https://matteocampagna.com/en/registry/equipment/kyudo-grip-twist-arrow-landing Changes to this claim in Matteo Campagna's evidence registry: its status, its year-by-year history, revisions of the page. en-gb https://matteocampagna.com/en/registry/equipment/kyudo-grip-twist-arrow-landingThat twisting the grip of the Japanese bow changes the arrow's path was first said by a model, in 1997, and then by a test bench, in 2008. The three-link model, calibrated on a launching rig, finds that for the same total twist it is the timing that matters: change only the initial value and the trajectory changes completely, while arrow speed varies by less than one per cent. The test bench takes the archer out of the picture: bows of 13 and 15 kg on a mechanical launcher, a single duralumin arrow, a target at 28 m, and the torque applied to the grip alone, between zero and about 14 newton metres, is enough to move the landing point from one side of the target to the other. The relationship is not linear, and according to the authors too little twist pushes the arrow further off line than too much. The limits are real: it is a single outdoor test, with crosswind disturbing the data and no statistics at all, and nobody has yet measured, on the same shot, the twist an archer applies and where the arrow lands. Nineteen university practitioners, measured in 2007 with an instrumented bow, twist the grip about the bow's long axis by around 0.6 newton metres, but in that study the impact point of the shots is left out of the analysis; and on the launcher the torque, which acts about the same axis, reaches more than twenty times as much, so much of the tested curve lies outside what people do when they shoot.claim:tenouchi-torsione-direzione-freccia:revision:2026-09-14:2Mon, 14 Sep 2026 08:00:00 GMT https://matteocampagna.com/en/registry/equipment/kyudo-grip-twist-arrow-landingclaim:tenouchi-torsione-direzione-freccia:new_claim:2026-08-07:riportatoFri, 07 Aug 2026 08:00:00 GMT