General Report on Tunny

25F Page 171

of Χ₂ limitation; but insufficiently to do more than justify separate decibanning against Χ₂ cross and Χ₂ dot, both being used. The ΔD letter 5 is peculiar in scoring better against Χ₂ dot than against Χ₂ cross. (22H(d)) (R3 pp 10, 59.)

25F SPECIAL METHOD FOR ab ≠ ½

	PB (ΔD_i = .)	= PB (ΔΨ'_i + ΔP_i = .)
		= β_i π_i

where β'_i is the proportional bulge of ΔΨ' = ., so that if ab ≠ ½, single wheel initial Χ - breaking runs are possible.

The resultant wheel is of course a true ΔΧ wheel and not a horrid hybrid like .

The rule ab = ½ was introduced in March 1942. In one later instance the limitation on a machine used by the Stickleback link became inoperative; this in effect doubled the motor dottage, making ab ≠½ and β'_i = β.

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