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Wing-aspect-ratio
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Thumpalumpacus
Captain
Given that I've already acknowledged the last point, what exactly is baffling you?
Or are you just continuing to take the piss?
Either way, I apologize to others here for this crummy derail and will end my part in it.
ThomasP
Senior Master Sergeant
Hi Aspect Ratio wings, as mentioned above require less energy to generate the same lift at lower speeds, AND at higher speeds (hence the higher AR of the Ta152), as long as compressibility effects do not come into play, allowing both higher Vmax and maneuverability at altitude, and hence higher operational ceiling - everything else being equal. The main Hi Aspect Ratio effect re speed is to reduce the Vmax for a given power, so even if the Lo Aspect Ratio aircraft has just enough power advantage it can actually fly at the same altitude (ie has a Power Loading advantage that is great enough to make up for the higher drag of the Lo Aspect Ratio wing) the Hi Aspect Ratio aircraft will still be able to out turn the Lo Aspect Ratio aircraft and lose less altitude doing so.
Hi Aspect Ratio wings are more likely to encounter compressibility effects at lower speeds than Lo Aspect wings - everything else being equal.
Hi Aspect Ratio wings allow greater range than Lo Aspect Ratio wings, due to the lower energy required for the same lift and the fact that cruising speeds are usually significantly less than the Vmax (hence no compressibility effects encountered) - everything else being equal.
Hi Aspect Ratio wings, using similar construction methods to the compared Lo Aspect type, need to be heavier to counter the same Gs - everything else being equal.
In WWII most all the primary combat aircraft stalled at about 15° AOA (I think), regardless of Aspect Ratio, at least at higher speeds without the use of flaps or slots.
NOTE: Pretty much all the WWII higher speed aircraft encountered compressibility effects. The reason we do not hear more about the effects of this on aircraft such as the Spitfire, Mustang, Fw190, etc is partly that the Aspect Ratio was lower tor these aircraft than for the P-38 (as an example) and/or that the wings were of a lower Thickness-to-Chord Ratio. These factors, along with the wing planform, allowed some aircraft to deal with the compressibility issues relatively easily, at least in comparison to the P-38.
edit: Oops. I deleted the reference to the FW190D-9 having a greater wing span, as it was the same as for the A series??
Hi Aspect Ratio wings are more likely to encounter compressibility effects at lower speeds than Lo Aspect wings - everything else being equal.
Hi Aspect Ratio wings allow greater range than Lo Aspect Ratio wings, due to the lower energy required for the same lift and the fact that cruising speeds are usually significantly less than the Vmax (hence no compressibility effects encountered) - everything else being equal.
Hi Aspect Ratio wings, using similar construction methods to the compared Lo Aspect type, need to be heavier to counter the same Gs - everything else being equal.
In WWII most all the primary combat aircraft stalled at about 15° AOA (I think), regardless of Aspect Ratio, at least at higher speeds without the use of flaps or slots.
NOTE: Pretty much all the WWII higher speed aircraft encountered compressibility effects. The reason we do not hear more about the effects of this on aircraft such as the Spitfire, Mustang, Fw190, etc is partly that the Aspect Ratio was lower tor these aircraft than for the P-38 (as an example) and/or that the wings were of a lower Thickness-to-Chord Ratio. These factors, along with the wing planform, allowed some aircraft to deal with the compressibility issues relatively easily, at least in comparison to the P-38.
edit: Oops. I deleted the reference to the FW190D-9 having a greater wing span, as it was the same as for the A series??
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drgondog
Major
Fw 190D wing essentially Fw 190A wing. The primary difference was longer in-line Jumo an fuselage plug to extend the fuselage to maintain CG location.
The increase of wing span/AR for Ta 152 was to improve high altitude capability where Induced drag due to higher AoA required for level flight becomes more dominant.
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Metrallaroja
Airman
- 97
- Nov 21, 2020
Does anyone know why F8F SAC aspect ratio is 7.7?
