Citizen E610 Instruction Manual page 100

[Calculation of flight distance]
Q : If the speed is 210 knots and the flight time is 40 minutes, how many nautical
miles will an aircraft travel ?
A : Align 21 of the outer scale with the SPEED INDEX "  " of the inner scale.
Result: 140 Nautical Miles – 14 on the outer scale corresponds to 40 of the inner
scale.
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