Chase-Durer Blackhawk Mach 3 - Manual (Page 6)

Looking beyond the 4 to the Tachymetre dial reveals the
chronometer hand pointing to 180. This means the average
speed of the car would be 180 MPH.
Let’s say, instead of the race car speed, you are measuring
something much slower like sailboat speed. In this case, you
need to use a shorter distance because the elapsed time must
fall within the 7.2-60 second range. For this example, let’s say
it took 36 seconds for your sailboat to travel 1/10 of a nautical
mile. Reading the Tachymetre dial gives a speed of 100 knots.
But, since we only traveled 1/10 of a nautical mile, the actual
answer is 1/10 of that or 10 knots.
Now let’s say you wanted to measure the speed of a very, very
fast airplane: after traveling 10 kilometres, you noted that 10
seconds had elapsed. The Tachymetre dial gives an answer of
360 but we traveled 10 kilometres. Therefore, the answer is
10 x 360, or 3600 km/hour.
There is really nothing magic about using the Tachymetre dial
to measure speed. You can also use it to measure other things
like gas consumption. Suppose it took 50 seconds to burn up a
gallon of gasoline. Reading the Tachymetre dial shows that you
are burning 72 gallons of gasoline per hour.
8
TACHYMETRE SCALE (cont.)
1 GALLON OF = POUNDS
alcohol
6.55
aviation gasoline 6.00
garbage
4.01
gasoline (auto) 6.14
jet fuel (JP-4) 6.50
kerosene 6.67
oil (lubricating) 7.59
oil (petroleum) 7.35
9
CONVERSION TABLE
ONE (1) =
barrel (u.s. oil) 5.62 cu.ft
barrel (u.s. oil) 42 gal. u.s.
foot
30.48 cm
foot .167 fathoms
foot .305 meters
kilometer 3280.84 ft
kilometer .621 stat miles
kilometer .540 naut miles
kilometer 1093.6 yards
knots 51.44 cm/sec
knot 1.69 ft/sec
knot .514 m/sec
knot 1.15 stat mi/hr
meter .547 fathoms
meter 3.28 feet
nautical mile 1012.7 fathoms
nautical mile 6076.12 feet
nautical mile 1.85 kilometers
nautical mile 1852 meters
nautical mile 1.15 stat miles
nautical mile 1 minute of lat.
nautical mile 1 minute of Great Circle