If we do the regular calculation: (35,5x35,5)/244 = 5.16 aspect ratio
A big difference between 7.7 and 5.16. Why?
If we do the regular calculation: (35,5x35,5)/244 = 5.16 aspect ratio
A big difference between 7.7 and 5.16. Why?
Shortround6
Major General
Wild guess, the 7.7 aspect ratio refers to the propeller blade?
I have no idea why the wing aspect ratio is listed under the propeller blade information and not with other wing information.
I have no idea why the wing aspect ratio is listed under the propeller blade information and not with other wing information.
Metrallaroja
Airman
- 97
- Nov 21, 2020
No, is the wing aspect ratio I belive.
Jets SACs have the same.
Maybe structural aspect ratio?
How can I calculate that?
Metrallaroja
Airman
- 97
- Nov 21, 2020
Some more dimensions
Metrallaroja
Airman
- 97
- Nov 21, 2020
Metrallaroja
Airman
- 97
- Nov 21, 2020
I think it is just an error on the SAC
ThomasP
Senior Master Sergeant
The propeller blades used on the F8F-1 and F8F-2 had different planforms/chords. One of the types had an almost constant broader chord for most of the blade, while the other type was more tapered toward the tip. Unfortunately I do not know which was which.
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GregP
Major
Aspect Ratio is (span)^2/Wing Area, which works out to 5.141 . I'd have to look up the prop to check that one. Not tonight.
Getting back to the oríginal question. Aircraft testing should describe the actual flight characteristics that the tester finds. However, the tester's or writers opinions in a report might not reflect the real reasons for the characteristics. Note that professional Test Pilot training since WW2 places a heavy emphasis on Test Pilot technical knowledge so that they do not miss-attribute things that they find.
Anyway, you do need to read these reports carefully and pay attention to the actual characteristic that is described.
As regards wing A/R, some of the responses in this thread do reflect the characteristics of higher A/R in the subsonic speed range, with lower Induced drag being a large factor.
Also, the Germans were quite aware of the importance of high altitude bombing and fighting in the whole war. The Ju86P showed how the use of very high altitude was an important part of the flight envelope. German high altitude developments were considerable and successful, with high altitude power boosting GM1 and fantastic high altitude engines with complex supercharging. Although the relatively low operating MAP of the German engines suited the high altitude development, the special metals were still in short supply and most of the advanced very-high altitude engine projects had problems.
The Germans needed high altitude fighters to oppose the Allied high altitude photo recce aircraft.
Although very high mass bombing was not fully used, Mosquito bombers did operate at higher altitudes and their combination of high altitude and speed made interception difficult.
Various high altitude fighters were designed or prototyped. A fairly high fighter was the pressurised cockpit Bf 109 G1/3/5 and G5/AS. Using GM 1 they had enhanced altitude capability, although the special G5/AS anti-Mosquito units were not very successful.
Possibly, the most capable was the Ta 152 H with its high A/R wing and Jumo 213 which only appeared late in the war and was capable of 48,550'. Capt Eric Brown tested it and found the performance similar to the Spitfire Mk XIX, although he credited the Ta 152 H with better manoeuvrability above 35,000', probably a benefit of that fantastic high A/R wing.
Eng
GregP
Major
The Ta 152 was wonderful step forward in WWII piston super planes, but I'd not credit the Ta 152 with much of anything other than potential, which it very definitely had.
The total airframes completed amount to anywhere from 67 to 69 out of some 150 on which production was actually started, of which 42 or 43 were actually delivered to units, comprising Ta 152H-0, H-1, and C-1 airframes. It is claimed they were in production, but the first 20 were pre-production airplanes; basically prototypes that were 20 in number. That leaves 22 or 23 that might be classified as "production." If anything went bad, the aircraft was out of service and used for spare parts. When the war ended in Europe, there were exactly two Ta 152C's that remained operational. In total, the Ta 152s compiled anywhere from 6 to 9 or 10 victories (depending on who you believe) against anywhere from 2 to 4 combat losses (again, depending on which stories you believe).
