BS: Trump boat parade - science of it

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 30 Sep 20 - 01:19 PM

That's interesting. I've never heard of a surfer riding a wake before. I'd love to be in Miami watching them right now.

Subject: RE: BS: Trump boat parade - science of it
From: gillymor
Date: 28 Sep 20 - 12:02 PM

When I lived in Miami we used to go down to Crawdaddy's on Government Cut on Saturday evenings to sip Daiquiris and watch the cruise ships depart for the Caribbean. Surfers would congregate in the pass and ride the ship's wakes almost all the way to the sea wall. Woe to the tourist who sat at a table too close to the water, they were in for a good drenching.

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 28 Sep 20 - 11:30 AM

Donuel, I got out my atlas and reviewed Lake Michigan geography. Four states share it.

If we pretend that the long, north-south loop of Lake Michigan is a zucchini, then Illinois and Indiana share the blossom end. Wisconsin and Michigan share the long sides, and Michigan's Upper Peninsula gets the stem end.

The DH pointed out that the image of Wisconsin (say) that we have in our minds is a map of the land, but the actual state line between Wisconsin and lower Michigan is in the middle of the lake.

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 25 Sep 20 - 08:30 PM

Quite likely correct. If you watch surfers, they ride a relatively low wave in until it breaks near shore.

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 25 Sep 20 - 05:44 PM

My dear husband tells me that one can buy small gizmos to put on a boat and make it detectable to radar. That sounds like a good idea too.

I want to add that I admire the courage of the leader of the kayakers, who set out rescuing people even though he had a dislocated shoulder. Both my mother and my sister have suffered dislocated shoulders from falls, and they tell me the pain is simply terrible.

He also says that a factor in the five sunk boats in the Lake Travis parade is that no doubt many of the boats were in shallow water. Waves that start in deep water (the original river channel) and go into shallow water (the drowned floodplain) get taller as they approach shore. Since Lake Travis is a reservoir created from a broad river valley, it probably has lots of shallow water.

Good for you for reporting the hostile boater to the Coasties.

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 24 Sep 20 - 11:08 PM

It might. Personally, I would want the strobe on at all times, along with a flag. That way you have better and night visibility. Also, carry a radio set to scan channels 13 and 16.
One time, I was coxing a youth group rowing around Manhatten. I spotted a power boat coming up Buttermilk Channel [between Governor's Island and Brooklyn] and attempted to hail him as he was headed directly toward us. I made sure we were on 16 and called several tunes [The Coast Guard and Marine Police monitor 16.] Finally, I called him and said that if he got any closer, we would board him with knives in our teeth. He sheered off. We reported his registration number and the name on his transom to the Coasties.

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 24 Sep 20 - 05:24 PM

Thanks for the link, ebarnacle. That was an interesting article. I didn't know people kayak in New York harbor.

Would it help for a kayak to have one of those brilliant flashing white lights that I see on bicycles? They need only be turned on when a big boat is near.

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 24 Sep 20 - 05:13 PM

Close, Donuel. A long-term Wisconsinite.

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 23 Sep 20 - 03:04 PM

Getting closer to the original concept of big and small boats mixing it up, here's a report about an incident that did not go well. I was part of the follow-up conference.

https://paddlingmag.com/safer-paddling/what-kayakers-can-learn-from-the-new-york-ferry-collision/?utm_source=Paddling+Magazine&u

Subject: RE: BS: Trump boat parade - science of it
From: Donuel
Date: 23 Sep 20 - 12:59 PM

You're a Michi gander!

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 23 Sep 20 - 12:43 AM

That's funny, EBarnacle. He didn't seem incoherant to me, but then I'm from Wisconsin too. And saints forfend he should be against drinking on the boat; what he was against was throwing the empty can into the lake.

That body of sparkling blue water has got to be Lake Michigan. Makes me homesick.

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 22 Sep 20 - 09:46 PM

While the Neutrinos are very proud of their "recycled" rafts, by their very nature, they are a source of polluting microplastics. Plastics, as a rule, break down from solar exposure. Styrofoam beads separate themselves for the larger pieces. All of the materials would be better off properly recycled. Even the styrofoam can now be recycled, though it rarely is.
Son of Town Hall and its relatives are simply ways for people to live on the cheap outside of taxable zones. The Neutrinos, while in NYC, lived next to the City. even though they were within the territorial limits of the City and the State of New York, they were very much like the Bundy family in their refusal to accept government authority.
The reason they began their trip was that the Hudson River Park Trust refused to allow them to tie up there any longer.
The most recent entry in their web site said that the French government was threatening to break it up. That was over a decade ago.

