Indoors the thickest shaft the rules allow is the better choice

The summary today

There is a single argument, and it sits inside a calculation. The same engineer who studied the relationship between mass and diameter in carbon shafts starts from a scoring rule: an arrow that lands outside a zone but touches the line takes the higher value, so a thicker shaft is more likely to touch it. Outdoors that advantage is paid for in the wind, which moves thick shafts further; indoors, with no wind and a known distance, the cost disappears and the suggestion becomes the shaft at the largest permitted diameter, 9.3 millimetres under the World Archery rules cited in the paper. The advantage is not quantified, though, and the author puts it cautiously, as a possible gain. In the registry's bibliography nobody has calculated how many points it is worth over a sixty-arrow round, or compared shafts of different diameter by shooting them: the advice rests on the line rule and a model, and the registry has nothing else.

Also phrased as: "fat arrows indoors"; "large diameter indoor shafts"; "thick arrows cut the line"; "maximum shaft diameter indoors"; "indoor arrows"

Evidence

• 2013
  For Model Published later

  In his model of carbon shafts the author notes that an arrow touching the line takes the higher score, which gives thick shafts a potential advantage, "especially so for indoor competition where there is no wind". For indoor archery at known distances he therefore points to the shaft at the largest permitted diameter, 9.3 mm under World Archery rules (Fig. 7, pp. 241-242). The advantage is not quantified and there is no shooting.

  The impact of material selection on arrow design and optimal selection for competition · James L Park

Status history

1. 1990 Not studied No work in the registry's bibliography had yet looked at thick shafts for indoor archery in quantitative terms. The advice rested only on the scoring rule, under which an arrow touching the line takes the higher value, with no calculation or test: the claim had not been studied.
2. 2013 Transferred A model of mass and diameter in carbon shafts, which outdoors favours thin shafts because of the wind, suggests that indoors, with no wind and a known distance, the shaft at the largest permitted diameter is the better choice, 9.3 millimetres under World Archery rules, because a thicker shaft is more likely to touch the line of the higher score. The author presents it as a possible advantage and does not quantify it, and there is no shooting: the claim rests on a model, so it is transferred.

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