By contrast, there were 225 Spitfire Mk. PR XIX built and delivered, they had a spare parts logistics chain established for maintenance, and went into regular squadron service. They weren't exactly numerous, but they were in huge number when compared with the actual appearances of the Ta 152 in combat.
None of the above disparages the Ta 152 airframe, which was exceptional. It just didn't have an effect on the war, and the war situation was such that the Ta 152 was unfortunately becoming operational right when the Luftwaffe collapsed as a fighting force in April 1945. There were a few Ta 152 sorties in Dec 44 and Jan 45, but most of the few Ta 152 combats were in April 45. It was also eclipsed by the Me 262.
It would have been pretty neat if the Allies had asked the Germans to produce a few Ta 152s post-war for evaluation and possible service, but the development of jets made that less than important. Just over 2 years after WWII was over, the U.S.A. was flying F-86s and the British were flying Vampire and Meteors, which made Ta 152s seem unnecessary as well as a bit obsolete. The Ta 152 was simply developed at exactly the wrong time for a piston super plane to make a splash.
Kind of like the Republic XP-72, which came right when (early 1944) super interceptors were not needed as much as long-range escort fighters were. So, the P-51H was developed and a few were built while the XP-72 was allowed to wither away despite being an aircraft with a lot of potential.
The total airframes completed amount to anywhere from 67 to 69 out of some 150 on which production was actually started, of which 42 or 43 were actually delivered to units, comprising Ta 152H-0, H-1, and C-1 airframes. It is claimed they were in production, but the first 20 were pre-production airplanes; basically prototypes that were 20 in number. That leaves 22 or 23 that might be classified as "production." If anything went bad, the aircraft was out of service and used for spare parts. When the war ended in Europe, there were exactly two Ta 152C's that remained operational. In total, the Ta 152s compiled anywhere from 6 to 9 or 10 victories (depending on who you believe) against anywhere from 2 to 4 combat losses (again, depending on which stories you believe).
By contrast, there were 225 Spitfire Mk. PR XIX built and delivered, they had a spare parts logistics chain established for maintenance, and went into regular squadron service. They weren't exactly numerous, but they were in huge number when compared with the actual appearances of the Ta 152 in combat.
None of the above disparages the Ta 152 airframe, which was exceptional. It just didn't have an effect on the war, and the war situation was such that the Ta 152 was unfortunately becoming operational right when the Luftwaffe collapsed as a fighting force in April 1945. There were a few Ta 152 sorties in Dec 44 and Jan 45, but most of the few Ta 152 combats were in April 45. It was also eclipsed by the Me 262.
It would have been pretty neat if the Allies had asked the Germans to produce a few Ta 152s post-war for evaluation and possible service, but the development of jets made that less than important. Just over 2 years after WWII was over, the U.S.A. was flying F-86s and the British were flying Vampire and Meteors, which made Ta 152s seem unnecessary as well as a bit obsolete. The Ta 152 was simply developed at exactly the wrong time for a piston super plane to make a splash.
Kind of like the Republic XP-72, which came right when (early 1944) super interceptors were not needed as much as long-range escort fighters were. So, the P-51H was developed and a few were built while the XP-72 was allowed to wither away despite being an aircraft with a lot of potential.
Don't want to be too pedant here or anything like that, but just for the sake of facts: there were never 225 spit pr19 operational before the Vday (8may45).
225 is the total production number (april44-Oct45)
With a fast look at the production list, there were maybe 20/30 assigned to squadrons before Vday starting june 44.
for the rest, i agree, except the that a 152 could still kick meteor's arse, this last one not being able to fulfill the manufacturer specs even in 46.
GregP
Major
Might be able to, if any were flyable and had decent pilots in them. Most Meteors, except for the first ones to fly, should have been able to outrun a Ta 152. The very early ones weren't really all that fast, so perhaps they would have been easier targets than later ones.
http://www.wwiiaircraftperformance.org/wade-comp-perf-chart1.jpg
http://www.wwiiaircraftperformance.org/wade-comp-perf-chart1.jpg