Subject: RE: BS: Trump boat parade - science of it
From: DaveRo
Date: 22 Sep 20 - 02:59 AM

First Raft Made of Scrap to Cross the North Atlantic Ocean

'Make of scrap' - but pretty seaworthy.

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 21 Sep 20 - 09:40 PM

A cartoon appeared in WoodenBoat magazine, January/February, 1999, page 14 as a comment on the Floating Neutrinos' completion of a transatlantic trip aboard Son of Town Hall. I helped launch it and I really though the Coast Guard would seize the "boat."
If you Google Son of Town Hall, you should be able to bring up a story about it.

The cartoon shows a buch of ragged "sailors" aboard a hollow log with an angel overhead and i captioned ""Chalk up another one to St. Imbecile, saint of informal ocean crossing." Somehow, it just seems appropriate.
[I had hoped to copy and paste the cartoon but it didn't work out.]

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 19 Sep 20 - 02:09 PM

50, just because!

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 19 Sep 20 - 01:43 PM

He seemed rather incoherent except on the subject of not drinking alcohol while afloat.

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 18 Sep 20 - 03:59 PM

I'm sorry to hear that. It must have been terrifying.
=================================
Here's a link to a YouTube video that will give you guys a bunch of boat knowledge you haven't heard before:

next to the leeches

Subject: RE: BS: Trump boat parade - science of it
From: Donuel
Date: 18 Sep 20 - 03:29 PM

Turbulence looks innocent from above. I got sucked down to the bottom of a lake that formed a vortex.

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 18 Sep 20 - 01:23 PM

Thanks for the link, Donuel. I enjoyed the dolphin.

Whenever I cross the Missouri River, I get to observe its turbulence. The water forms bunches, and it looks as if people have cut brown bunches of broccoli crosswise and packed them into the river. (This is the appearance of jets of water going up and down, rather that going downvalley, the way they should.) The Corps of Engineers has made the River narrower and faster than it used to be, so there really isn't room for all that water in its course.

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 17 Sep 20 - 11:16 PM

Good article. I shared it with the head of the National weather service for thus region. The same sorts of vortices can be seen in tornados and cyclonic storms.

Subject: RE: BS: Trump boat parade - science of it
From: Donuel
Date: 17 Sep 20 - 07:52 PM

Fluid dynamics beyond boats https://www.quantamagazine.org/an-unexpected-twist-lights-up-the-secrets-of-turbulence-20200903/

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 15 Sep 20 - 02:34 PM

All those people would have been fine except for one thing - because of the power of social media to bring people together, there were too many boats in the same place at the same time. This is not a problem which will be dealt with by any test or course.

The Texans seemed to be going too fast, but the people on the St Croix were going slower and still had problems with their wakes.

Subject: RE: BS: Trump boat parade - science of it
From: Jon Freeman
Date: 14 Sep 20 - 09:16 AM

It can get worse than that. I'm a bit young but I rember and went to see the Rethi Mueller (a quarry stone carrying boat) run ashore in Penmaenmawr. I've no idea as regards the truth but there were local rumours that say the captain was in bed with a local lady when it happened.

Anyway, to get more serious. I guess that living years in N Wales taught me that each year someone(s) going have a fatal fall from a mountain, someone may find the shock of diving into an "ice cold" lake on a hot day too much for their system, some will get into trouble in the sea.

Mum often looks in on the (I think) Llanberis and Ogwen Mountain Rescue sites and they have countless tales of clowns (usually) getting rescued.

I think the message is boating, hill walking or whatever, do some research first and don't try to be smarter than the safety advice given.

Subject: RE: BS: Trump boat parade - science of it
From: Donuel
Date: 14 Sep 20 - 07:46 AM

Well put. Plus alcohol is practicly a given.

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 13 Sep 20 - 03:45 PM

There is, regrettably no operator's license in most states. Both New York and New Jersey have minimal requirement for operator's endorsements [a class based on the US Power Squadron book, Piloting, Seamanship and Small Boat Handling, as it used to be called]. There is not functional exam. You can just hop into your [un] guided missile and power away.
PWC [jetski] users have a similar requirement but I believe the exam is slightly different. I have seen more than a few of them not wearing life jackets. Also, no one seems to have explained that the damn things have no brakes and no control when the thrust is off.

