Does Sequential Rowing Increase Boat Speed?

[Neandethal00]

After watching a few rowing competitions of London Olympics 2012, a question came to my mind.

In the competitions rowers (Not sure if this is the word used for athletes) synchronize their
rowing strokes. All 8 athletes' oars touch and leave water at the same time. This causes the boat to accelerate faster but then to slow down significantly when oars are out of water.

My question is will the boat eventually move faster if athletes row the boat in pairs, one pair after another? When oars of the first pair about to leave water, next pair will hit the water, when 2nd pair about to leave water, 3rd pair's stroke will begin...etc. In such case there will be no deceleration.

This can easily be proved by some simple Math. Hope some one has already done the work and let us know why the synchronized rowing is better.

My personal guess is athletes should start with synchronized strokes, when they attain a certain speed, then they should switch to sequential strokes.

 

[sophiecentaur]

But wouldn't the oars CLASH? The length of stroke is huge.

 

[Neandethal00]

But wouldn't the oars CLASH? The length of stroke is huge.

Good point, I didn't think about oars clashing.
Will they clash? Wait a minute. Clashes can be avoided. There are 4 pairs of rowers.
They can row in this sequence..

First pair --> 3rd pair --> 2nd--> 4th--> first

or

2nth --> 4th --> 1st --> 3rd --> 2nd

When 3rd pair is about to finish the stroke, 2nd pair will begin. Oars positions will be widely separated.

I think there may be other reasons for synchronized strokes.

 

[mfb]

I think coordination is a very good reason. It is easy to keep all in sync. 4 different phases for rowing would be quite complicated.

 

[256bits]

Clashing is a very good reason. You could make the boats longer to avoid clashing and a new Olympic event could exist.

One other is the pace, or rows per minute. It is much easier to 'pick up the pace' when synchronized, as you all follow along in unison.

Another is psychological. As a team you act as a unit and give it all you got in a team effort. Sequential rowing I think would make the rowers think that one of the other guys is not pulling his/her fair share.

 

[rollcast]

Also if they are all pulling together it sort of evens out the effect if one of the rowers was stronger than the others or pulled harder by ensuring the pull equally at the same times.

 

[willem2]

Even if the oars don't clash(such with a pair, 2 rowers and one oar each) the rowers are movin from front to back on their rolling seats, and will have to do this at the same time, or poke the rower in front of them n the back with their oar handles)

 

[AlephZero]

Watch some videos carefully, especially "long distance" shots that show the wake of the boar and the position of the oars in the water on sucessive strokes. For eaxmple a rowing eight travels more or less the full length of the boat for each stroke when going at full speed.

The geometry of your ideas won't work. To a rough approximation, the oar blades are stationary relative to the the water, and the lever arm of the oar and the sliding seat moves the boat relative to the oars.

This is a completely different situation from rowing a small dinghy with a fixed seat, using short oars with small blades.

 

[sophiecentaur]

Good point, I didn't think about oars clashing.
Will they clash? Wait a minute. Clashes can be avoided. There are 4 pairs of rowers.
They can row in this sequence..

First pair --> 3rd pair --> 2nd--> 4th--> first

or

2nth --> 4th --> 1st --> 3rd --> 2nd

When 3rd pair is about to finish the stroke, 2nd pair will begin. Oars positions will be widely separated.

I think there may be other reasons for synchronized strokes.

Although the blades going backwards in the water would be lower than the blades traveling forwards out of the water, they work with as little water clearance as possible. It would be necessary to have the vertical positions of all the blades kept very accurately to avoid bashing each other - whatever fancy interleaving system you could devise. Those oars are very long and hard both to control and apply power at the same time.

And then there's the sliding seat problem - as already mentioned.

Also, I think that putting a blade in 'dirty water' from a previous stroke that someone made would make it hard to maximise the power that you could put into a stroke. (Compare how easy it is to row in flat water compared with choppy water). Races are won or lost on many different factors.