Any advantage matters even if it’s too small

In the article “What is new on my opinion about rigging” I said that for the same rower we can have the same L1 and “e” in 1x, 2x or 4x, only L2 will be different, and it will also be bigger in 2x than in 1x and bigger in 4x than in 2x and 1x. Thus we have at least two advantages: 1) we can quickly adapt from single to double or to four oars; 2) the angle developed by the oar’s handle from catch to finish will remain the same, but the boat’s displacement while the oar is in water is different, namely: bigger in 2x than in 1x and bigger in 4x than in 2x and 1x.

Sportsman Popescu has the following parameters:
specific amplitude (A) (length of stroke) – 133cm (deduced from 140*95%);
shoulders breadth = 40cm
fist’s width = 9cm.
If after a classic rigging this sportive would have:

1x)   e=80(160)cm, L1 = 89cm, Gr = 2.25, L2 = 200cm, L=289cm

2x)   e=79.5(159)cm, L1 = 88.5cm, Gr = 2.27, L2 = 200.5cm, L=289cm

4x)   e=79(158)cm, L1 = 88cm, Gr = 2.29, L2 = 201cm, L=289cm

This rigging could be accepted by many specialists, let’s see what happens if we maintain the same L1=89cm and the same e=160cm in all of the boats, what will L2 (respectively L) for 2x and 4x be?

1x)   e=80(160)cm, L1 = 89cm, Gr = 2.25, L2 = 200cm, L=289cm

2x)   e=80(160)cm, L1 = 89cm, Gr = 2.27, L2 = 201.6cm, L=290.6cm

4x)   e=80(160)cm, L1 = 89cm, Gr = 2.29, L2 = 203.2cm, L=292.2cm

We notice that in the same case we have different burdening (drag) factor “Gr” for different type of boat. The “Gr” values have been taken from the rigging statisc from C.M. 2006. I’ve approached the Australian method of calculus

But let’s see what happens with the angles developed by the handle, the total angle (V), the attack angle and the release angle.

If we aknowledge that the distance between the handles of the oars at the finishing of the stroke is equal to the width of the shoulders minus the width of the two fists (40-18=22cm) we can calculate the angle of release (V2) and then by reducing from the value of V the value of V2 we can find out the value of V1.

The total angle V can be calculated using the formula:

Since the value of L1 is very close to the value of R we will use L1. The formula thus becomes

and

meaning

transforming we obtain V/2 = 48.347 and V=96.695 for 1x.
In the same way we calculate the angles for the others boats:

1x)   V=96.695, V2=39.169, V1=57.525

2x)   V=97.425, V2=39.284, V1=58.141

4x)   V=98.169, V2=39.400, V1=58.769

We notice that even in the clasic case the values of the angles are rising, both the attack and the realease angles.
In the case proposed by me the value of the total angle remains the same for all the boats, but so does the value of the angles of attack and release. But what’s happening with the boat’s displacement in the water during the drive phase? At 1x it stays the same, meaning = 233.087

2x   classic 158.5*sin39.284=100.356 and 158.5*sin58.141=134.621, Total 234.978

2x   new 159.6*sin39.169=100.805 and 159*sin58.769=135.958, Total 236.88

4x   classic 159*sin39.400=100.922 and 159*sin58.769=135.958, total 236.88

4x   new 161.2*sin 39.169=101.815 and 161.2*sin57.525 = 135.992, total 237.807

The numbers show a bigger displacement during the drive phase at all the types of boats, even though the angle remains the same, because L2 is bigger. It is also noticed that the angle of finishing the stroke is smaller than in the clasic rigging for 2x and 4x and the angle of attack doesn’t grow. The same geometry of movement is respected like in the 1x boat. The total angle is smaler, but with a bigger radius, the arc of the circle developed by the handle is less curved.

Conclusion: Because we do not have a reason that indicates that the new approach of the rigging is bad, we must have the courage to think and act outside the box and apply the new rigging that will result in an considerable advantage if we think about the aroximatively 250 strokes during the 2km race.

After the new calculus of the burdening (drag) factor we notice that in the case of the new rigging the stroke won’t be heavier but F1 grows for 2x, respectively 4x.