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20. Using the Register Ring
NOTE: The bezel design may vary depending on the model.
[Calculation function]
Note the following points when using this function. Use the calculation function of this watch only as a guide. These scales do not indicate the position of the decimal point.
Speed Index
Outer Scale (distance scale)
Inner Scale (time scale)
A. Navigational Calculation
1.Time required
Example: Obtain the time required for the fight of an aircraft at 180 knots for 450 nautical miles.
Answer. Align'18’ on the outer scale with the SPEEDINDEX /\ on the inner scale. Then, "45" on the outer scale corresponds to "2:30" on the inner scale (time scale). Thus, the time required for the flight is 2 hours and 30 minutes.
2.Knots (air speed)
Example: Obtain the knots (air speed) for 240 nautical miles with a flight time of 1 hour and 20 minutes.
Answer. Align ‘24’ on the outer scale with "1:20' on the inner scale (time scale). Then, the SPEED INDEX /\ on the inner scale corresponds to '18’ on the outer scale. Thus, the air speed for the flight is 180 knots.
3.Flight distance
Example: Obtain the air distance when the air speed is 210 knots and the flight time is 40 minutes.
Answer. Align ‘21'on the outer scale with the SPEEDINDEX /\ on the inner scale. Then, "40" on the inner scale corresponds to "14" on the outer scale. Thus, the air distance of the flight is 140 nautical miles.
4.Rate of fuel consumption
Example: Obtain the rate of fuel consumption (gallons / hour) when the flight time is 30 minutes and the fuel consumption is 120 gallons.
Answer. Align "12" on the outer scale with "30" on the inner scale. Then, the SPEED INDEX /\ on the inner scale corresponds to "24" on the outer scale. Thus, the fuel consumption is 240 gallons per hour.
5.Fuel consumption
Example: Obtain the fuel consumption required for a flight when the vats of fuel consumption is 250 gallons per hour and the flight time is 6 hours.
Answer. Align "25" on the outer scale with the SPEED INDEX /\ on the inner scale. Then, "6:00" on the inner scale (time scale) corresponds to "15' on the outer scale. Thus, the fuel consumption is 1,500 gallons.
6.Estimated flight time
Example: Obtain the estimated flight time when the vats of fuel consumption is 220 gallons per hour and the aircraft has 550 gallons of fuel.
Answer. Align "22" on the outer scale with the SPEED INDEX /\on the inner scales. Then, ‘55' on the outer scale corresponds to ‘2:30' on this inner
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