Angular momentum when launching projectile

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Homework Statement

For a space-based platform B launching a projectile A what are the resultant inertial velocities equations and where do the launch location and projectile end up a little after launch? The platform is rotating and moving thru space and the launch mechanism imparts a fixed N*sec impulse to the projectile. The projectile is not located at the platform CG and the impulse does not act thru the platform CG.

Homework Equations

Ignore gravity, drag, and launcher friction
Impulse acts at projectile CG
mB = platform mass (mA for projectile)
PB = platform initial inertial position of CG (PA for projectile)
VB = platform initial inertial velocity of CG (VA for projectile)
wB = platform initial inertial rotation rate about its CG (wA for projectile)
IxxB = platform moment of inertia (IxxA for projectile)
F = applied impulse force to projectile at time zero
dt = time period after launch to calculate the launch and projectile location
R = distance vector from platform CG to launch location (i.e. projectile CG at launch)

The Attempt at a Solution

These are vectors...
Pre-launch:
VA = VB since they are attached
wA = wB since they are attached
R = PA - PB
After launch:
VB(t) = VB - F / mB this is a constant
PB(t) = PB + VB(t) t
wB(t) = wB - F x R / IxxB this is a constant
VA(t) = VA + F / mA + wB(t) x R this is a constant
PA(t) = PA + VA(t) t
R(t) = R rotated (wB(t) t)

Launch location: PL(t) = PB(t) + R(t)
Projectile location: PA(t)

4. Should I be including more of the parts shown in https://www.physicsforums.com/showthread.php?t=77434
aA = aB + wBdot x R + w x (w x R) + 2 w x VRel + aRel

 

[BigJDubs]

No, this equation is only appropriate for the acceleration of the projectile relative to the platform. The equations above are appropriate for the velocities and positions.