A Guide to Time - Speed - Distance
A Time-Speed-Distance (TSD) rally is a competitive motorsport event, run on open
public roads
at legal speeds.
A TSD rally is not a race; it is a precision driving competition. The basis of
the
competition is
the accurate application of complex rules under time pressure to follow a
designated route
in a set period of time. The route is described in written instructions that
include assigned
speeds for multiple intervals in the rally. The written instructions are
somewhat
“coded” by use of
abbreviations or graphics. In addition to rapidly interpreting the
instructions,
competitors must
be adept at applying default rules when necessary. Teams set out from a
starting point at
one-minute intervals and are timed at established locations, although the
locations are not
given in the instructions. A TSD rally typically includes multiple “legs” or
regularities,
ranging from five to 20 miles, which are separately scored. Teams accumulate
penalty points
for arriving early or late at the timing locations; penalty points also accrue
for
going off course.
The team with the lowest number of penalty points is the winner.
TSD
rally teams consist of two members: a driver and a navigator. Since there are
three roles in
the car (driving,
navigating, and timekeeping), the navigator typically also keeps time and the
driver must
contribute to keeping on course. The most accomplished rally teams are
completely
familiar with the
rules, well-practiced at their work, and communicate very well. People who are
competitive,
quantitative, detail-oriented, and focused enjoy TSD rallies.
The
organizing body that puts on a TSD rally will define the cars and the equipment
that may be
used in the
rally; there may also be classes based on the experience level of the team,
from
novice to expert.
Depending on the rally, the cars may be highly specialized and prepared or
may be everyday
drivers or classics. While having a special rally car may sound like an
advantage, the
overwhelming factor in TSD rally success is the team, not the car. As long as a
car can
adequately accelerate and brake, a good team can win with it; a poor team will
do poorly
with the best of
cars. Comfort, outward visibility, and reliability are more important than raw
performance.
TSD
rallies typically have a range of classes based on the type of rally equipment
used. At the
most basic, the
un-aided or “seat of your pants” or SOP class does not allow any speed or distance
measuring equipment other than what came on the car originally, does not
allow the use of the car’s original computer to calculate average speed,
and does not allow the use of any calculating devices
(except paper and
pencil). The highest class might allow the use of specialized sophisticated
computer systems
that measure distance independent of the car’s original equipment, keep time,
and calculate how
early or late the team is relative to the ideal time. In the middle are classes
that allow
various kinds of calculators, but depend on original odometers and
speedometers.
A
TSD is some of the most fun you can have on the road, in your car, while
staying in legal speeds. It is a puzzle that both you and your partner are
responsible for solving while others compete to finish it more
accurately than you.
Please check out this write up by one of our newest rally teams of
their participation in the 2021 Northwest Classic Rally for their
explanation of a TSD and their experience.
Feeling nervous about driving your first TSD rally or looking to fine tune your skills? Try joining us in the AROO Cup series and school.