People who have regular access to an ERG will soon appreciate that holding a steady pace will give you the best times over a given distance. This translates accurately to rowing on the water. This has all to do with the Hull speed of the boat. Vessel drag in the water has two main components. Surface drag or friction and wave making drag. At slower speeds the friction makes up the largest portion of the total drag. As the vessel approaches its hull speed, more energy is used building waves and the wave making drag increases and exceeds the friction. The wave making drag is simply the distance between the bow wave and the quarter wave. When the wave length equals the waterline length the hull will have to start climbing the bow wave, essentially going up-hill. The diagram below shows power against speed . As the speed rises the power needed rises ever more sharply....
This is an approximated graph to demonstrate the general idea.
It can be quite easy to row at 4 knots, but you need to double your power input to get 5 knots and triple it to get 6 knots, about the maximum for the St Ayles. So in racing it is important to maintain a good sustainable pace, put extra effort into your start to burn off some energy but soon settle down and manage your race, often putting more effort in does not make the boat go much faster and you pay dearly later on in the race.
Boatspeed for a displacement hull is limited by the waterline length. The formula for this limitation is :
Vmaximum(knots) =1.34 x the square root (LWL in feet)
For a St Ayles Skiff with a waterline length of 17ft,
Vmaximum = 5.52knots or 2.84metres per second.
If we consider the results from the Skiffieworlds 2016, the best times achieved over the 2km course were around 12mins. Assuming the course length is accurate this equates to 2.7metres per sec or 5.24knots. This would be achieved with the boatspeed oscillating between a maximum of 5.5knots on the drive dropping to 4.98knots during the recovery at a stroke rate of around 32 strokes per minute. PS How do you paste graphs into the forum?