A

Bullet
cross section area; A = pd^{2}/4 
a

Velocity
of sound in air, a = a(p,T,h) 
B

Symbolic
variable, indicating bullet geometry 
d

Bullet
diameter 
e_{c}

Unit
vector into the direction of the bullet' s longitudinal axis 
e_{t}

Unit
vector into the direction of the tangent to the trajectory 
g

Acceleration
of gravity; g = g(j ,y) 
h

Relative
humidity of air 
I_{x}

Axial
(or polar) moment of inertia of the bullet 
I_{y}

Transverse
(or equatorial) moment of inertia of the bullet 
l

Bullet
length 
m

Bullet
mass 
Ma

Mach
number 
p

Air
pressure 
Re

Reynolds
number 
r_{E}

Mean
radius of the earth; r_{E} = 6 356 766 m 
T

Absolute
air temperature 
v_{w}

Bullet
velocity with respect to wind system 
y

Altitude
of bullet above sea level 


a

Azimuth
angle 
d

Yaw
angle 
Q

Angle
of inclination of the trajectory 
r

Air
density r = r
(p,T,h) 
m

Absolute
viscosity of air; m = m(T) 
j

Degree
of latitude 
w

Spin
rate of bullet (angular velocity) 
w_{E}

Angular
velocity of the earth´s rotation; w_{E}
= 7.29^{.}10^{5} rad/s 