Pacenotes and Reconnaissance
Pacenotes are a unique and major tool in modern rallying. Television spectators will occasionally notice the voice of a co-driver in mid-race reading the pacenotes over the car's internal intercom. These pacenotes provide a detailed description of the course and allow the driver to predict conditions ahead and prepare for various course conditions such as turns and jumps.
In many rallies, including those of the World Rally Championship (WRC), drivers are allowed to run on the stages of the course before competition and create their own pacenotes. This process is called reconnaissance or recce. During reconnaissance, the co-driver writes down shorthand notes (the pacenotes) on how to best drive the stage. Usually the drivers call out the turns and road conditions for the co-drivers to write down. These pacenotes are read aloud through an internal intercom system during the actual race, allowing the driver to anticipate the upcoming terrain and thus take the course as fast as possible.
Other rallies provide organizer-created "route notes" also referred to as "stage notes" and disallow reconnaissance and use of other pacenotes. These notes are usually created using a predetermined pacenote format, from which a co-driver can optionally add comments or transpose into other pacenote notations. Many North American rallies do not conduct reconnaissance but provide stage notes through the use of the Jemba Inertia Notes System, due to time and budget constraints.
In the past, most rally courses were not allowed to be scanned prior to the race, and the co-drivers used only maps supplied by the organization. The exact route of the rally often remained secret until race day. Modern rallies have mostly converted to using organizer-supplied notes or allowing full reconnaissance, as opposed to racing the stages blindly. This change has been brought on in large part due to competitor demand.
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