310_Snakes napsal:

Takže B-čkovej Mustang měl od 360mph IAS (580km/h) lepší roll rate než FW 190A? Řek bych že Fučida to tak nenechá ....

Wolvercorte napsal:

Ahoj.
Zajímalo by mě, jestli cítíte nějaký rozdíl v létání třeba s Mk. IXc a s Mk. IXc CW.
Já totiž žádný necítím, ale to bude nezkušenost.
Jaký vůbec byl význam těch useklých křídel? Byl to experiment? ('Cutwingů' byly mám pocit 3 typy - osmička, devítka C a devítka E)
(Chápu, že existuje google, ale mám rád podměty k diskusi)

Jinak důvod useknutí křídel byl zvýšeni rychlosti a obratnosti u země.

From The Spitfire Story by Alfred Price, part of an AFDU test from 1942:
Two Spitfire VB aircraft were selected with a performance which was almost identical, the loading and equipment car¬ried were standard in each, and the propeller, engine and finish of each aircraft were similar. A test flight was made under maximum cruising conditions and no differences could be determined. The wing tips were then removed from one aircraft and trials were carried out, each trial being performed twice to enable the pilots to be changed. The wing tips were then replaced on one aircraft and removed on the other and similar tests carried out. Differences in speed were taken as relative increases or decreases owing to possible instrument inaccuracies, and position error differences with and without tips. Readings for level speeds were taken at 10,000,15,000, 20,000 and 25,000 feet; zoom climbs were made 10,000-15,000 ft and 20,000-25,000 ft; dives were made with similar engine settings.

Results of Comparative Tests

Level Speed
10,000 feet. In each case the clipped wing Spitfire proved the faster by a small margin estimated in the nature of 5 mph.
15,000 and 20,000 feet. The average results at these two heights showed that the difference in speed is not measur-able.
25,000 feet. The standard Spitfire is very slightly faster than the clipped wing Spitfire.
In all level speed runs the clipped wing Spitfire accelerated rather better than the standard Spitfire.

Climb
The average difference in time during zoom climbs from 20,000 to 25,000 feet was 15 seconds in favour of the stan-dard Spitfire.
From 10,000 to 15,000 feet no differences were indicated.

Dive
In all diving tests the clipped wing Spitfire drew away from the standard Spitfire.

Manoeuvrability
At all heights to 25,000 feet the rate of roll is considerably improved by removal of the wing tips. The response to aile-ron movements is very quick and very crisp. Four dog-fights were carried out, starting with the standard Spitfire on the tail of the clipped wing Spitfire. On two occasions the clipped wing Spitfire evaded so rapidly in the rolling plane that it was able to lose the standard Spitfire and reverse the positions in about 20 seconds. On the third occasion the clipped wing Spitfire was also able to lose the standard Spitfire. The fourth occasion was at 25,000 feet and the standard Spitfire was able to keep the clipped wing Spitfire in sight.
The minimum turning circle of the clipped wing Spitfire at 20,000 ft has been increased by 55 feet at 1,025 feet com¬pared with the FW 190 turning circle of 1,450 feet (RAE Farnborough figures). This slight increase does not therefore detract from the fighting qualities of the aeroplane in any way, since the clipped wing version is unlikely to be in com¬bat with the standard Spitfire.

Take-off
The take-off run must theoretically be slightly longer, but in taking off with the clipped wing Spitfire in close formation behind the standard Spitfire, no difference was detected. Landing
No difference detected.

General
The view downwards over the wing tips, for what it is worth, is improved by a not inconsiderable amount. The strengthening of the wing by removal of the wing tips mav permit higher maximum IAS to be used.

Rumcajs napsal: Otázka teda je, proč to tedy používali.

Rumcajs napsal: Nebylo víc verzí Clipped Wings?

Rumcajs napsal:

To je zajímavý dokument Farky. Jsem to přečetl a v zásadě podle toho dokumentu neexistuje smysluplný důvod zavádět clipped wings. Jediné zlepšení bylo u toho Spitu XII E.N.221. Jinak je celý výsledek velmi negativní. Marginální zlepšení rychlosti u země. Drobné zlepšení roll rate v některých případech. Vykoupeno horší manévrovatelností, dostupem, stoupavostí, vyšší pádovkou, delším startem. Otázka teda je, proč to tedy používali. Páčto test je z přelomu let 42/43. A v 1944 s tím podnikli invazi a bojovalo to do konce války. Nebylo víc verzí Clipped Wings?

Rumcajs napsal:
Ano Seržo, roll rate není konstanta, mění se s rychlostí. U každýho typu letadla (a verze) je to jinak. Dokonce záleží na tom, kolik máš paliva a nábojů v křídlech a jiných navěšených kravinek.

LesniHU napsal:
U Spitu se to komplikuje zmenami v potahu kridelek (plateny potah se vybouloval a zvysoval potrebne sily), zmenami geometrie samotnych kridelek (mkVIII pokud se nemylim a pak jeste ?mk21?) ci jejich typu (21) a zmenami v konstrukci kridla, ktere zvysovalo torzni tuhost.

Hoper napsal:

A i takový P-47 měl velmi slušný roll rate, čehož prý využíval Gabresky při boji s FW.

LesniHU napsal:Ne, to ne. Kolik je hmotnosti v kridle nema vliv na [ustalenou] rychlost vykrutu, coz je to, co se tady resi.

Powerty napsal:



Hlavně se 109-kama, které měly oproti jugu daleko lepší zatáčku. Sudový výkrut na vnější stranu zatáčky ho udržel na 6-té.