$CF$

generic force coefficient

$Cfh$

coefficient of rms propeller horizontal force

$Cfr$

coefficient of rms propeller resultant force

$Cfy$

coefficient of rms propeller side force

$CM$

generic moment coefficient

$CMz$

coefficient of rms body yawing moment

$Cth$

thrust loading coefficient

$D$

propeller diameter

$Dh$

model hull diameter

$F$

generic force component

$Fx$

force component on body in $x$ direction

$Fy$

force component on body in $y$ direction

$Fz$

force component on body in $z$ direction

$f$

hydrodynamic frequency

$fx$

force component on propeller in $x$ direction

$fy$

force component on propeller in $y$ direction

$fz$

force component on propeller in $z$ direction

$J$

advance ratio, $J=V\u2215nD$

$L$

model hull length

$M$

generic moment component

$Mx$

moment component on body in $x$ direction

$My$

moment component on body in $y$ direction

$Mz$

moment component on body in $z$ direction

$mx$

moment component on propeller in $x$ direction

$my$

moment component on propeller in $y$ direction

$mz$

moment component on propeller in $z$ direction

$n$

propeller rotational speed

$nsp$

propeller rotational speed at self-propulsion point

$q$

dynamic pressure

$Rprop$

propeller radius

$r$

radial distance from hull centerline

$t$

time

$t0$

time of propeller direction reversal

$U$, $V$, $V4$

free stream velocity

$u$

mean streamwise velocity component

$u\u2032$

fluctuating streamwise velocity component

$v$

mean radial velocity component

$v\u2032$

fluctuating radial velocity component

$x$

coordinate direction parallel to body axis, positive forward

$y$

coordinate direction perpendicular to body axis, positive starboard

$z$

coordinate direction perpendicular to body axis, positive down through keel

$\eta $

ratio of actual propeller rotational speed to speed required for self-propulsion, $\eta =n\u2215nsp$

$\rho \u221e$

fluid density

$\sigma $

standard deviation

$\omega $

reduced hydrodynamic frequency

$\omega p,FFT$

reduced hydrodynamic frequency at peak fast Fourier transform (FFT) amplitude of propeller side force