Subject: RE: BS: Trump boat parade - science of it
From: Donuel
Date: 13 Sep 20 - 01:55 PM

boats don't drive boats, people do. Look for the best answer there

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 13 Sep 20 - 01:48 PM

The experienced sailors here don't think that hooligans were required to make the wakes from all those boats go berserk. This video shows boats travelling in an orderly manner, but with only one thing wrong - they are going too fast.

I doubt if many of them claim to be real sailors. They are family people who take their boat on a big reservoir, and they don't go out when it's raining. That doesn't make them wicked people. It does make the people who organized the rally stupid people, however.

Subject: RE: BS: Trump boat parade - science of it
From: Penny S.
Date: 13 Sep 20 - 03:17 AM

Subject: RE: BS: Trump boat parade - science of it
From: Backwoodsman
Date: 13 Sep 20 - 12:50 AM

”It has been said that there are old sailors and there are bold silors but they are not usually the same.
Anyone who does not respect and fear the waters at some level is fool.
The laws of physics don't care who you are or respect your politics.“

Absolutely correct, EB. Real sailors know this. Most of those people behaving like hooligans in their expensive toys at that ‘boat-rally’ appeared not to qualify. And real sailors know what happens when boats are mis-handled at close quarters with other boats in confined waters. What happened wasn’t the fault of the lake, it wasn’t the fault of the boats - it was the fault of the morons driving them.

I don’t know how it is in the US, but I do have to wonder if any kind of formal training qualification is required before someone is permitted to jump into a boat and drive it away - something akin to a nautical version of the automobile test? If not, why not?

Subject: RE: BS: Trump boat parade - science of it
From: Sandra in Sydney
Date: 12 Sep 20 - 08:05 PM

well said, E

I recently picked up a copy of a Darwin Awards book & had a great time reading it.

sandra

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 12 Sep 20 - 07:17 PM

A couple of issues:
The Darwin awards were created for people who remove themselves from the gene pool.
It has been said that there are old sailors and there are bold silors but they are not usually the same.
Anyone who does not respect and fear the waters at some level is fool.
The laws of physics don't care who you are or respect your politics.

Subject: RE: BS: Trump boat parade - science of it
From: Backwoodsman
Date: 12 Sep 20 - 02:37 PM

I know the feeling, Gilly! ;-)

Subject: RE: BS: Trump boat parade - science of it
From: gillymor
Date: 12 Sep 20 - 01:50 PM

It's getting to me, BW.

Subject: RE: BS: Trump boat parade - science of it
From: Backwoodsman
Date: 12 Sep 20 - 01:45 PM

Gilly, you were spot-on until the ‘all drown’ comment.

Subject: RE: BS: Trump boat parade - science of it
From: gillymor
Date: 12 Sep 20 - 01:41 PM

You're quite right. That was a knee jerk response to this thread and I shouldn't have posted it.

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 12 Sep 20 - 12:25 PM

That's sick. We don't wish death for people just because they're naive and they've been artfully lied to.

Subject: RE: BS: Trump boat parade - science of it
From: gillymor
Date: 12 Sep 20 - 05:54 AM

These idiots were out in the water in their booze barges in support of the most incompetent, corrupt and amoral public figure in our history, the only tragedy here is that they all didn't drown.

Subject: RE: BS: Trump boat parade - science of it
From: Backwoodsman
Date: 12 Sep 20 - 03:50 AM

”I think we’re done here. The boats sank or hit the rocks because there were too many of them too close together, going too fast.”

Yep, I agree. However you slice and dice it, it was down to humans behaving like idiots. Boats, like automobiles, are death-traps in the wrong hands.

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 12 Sep 20 - 01:32 AM

Dave, I don't know about boat instruments. Our boat is a rowboat, and we take it on quiet rivers, to birdwatch.

I think the parade in Texas was called together by people who didn't know enough about boats, and the Trump supporters in the parade found themselves in a situation they could not control. The boat being overwhelmed in the New York Times photograph is a houseboat, intended for toddling along in quiet waters. I'm sure the owners didn't visualize themselves surrounded by turbulent wakes and fast boats which are way too close.

