Fletching-vanes in angles or not?
I read a study performed by NASA about vanes attached to arrowshafts in an angle to the longitudal axis. In this study it was stated that if the vanes was attached in an angle to the longitudal axis, it would result in more drag and less impact energy, compared to identical arrows with vanes attached parallell to the longitudal axis. The precision is not concerned weather parallell or in an angle.
How is the fletching tradition throughout Asia? Are the vanes parallel to the longitudal axis of the shaft, or in an angle?
How is the fletching tradition throughout Asia? Are the vanes parallel to the longitudal axis of the shaft, or in an angle?
Most arrows I have seen have had the vanes glued on parallel to the long axis of the shaft. This applies to Turkish arrows, Indo-Persian arrows, Korean arrows and late Qing Chinese. The old books in Arabic refer to attaching feathers in some cases at an angle. The arrows I saw that were said to be from the personal collection of the Qianlong emperor had a slight spiral to their setting on the shaft. These feathers were about 11 inches long and and carried down to within half an inch of the nock.
It seems that the purpose was to quickly correct the flight of heavy arrows used at close range. The very large feathers seen late Qing arrows served the same purpose. The loss in velocity was not considered to be problem. Arrows used for long distance shooting in most Asian cultures had straight-set feathers.
There are indications in the old literature that there were folklore beliefs about the special properties of feathers set at a slant. Sometimes they even wrote that they flew farther. However, these beliefs are on a par with the concept that spinning the arrow causes stabilisation in the same way the it does for a bullet. The moment of inertia for a long thin cylinder like an arrow does not provide the basis for spin induced stability. Spin does provide averaging of the path of the arrow which can be seen when many arrows are shot at the same target.
It seems that the purpose was to quickly correct the flight of heavy arrows used at close range. The very large feathers seen late Qing arrows served the same purpose. The loss in velocity was not considered to be problem. Arrows used for long distance shooting in most Asian cultures had straight-set feathers.
There are indications in the old literature that there were folklore beliefs about the special properties of feathers set at a slant. Sometimes they even wrote that they flew farther. However, these beliefs are on a par with the concept that spinning the arrow causes stabilisation in the same way the it does for a bullet. The moment of inertia for a long thin cylinder like an arrow does not provide the basis for spin induced stability. Spin does provide averaging of the path of the arrow which can be seen when many arrows are shot at the same target.
Thank You,
This is what I suspected.
This is what I suspected.
Tom
Have a read of this thread. There is also a link there to some wind tunnel tests of arrows with different fletchings.
http://www.ozbow.net/phpbb2/viewtopic.php?t=5646
Wind Tunnel Results:
http://www.ide-teknik.com/ewindtest3.htm
Regards
Grahame
Have a read of this thread. There is also a link there to some wind tunnel tests of arrows with different fletchings.
http://www.ozbow.net/phpbb2/viewtopic.php?t=5646
Wind Tunnel Results:
http://www.ide-teknik.com/ewindtest3.htm
Regards
Grahame