Wolfram only goes as far as Multiples of Light-speed, not AU/sec^2 or LY/sec^2 which seem to be some of the main velocities I need.
Okay, so it sounds like it is
acceleration that you want, not velocity. Velocity is how fast you're moving (distance per time) while acceleration is how fast your velocity is changing (distance per time squared.) Acceleration is what you're doing by scrolling the mousewheel in the spaceship/airplane mode.
To compute the acceleration you need in order to make a trip of a certain distance in a certain amount of time, you'll need a formula. (Where does this formula come from? Calculus).
[tex]a=\frac{2D}{t^2}[/tex]
In words, "twice the distance divided by the square of the time".
Wolfram Alpha can do this for you very quickly. Suppose we want to travel 1AU in 30 minutes. In Wolfram Alpha, enter:
(2*1AU)/(30 minutes)^2
and we get
92344 m/s^2
We can also get the answer in AU or other units. For example, say we want to go
53.53 LY in 45 mins, and we want the answer in AU/sec^2. Then enter
(2*53.53 LY)/(45 minutes)^2 to AU/s^2
and we get
0.9288 AU/s^2