B&G Deckman - Manual (Page 74)

Advanced options
4.9
The format of the file is as follows
Vs RoT
2 4
6 12
10 15
12 20
15 20
where Vs is boat speed and RoT is rate of turn.
Acceleration
The timetospeed.d file allows you to predict your acceleration. A bit on
the theory behind this, though don’t worry if you don’t want to read it.
The acceleration times here are based on the wind angle at which you
are sailing, starting from your present TWA, and Deckman calculates
the change in the wind angle based on the rate of turn specified in
rateofturn.d. Deckman uses a logarithmic function to calculate the
acceleration, so that the times specified in the file should be those to go
from a slow speed to somewhere close to target upwind speeds.
In practice, the times you enter in the timetospeed.d file should be the
time taken to get from a ‘slow’ speed for the conditions to somewhere
near upwind target speed and, again, some reasonable value here is
likely to be better than none.
A sample file:
TWA T
0 20
40 40
80 35
120 30
160 30
180 35
where TWA is true wind angle and T is time.