Miscellaneous - Chase-durer COMBAT COMMAND Operation Manual

° °
At 68 F (20 C), sound travels at 344m or 376yds / 1,129ft per second in air at sea level.
°
Therefore, at 68 F (20 C) sound
1 mile (1,760 yards / 5,280 feet) in
1,000 yards in
1 kilometer in
To estimate the distance to an event (such as an
explosion, muzzle flash, lightning, etc.), measure
the time from the visual flash to the sound and
multiply the seconds by the per second speed.
For example the measured lightning to thunder
°
time at 68 F is 10 seconds. 10 x 344m or
376yds / 1,129ft would produce 3,440m or
3,760yds / 11,290ft. (2.14miles)
Alternately, you can divide the measured time at
°
68 F by 4.68 to get miles (10s / 4.68 = 2.14miles),
or 2.66 for thousand yard distance, or by 2.91 for
kilometers.
NOTE:
° °
At 32 F (0 C), sound travels at 332m or 363yds /
1,089ft per second in air at sea level.
°
Therefore, at 32 F (0
1 mile / 1,760 yards / 5,280 feet in
1,000 yards in
1 kilometer in

Miscellaneous

°
will travel:
4.68 seconds
2.66 seconds
2.91 seconds
°
C) sound will travel:
4.85 seconds
2.75 seconds
3.01 seconds
30
20
60
45 15
30
12
9
6
Example: Sea level temp is
lightning to thunder measured time is 18
seconds. Distance of lightning strike point
is:
18s x 1,129ft = 20,322ft
18s x 376yds = 6,768yds
18s x 344m = 6,192meters
OR:
18s / 4.68s = 3.85 miles
18s / 2.66s = 6.77 thousand yards
18s / 2.91s = 6.18 kilometers
7.
10
CHASE-DURER
FRI 31
COMBAT
COMMAND
AUTOMATIC
3
°
68 F and