Drafting

George's posts always make me a bit sad. There are many open water races that are lost to history or reside only in the memory of the people who were in them and yet they often have colorful stories attached. In racewalking, my first love, there are huge gaps in the history. Not just the origin, which is long lost, but even some of the US national championships of years past and some of the crazy things that happened during the races. George, not to make work for you, but you really should consider writing up your race career - even the races covered in Wind, Waves and Sunburn. It wouldn't have to be a book or formally written, per se - even just an introduction and a page on each race that you could remember and then send xerox copies to universities that have Sport History programs. Some day there will be a doctoral student writing his/her dissertation on the history of open water swimming who will thank you. -LBJ

Originally posted by Leonard Jansen George, not to make work for you, but you really should consider writing up your race career - even the races covered in Wind, Waves and Sunburn. It wouldn't have to be a book or formally written, per se - even just an introduction and a page on each race that you could remember and then send xerox copies to universities that have Sport History programs. Some day there will be a doctoral student writing his/her dissertation on the history of open water swimming who will thank you. -LBJ So many races so many stories. Every race had a story some were funny and some not so funny. In Egypt I led a race for 42k and ran into a swimmer behind a large bouy. He had been withdrawn from the race in the first part of the race. He appeared from nowhere. He pulled away from me as if he had just entered the water, (because he had). No one else passed me and I came in sixth. In the boat that was beside me I had someone from the Canadian consulate to give me my nourishment. I asked him to lodge a complaint, he said no he did not want to cause an incident for the Canadian government. I later talked to three other Egytian swimmers about this and their reply to me was they knew who was going to win the race so they got out. I did however have a great all expense paid holiday and lots of sponsor ship money. I was told not to complain or I would not be Invited to swim in the races sponsored by the International Professional Swim Federation, which controlled all races outside of Canada or the USA. George ww.swimdownhill.com

Originally posted by Leonard Jansen There are many open water races that are lost to history or reside only in the memory of the people who were in them and yet they often have colorful stories attached. George, not to make work for you, but you really should consider writing up your race career - even the races covered in Wind, Waves and Sunburn. It wouldn't have to be a book or formally written, per se - even just an introduction and a page on each race that you could remember and then send xerox copies to universities that have Sport History programs. Some day there will be a doctoral student writing his/her dissertation on the history of open water swimming who will thank you. Sounds like a great continuing comentary for the USMS magazine: "Park's Place". If George is willing, write up a short story every two months, and pick up some pocket change for the effort. :) (I realize he is from Canada, but I agree, these stories would make fascinating reading.)

From what I have been told of those swims in the old days of marathon swimming....George would have some great stories to share with us all.....How about it George...?

I will gladly share some of my experiences, and some of the stuff about my older brother Tom and some other guys that swam in my time, like Dennis Matuch the Chicago cop, Cliff Lumsden. George Young, the Black Shark Earnest Verkotter, the hunan windmill Gambi the Italian who stroked 100 strokes a minute from an earlier time. You do understand that Canada was where Marathon races started and some of the greatest marathon swimmers came from. George

My understanding of the physics of drafting in motor racing is that both the drafter AND draftee experience fuel savings as a result of drafting. The leader experiences less back end "suction" from air masses that would normally collapse in behind his car (creating eddys and other turbulence) are now shunted to the the rear of the drafting vehicle. The drafting vehicle experiences even greater fuel savings than the leader because he is spared the larger frontal resistance that is still the leader's to bear. But, BOTH experience fuel savings due to drafting. Same in cycling, though to a smaller degree. An ornithologist friend who dabbles in physics indicates that roughly the same is true of birds flying "in formation" - all including the leader benefit from the drafting process, the leader just gets less benefit than the rest. Same for fully submerged bodies in water. I can't tell you precisely how this translates to swimming though as there is a huge added variable because swimming is performed at the surface. How turbulence/waves/eddys etc are created and dissapated at the air/water boundary are entirely different than underwater.

Here's an experiment that may answer some of your questions: Go to the bathtub, fill it up with water. Take your 3 hole punch and empty the confetty over the water surface. Put your hand in the water (slowly and carfully, to disturb the surface as little as possible) then pull your hand in a fast liner motion in one direction, as if it is a swimmer going in that direction. Watch what happens to the confetti. Do it again, at variable speeds and variable hand depth and cross section.

One thing is certain: the lead swimmer is NOT "pulling along" the drafting swimmer. The draftee may affect the leaders wake, but as emmett suggested, if anything it might add a fairing effect and actually aid the lead swimmer. Here's a simple experiment we did in a fluid mecanics lab in college. We had two cylinders of equal diameter one directly in front of the other in a wind tunnel. We measured the drag on each cylinder as the trailing cylinder was moved further back. Basically the trailing cylinder got the best draft benefit very close to the the front cylinder (maybe 3D or so?), but I don't think the lead cylinder's drag was affected much if at all.

Originally posted by emmett I don't think that what happens with the confetti relates in any significant way to the drafting effects we are talking about. It just shows where the tail eddys and turbulence and, perhaps how it moves. Actually that is exactly what we are looking for. It tells us that a swimmer passing through the quiescent water will accelerate that water in the direction he/she is swimming. All it tells us is it's possible to draft, though. It tells us some of that swimmer's (or hand's) energy has been transferred into moving the water forward. It doesn't really help answer the question of whether the lead swimmer is helped or hindered by a drafting swimmer, though.

Originally posted by geochuck I will gladly share some of my experiences, and some of the stuff about my older brother Tom and some other guys that swam in my time, like Dennis Matuch the Chicago cop, Cliff Lumsden. George Young, the Black Shark Earnest Verkotter, the hunan windmill Gambi the Italian who stroked 100 strokes a minute from an earlier time. You do understand that Canada was where Marathon races started and some of the greatest marathon swimmers came from. George My understanding is that the lead goose tires not because he is "pulling" the others along, but because the others are benefitting from the draft and he is not, so he tires more quickly.