paint and don't assign any significance to your opinion of me. If you don't like my insisting on being treated courteously, put me on ignore.
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Thumpalumpacus
Major
The difference between you and I is that you think of this as a game to be "won", while I'm looking for intelligent discussion.
Looks like we'll both be disappointed.
