Breitling NAVITIMER AUTOMATIC GMT 41 Mode D'emploi page 52

Solution: With 156 miles on the mobile scale set opposite the hour index read the
speed in miles per minute, or the figure on the mobile scale which appears above
the figure «10» on the fixed scale which is 2 .6 miles per minute . There are times
when a pilot may want to know the time required to travel a short distance, such
as the distance from the cone of silence to the edge of an airport, or between
the inner marker and range station . Since the distance is short, the time required
may be less than a minute, in which case the time has more significance when
expressed in seconds . In such cases the «second» index is used . This is the figure
«36» on the inner scale (there are 3600 seconds in an hour) .
CALCULATING GASOLINE CONSUMPTION
Two of the following quantities are available for gasoline consumption problems:
Total gallons used, time, rate of consumption .
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Known: Time and rate of consumption . Required: Total gallons used .
A pilot wishes to know how many gallons are necessary to fly 31/2 hours at an
average rate of consumption of 111/2 gallons per hour .
Solution: Opposite the «hour index » set 11 .5 on the mobile scale . Then, opposite
of 31/2 hours (210 minutes on inner scale on the mobile scale) read 41 gallons .
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CALCULATING THE RATE OF CLIMB OR DESCENT
Two of the following quantities are available for solution: total altitude of descent,
time and rate of descent (or climb) .
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Known: Rate of ascent and total elevation in ascent . Required: Time .
A pilot climbs to 7400 feet above his starting point at the average rate of 500 feet
per minute . How long will this require?
Solution: Set 500 on the mobile scale opposite the «unit index» («10» on the fixed
scale) . Opposite 7400 on the mobile scale, read answer, 14,8 minutes on the fixed
scale .
CALCULATING THE DISTANCE OF CLIMB OR DESCENT
Two of the following quantities are available: Distance, time, speed .
The method used in examples 4 and 5 should be used .
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