I am reminded of a party that some teenagers posted on Facebook in my city. Four hundred people showed up! The hosts were swamped, didn't know most of the people, and a serious number of Covid 19 cases could be traced to the event. As with the boat parade, when you put an event on social media, you lose control.

I wondered whether boat parades are common, and if anybody has developed rules for running a safe parade. I learned that there are quite a few boat parades in Florida at Christmastime, but I didn't find anything on how they are organized.

I think we're done here. The boats sank or hit the rocks because there were too many of them too close together, going too fast.

Subject: RE: BS: Trump boat parade - science of it
From: DaveRo
Date: 11 Sep 20 - 01:02 PM

This is informative: Those boats in Texas paraded at the wrong speed

So 5 miles per hour would have been ideal, just fast enough to maintain manoeuvrability. That’s in fact what the Slow No Wake navigational cans in harbours often dictate. At 10 miles per hour, you’re not planing yet. But you are closer to maximum drag, and therefore maximum wake. The Lake Travis boat parade was too slow to plane. But it was fast enough to kick up waves.

(Do US boats' speed instruments actually use mph?)

I was amused by the political points:

• Elite Democrats go sailing.
• Elite Republicans go fishing.

Subject: RE: BS: Trump boat parade - science of it
From: Backwoodsman
Date: 11 Sep 20 - 03:55 AM

You can make excuses until you’re blue in the face, but the simple fact is that people were misbehaving in a dangerous environment. Anyone watching that video, who has expertise in seamanship and boat-handling, would tell you that it was a disaster waiting to happen.

Too many boats in too crowded a space, driven by too many over-excited (and possibly alcoholically-over-refreshed) people with too little regard to proper seamanship and boat-handling skills. End of.

Subject: RE: BS: Trump boat parade - science of it
From: DaveRo
Date: 11 Sep 20 - 03:00 AM

I only watched the first few minutes, but I'd say that the majority are not going faster than 10mph (I assume the speed was supposed to be 8 knots), or not much. Some of the bigger boats look like commercial trip boats and I doubt if their masters would compromise their licences and insurance by exceeding local regulations.

But there are a few boats which certainly are exceeding that, and some going at planing speed, which creates a bigger wake close by. But they're all too close together, and the little boats are too near the big ones.

Imagine somebody in one of those little motor boats. They probably use it to go out fishing at the weekend, and rarely motor at more than 4 knots. They're being pushed along by the bigger boats - and their enthusiam. There's water coming over from breaking wakes. They'd like to slow down...

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 10 Sep 20 - 02:37 PM

You're right. I saw a video about a Trump parade on the St Croix River (upstream part of the Mississippi), and an observer said it created waves 4-5 feet high. A docked boat sank. In the video, the boats seem to be moving very slowly, but a resident complained of boaters not following boating laws and ettiquet. (sp)

Here's a video of part of the parade on Lake Travis.

https://www.youtube.com/watch?v=7py3HRqnDDw

It seems to me that the boats are going too fast, are too close together, and some of them have too little freeboard. Do you think they are going the prescribed 10 miles per hour? I don't see anybody hot-dogging.

Those boats are going so fast that I thought the video must have been speeded up, but then I saw people on land, and they were moving normally, so it was not speeded up.

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 09 Sep 20 - 09:17 PM

Even if the boats were all travelling in the same direction, the wakes would "flare" out from the direction of travel. After the point of intersection the water would be "confused" and difficult for small boats to deal with, especially if the operators were not skilled in handling what, for them, would be unusual conditions.
the issue is still operator competence as much as is is water conditions.

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 09 Sep 20 - 12:57 PM

I think DaveRo has pointed the way to the physics of what happened: boats were travelling at more-or-less right angles to one another, and when the ridge of one wave met the ridge of another, the water piled up doubly and overwhelmed the small boats. Add to this the notion that one won't need a life jacket on a nice, slow ride, and there's trouble afoot.

I'm reminded of a disaster some years ago when a rumor started that tickets would not be collected for a big football match in England. A huge crowd formed, pressed against steel fences, and people were crushed to death. The moral is that when many people decide to be naughty, naughtiness can lead to tragedy.

With the boat rally, nobody knows how many boats were there or how many were big or small. But with all those boats close together, when some people decided to go perpendicular to the prescribed path (probably at high speed), they created dangerous, choppy conditions that sank five boats, endangered others, and caused an unknown number of boats to hit rocks.

