Vehicle Accel/Decel rates

[R_Kane]

OK, as it stands,a vehicle's standard accel(and decel)rate is 10% of its maxium speed. And since most vehicles inthe T20 book do not have Agility ratings above 0, their Max accel/decel rate is equal to their standard rate.

Under the vehicle combat section to change speed (up to max acel/decel) is a move-equivalent action...and since you can do 2 move actions per comabt turn, a driver can reduce his speed by 20% max speed per combat round.

So if each combat round is 6 seconds and you can reduce speed at 20% of max speed per round, if you are drivinf at max speed to start, it will take you 5 rounds to stop completely.

That is 30 seconds from max speed to complete stop. Does that seem too long to anyone else?

Also, I think that the computaion for max accel/decl should somehow take into account a vehicle's size as well as Agility. Large and bigger vehicles taking longer to stop, while Small and smaller vehicles take less time.

What are ohter people's thoughts?

-Roger

 

[R_Kane]

After thinking about it today, I came up with this mechanic for calculating vehicular accel/decel rates...

standard accel/decel = 10% of Max Speed + (vehicle Size modifier * 5kph)

Max accel/decel = std accel/decel * vehicle Agility

For example, say you have a Large sized (-1) TL15 Grav Cycle that has a max speed of 800kph and an Agility of 3.

std accel rate = .10(800kph) + (-1 * 5kph)
= 80kph + -5kph = 75kph

max accel rate = 75kph * 3 = 225kph

This way small agile vehicles will be able to accel and stop quicker and behemoth vehicles like battleships will take much longer to do the same.

Any comments? Please be kind...

-Roger

 

[R_Kane]

BTW, if a vehicle's Agility is zero, effectively max accel is equal to std accel

-Roger

 

[R_Kane]

Hmm..just noticed a problem...
If the vehicle Size modifier is big enough, say Enormous (-10) and slow enough, say max speed 100kph....my formula will result in a std accel rate of -40kph.

So, either the amount the Size modifier is multiplied by needs to be changed, or a general rule of thumb is that all vehicles have a minimum std accel/decel rate of 5kph.

<shrugs>
Like I said...any ideas/comments?
-Roger

 

[tjoneslo]

The ability to accelerate and decelerate is only rarely linked to vehicle size. Very few vehicles have the acceleration to reach max speed in one combat round, though many can stop that quickly.

If you'd like the more complex rules:
Accel/decel = (Agility + 1) * 10% * max speed.

Check the rules, I believe there is an "Emergency Decelerate" action as well.