boat size / crew weight

[ancho]

Spain is a traditional "lightweight-rower country".
We have many lightweight boats around and only few competitive heavyweight, so we often have to compete in lwt-boats in spit of being well above 72,5 kg average...

Now the question:
Can you quantify the influence of a hwt (lets say 90kg ave) crew rowing in a boat built for lwts (72,5kg ave)?
What influence do have the factors boat rigging, hull size, drag or others?
How can you compensate these affects? (other than dieting down to "salad muncher-weight")
Is it worse for a lwt crew to row in a hwt boat or vice-versa?

[Byron Drachman]

Hi Ancho,

If I understand the chart at Fluidesign website, it appears it's best to be too heavy (assuming you still have enough freeboard) rather than too light because you'll have less wetted surface, at least on a Fluidesign.

http://www.rowfluidesign.com/informatio ... rface.html

Actually, I think it is more complicated than just the amount of wetted surface. It also depends on the shape of the hull. I suspect that the amount of wetted surface is a good indicator of how much drag there will be, assuming the hulls have the same shapes for the different weight classes.


The river is finally unfrozen. Dang, it's great to be back on the water.

This is completely off topic, but would you like to see my 13-year old grand-daugher Karina, who has started speed skating?

http://www.youtube.com/watch?v=zjkPKsTZhKM

Byron

[PaulS]

Spain is a traditional "lightweight-rower country".
We have many lightweight boats around and only few competitive heavyweight, so we often have to compete in lwt-boats in spit of being well above 72,5 kg average...

Now the question:
Can you quantify the influence of a hwt (lets say 90kg ave) crew rowing in a boat built for lwts (72,5kg ave)?
What influence do have the factors boat rigging, hull size, drag or others?
How can you compensate these affects? (other than dieting down to "salad muncher-weight")
Is it worse for a lwt crew to row in a hwt boat or vice-versa?

1) For every 10kg increase in avg crew weight the hull will be sunk an additional 1cm.
2) This will lower the rigging height relative to the water, so you will have to have the additional height available to bring up the oarlock for proper clearances. Drag will be effected, but not terribly, and if the extra weight is useful muscle then having the weight is an advantage.
3) A lwt crew in a hwt boat, as long as they can balance and get the oarlock to the proper height, will do fine. Having additional clearance is better than not having enough.

If the crew is so heavy that they sink the bow underwater at any point during the stroke, then the additional drag of the water flowing over the deck would be very detrimental, but as long as that does not happen, you are likely going to be fine. Perhaps leading you to place the people in the boat so that the boat trims a bit to the stern if you are very close to the limit.

It seems that most pins accomodate about 2.5cm of adustment for the oarlock height, so about 12.5kg +/- from design capacity.

[Alissa]

The river is finally unfrozen. Dang, it's great to be back on the water.

This is completely off topic, but would you like to see my 13-year old grand-daugher Karina, who has started speed skating?

http://www.youtube.com/watch?v=zjkPKsTZhKM

Byron

Really fun to watch! Thank Byron. (Are you two trying to figure out a way that one of you can be on the river almost all the time? )

How long has she been doing this?

Alissa

[Byron Drachman]

The river is finally unfrozen. Dang, it's great to be back on the water.

This is completely off topic, but would you like to see my 13-year old grand-daugher Karina, who has started speed skating?

http://www.youtube.com/watch?v=zjkPKsTZhKM

Byron

Really fun to watch! Thank Byron. (Are you two trying to figure out a way that one of you can be on the river almost all the time? )

How long has she been doing this?

Alissa

Hi Alissa,

She started a few months ago. They're doing pickle bucket drills now, learning to get low. Their ice time is very limited. They get on the ice once a week for about 40 minutes and have one evening off-ice training session. As you know, cycling, rowing, skating are very compatible sports. Rowing and skating are hard to master technically. Actually, cycling is rather technical but it's possible to move fast without having nearly perfect technique.

Byron

[robhen]

PaulS is has got all the answers.

My double partner and I are getting are each getting a new single and we were measuring ourselves in a prototype single. I was 1 to 1.5cm deeper into the water then my partner however he is 13kgs lighter.

There is a truism that it is better to be overboated then underboated. And I always like to have plenty of height - around 17cm and my partner likes 15cm. But really all depends on how high the boat sits out of the water.

[Mike McGuirk]

The river is finally unfrozen. Dang, it's great to be back on the water.

This is completely off topic, but would you like to see my 13-year old grand-daugher Karina, who has started speed skating?

http://www.youtube.com/watch?v=zjkPKsTZhKM

Byron

Really fun to watch! Thank Byron. (Are you two trying to figure out a way that one of you can be on the river almost all the time? )

How long has she been doing this?

Alissa

Hi Alissa,

She started a few months ago. They're doing pickle bucket drills now, learning to get low. Their ice time is very limited. They get on the ice once a week for about 40 minutes and have one evening off-ice training session. As you know, cycling, rowing, skating are very compatible sports. Rowing and skating are hard to master technically. Actually, cycling is rather technical but it's possible to move fast without having nearly perfect technique.

Byron

Byron's grand kids can sing, too!

Byron, I never got around to telling you how much I enjoyed your submission to the Row2k/C2 video contest.

For those of you who didn't see it, here is a link.
http://www.row2k.com/features/features. ... =301&vid=9

MM

PS Glad to hear you're back on the water.