I'm glad nobody was hurt or drowned, but I'm sure those who needed to be rescued are not sleeping peacefully yet.

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 09 Sep 20 - 12:35 PM

I'd never heard of the hundred-foot rule, so I googled it and found a quotation:

"It's called the 100 foot rule. If you're within 100 feet of another object -- another watercraft, a dock, a swimmer -- you're supposed to slow down to idle speed. If people did that almost all these accidents could be avoided." -Lt.

The source is the Forsyth County Sheriff's Office, wherever that may be.

Subject: RE: BS: Trump boat parade - science of it
From: DaveRo
Date: 09 Sep 20 - 11:45 AM

EB: I started that post before seeing yours.

Subject: RE: BS: Trump boat parade - science of it
From: DaveRo
Date: 09 Sep 20 - 11:42 AM

However, I think the relevant physics here is the stability of floating objects (centre of flotation, righting moments, etc.) and wave dynamics.

Take home message: small boats and big wakes don't mix.

I googled and found that the '100 foot rule' is a thing in the US.

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 09 Sep 20 - 11:37 AM

As we are talking about moving objects, we are discussing kinetic energy. If you want to raise the question of acceleration, water displaced from 0 velocity into a continuous wave at, for example, 10 knots can create a substantial and damaging wake. In this case, acceleration quickly reaches maximum velocity from zero. When you have several large boats in proximity, the wakes become a confused pattern and, thus, dangerous because they are hard to respond to.

If you ask any small boat operator, the best way to avoid wake damage is to point the boat at about 60 to 90 degrees to the wave. Parallel to the wave risks being overwhelmed. {Small is relative to conditions.]

My personal approach is to approach the wave at about 60 degrees, taking a more gradual angle of attack to the face of the wave.
When I have a crew, the lookouts are instructed to alert me to oncoming wakes and waves.

Subject: RE: BS: Trump boat parade - science of it
From: Doug Chadwick
Date: 09 Sep 20 - 10:14 AM

The force that the book exerts on the table, F = mg where 'm' is the mass of book and 'g' is the acceleration due to gravity.

Mass*velocity does not equal kinetic energy. It is, as said before, momentum. Kinetic energy = ¹/₂mv².

DC

Subject: RE: BS: Trump boat parade - science of it
From: Donuel
Date: 09 Sep 20 - 06:16 AM

Psychology and behavior is often not seen as science/
Does anyone here actually calculate fluid dynamics? I can't.

Subject: RE: BS: Trump boat parade - science of it
From: Nigel Parsons
Date: 09 Sep 20 - 05:26 AM

I know it's being picky, but force is equal to mass times acceleration Not strictly true. Stationary objects can exert a force on other objects. A book on a table exerts a force on the table (resisted by an equal and opposite force by the table on the book). This might involve the potential for acceleration (due to gravity), but there is no acceleration in play.


Mass*velocity = kinetic energy


I accept I may have made errors in the above as well. A-level physics was 48 years ago.

Subject: RE: BS: Trump boat parade - science of it
From: Doug Chadwick
Date: 09 Sep 20 - 04:29 AM

As basic physics says says, force is equal to mass times velocity, .....

PEDANT ALERT
I know it's being picky, but force is equal to mass times acceleration. Mass times velocity is momentum. If we are talking about the science of it, it's best to get it right.

DC

Subject: RE: BS: Trump boat parade - science of it
From: EBarnacle
Date: 09 Sep 20 - 12:18 AM

I saw an article [parody?] today that their insurance claims are being denied. I believe there is a "safe operation" clause in most policies. It would be the same sort of clause that requires operators of all vessels to maintain a good lookout at all times.

As one who has spent a lot of time on the water, I can testify that large boats, even operated at reasonable speeds, in confined waters create very large wakes which can be destructive to both structures and other boats.

I would be very surprised if none of the small boat owners take advantage of the principle that a boat owner is held responsible for any damage his wake does.

As basic physics says says, force is equal to mass times velocity, especially if, as in this case, the boats were operating at what is called displacement speed.

We have a situation here with people of varying skill levels all operating in close proximity to each other. Looking at videos of the event, I noted that most of them were not wearing life jackets [required by the Coast Guard in these circumstances, especially in smaller boats] or masks.

