How much faster is a light ski compared to a heavy ski?
This is a hotly debated topic that normally gets all emotional. Here is a more scientific approach.
For the technically minded read
http://www.atm.ox.ac.uk/rowing/physics/weight.html#section7
For the rest of us the result can be summarised as
“the percentage loss of speed is one sixth the percentage increase in mass.”
So how does this relate to the Tuesday night races?
Let’s take a 80kg paddler and a 15kg boat as the base case. The table below shows how the weight of the boat influences the speed. For a Tuesday night race where the winning time is around 25 minutes, the last column shows how many seconds you will win/loose because of a heavier or lighter boat.
|
Boat weight |
Total weight |
Change in
weight |
Change in
speed |
Time
difference over 25 minutes |
|
[kg] |
[kg] |
|
|
[seconds] |
|
10 |
90 |
5.26% |
-0.88% |
-13.2 |
|
11 |
91 |
4.21% |
-0.70% |
-10.5 |
|
12 |
92 |
3.16% |
-0.53% |
-7.9 |
|
13 |
93 |
2.11% |
-0.35% |
-5.3 |
|
14 |
94 |
1.05% |
-0.18% |
-2.6 |
|
15 |
95 |
0.00% |
0.00% |
0.0 |
|
16 |
96 |
-1.05% |
0.18% |
2.6 |
|
17 |
97 |
-2.11% |
0.35% |
5.3 |
|
18 |
98 |
-3.16% |
0.53% |
7.9 |
|
19 |
99 |
-4.21% |
0.70% |
10.5 |
|
20 |
100 |
-5.26% |
0.88% |
13.2 |
Bottom line is if someone is beating you by 27s you’re not going to beat them by getting a boat that weighs 10kg less. But if you beat your arch rival in a sprint finish then the few grand extra you paid for the boat was worth every single dollar.
Boasting
over a beer….priceless.
ps: There are still a few carbon Elites in
stock. They’ll give you about 15s on a Tuesday night with no extra training!!!