The indications are that there were no lives lost. Will any of them learn any lessons in safe boating from this? I doubt it.

https://www.dailykos.com/stories/2020/9/6/1975496/-Trump-Boaters-Out-Of-Luck-Insurance-Claims-Denied

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 08 Sep 20 - 05:25 PM

Science. We're trying to talk about science.

Subject: RE: BS: Trump boat parade - science of it
From: Donuel
Date: 08 Sep 20 - 11:18 AM

There was probably a show off 'go big or go home' feeling in the air.
If it had a name 'Cowboy Boating' would work.

A vehicle rally will mostly be pick up trucks rolling coal with mufflers with drilled out holes. Anyone with a military vehicle will not be able to resist even if they know they won't go far.

Symbols of violence will be proudly displayed.

YAAH HOOOO

Subject: RE: BS: Trump boat parade - science of it
From: leeneia
Date: 07 Sep 20 - 10:53 PM

Thanks, Dave. I should have considered that. Just because the organizers wanted people to limit their speed doesn't mean they would all do it. I was trying to visualize parallel wakes making such trouble, but I thought that roughly half of them would reinforce each other and half would cancel out.

Hmm. If a circular wake intersects a long wake, that would make high peaks of water, wouldn't it? Then add a wind gust of 15 mph. What do you boaters think?
================
Yes, Joe. The FIB effect.

Subject: RE: BS: Trump boat parade - science of it
From: Bill D
Date: 07 Sep 20 - 09:04 PM

I see they are planning a vehicle rally south of Portland soon... perhaps they read about Texas and will be more careful...

Subject: RE: BS: Trump boat parade - science of it
From: The Sandman
Date: 07 Sep 20 - 04:42 PM

Sinking Ships“Not the waves, not the storms, but often we ourselves sink our ships!”
? Mehmet Murat ildan

Subject: RE: BS: Trump boat parade - science of it
From: Bee-dubya-ell
Date: 07 Sep 20 - 10:55 AM

What the spectacle of pro-Trump boat parades has shown me is just how much support Trump has among the upper-middle-class. Boats are luxury items. Anyone who can afford a cabin cruiser is very well off. If you think Trumpism only appeals to working-class white people whose jobs don't pay as much as they'd like, think again. Those boats belong to people high up the economic ladder.

Subject: RE: BS: Trump boat parade - science of it
From: John MacKenzie
Date: 07 Sep 20 - 05:12 AM

Rednecks with red faces ?

Subject: RE: BS: Trump boat parade - science of it
From: DaveRo
Date: 07 Sep 20 - 02:23 AM

My guess is that some motor boats did not stick to 10mph but were zooming about, possibly in circles, which is what owners of such boats often do. That can generate a big wake, and when the wakes from two or more boats coincide they add up (or subtract) which can create local waves that can easily swamp a small boat. That's what that picture looks like to me.

Subject: RE: BS: Trump boat parade - science of it
From: Joe Offer
Date: 07 Sep 20 - 02:12 AM

During college in the 1960s, I taught boating at a boys' camp in the glacial Kettle Moraine area west of Milwaukee. It was fine during the week, and I felt safe supervising 30 kids in boats on our lake.

But on the weekends, the people from Chicago came up with their speedboats, and the lake was way overcrowded. The waves came up, and there was no way it was safe for kids in canoes and rowboats.

-Joe-

Subject: BS: Trump boat parade - science of it
From: leeneia
Date: 07 Sep 20 - 01:48 AM

On Saturday, Sept 5, someone put a notice on Facebook inviting Trump supporters to parade their boats around Lake Travis in Texas, and such big waves were created that at least four boats sank. Others hit rocks. Here are some factors according to the New York Times:

https://www.nytimes.com/2020/09/05/us/Texas-boat-parade-trump.html

Winds up to 15 mph, boats going 10 miles per hour, boats as big as 60 feet mixed with boats as small as 8 feet, nobody knows how many boats there were because there were so many. Picture shows a family-size boat with a terrified woman on it absolutely engulfed in waves.

Clearly it takes more than a notice on Facebook to organize a safe boat parade. My reaction to the picture was that it would be very dangerous to rescue someone in those waves, but the DH tells me that to rescuers, those waves would be nothing.

I'd like to hear from catters who are experienced with boats. What do you think happened exactly, and how can this be prevented?

As my title says, I'm interested in the science, not the politics.