5 ms·

The roller ship was not an effective way to cross the high seas

109 points by Stratoscope 3y ago

helsinkiandrew 3y ago
Reminded me of the 19th century Russian circular ironclads: https://en.wikipedia.org/wiki/Russian_monitor_Novgorod https://en.wikipedia.org/wiki/Russian_monitor_Novgorod
- 082349872349872 3y ago
  If someone does a steampunk version of Star Wars, that'd be the Falcon design.
mojomark 3y ago
"The general hope was that the roller ship would slash travel times by virtue of its low-drag design. Sadly, an attempt to cross the English Channel in 1897 revealed that the roller design had one unforeseen drawback. In the water, the rollers tended to drag a great deal of water up with them as they rotated." Super fun. I'm a marine engineer and design vessels. I've seen a lot of whacky designs over the years and never encountered this one! Apparently, from the above quote, the culprit for increased drag was skin friction (in this case, that meant water clinging to the surface of the rollers and being lifted out of the water - kind of like the reverse effect of a Tesla turbine which exploits skin friction between moving air and a stack of rigid discs on a rotor). That would certainly cause propulsive inefficiencies. However, from my view, the primary source of drag here are the "hollows" between the rotor discs. If you were to look at a plan (top) view of the vessel as it moves through the water you would find significant water pressure gradients between (at the aft and fore end of) each wheel. When you have multiple wheels in series, you have oscilating high and low pressure zones along the length of the waterline. That's a tremendous amount of energy lost to water turbulance. When you look plan views of hydrodynamic hullforms at the waterline (whether monohull, or multihulls like catamaran/trimarin/SWATH) or even aircraft foil shapes, you don't see "wavy" form lines for this very reason. I will say that these inventers were encroaching on the SWATH hull shape. The author states that this roller disc hull would not be stable due to the high CG. However, SWATH hulls are known for their stability in high sea states.
- LorenPechtel 3y ago
  So many things are obvious once pointed out. I never would have thought of pressure gradients but once you did it's obviously a very uneven surface and you don't do that in anything contending with a lot of drag. How do you see this as a SWATH? This is a catamaran that combines buoyancy and propulsion. I do agree it has a high center of gravity, but that's a relative term--what counts is the ratio of height to width. And a catamaran or SWATH has a much wider base than a typical ship. Wikipedia says SWATH ships require complex control systems--why? Yes, they're very load sensitive because the small contact at the surface means a lot of vertical movement to compensate for weight changes, but couldn't that simply be handled with some pumps and tanks? Make the ship always weigh X--take on water or pump it out as needed to maintain that X.
  - usrusr 3y ago
    I'm not a marine anything, but I'd assume that the control system Wikipedia mentions are ballast tanks that need to reflect any change in load, load distribution and even wind load I'd guess. Sinking a little deeper won't do much to compensate increased load because the small surface area means little change in displacement per change in vertical position. Active trimming pumps.
    - LorenPechtel 3y ago
      Yes, but how is that all that complex by modern standards? Dealing with known weight, simply pump the right number of gallons. If your ship can change weight rapidly you might need some fairly big pumps. (I'm thinking of a warship--VLS equipped ships can throw an awful lot of weight into the sky awfully quickly. But on the flip side you can dispense with a whole bunch of stuff meant to deal with the missile exhaust--your VLS tubes go all the way through the ship, when the missile lights it simply blows a panel open on the bottom of the cell and the exhaust slams into the ocean. And it's a safety advantage to be able to jettison a missile without having to launch it or rig a crane.)
      - usrusr 3y ago
cpeterso 3y ago
“In 2016 a Florida man attempted to run from Boca Raton, FL to Bermuda in a home-made, inflatable plastic bubble. Reza Baluchi had been warned by the Coast Guard that any efforts to attempt his journey would be futile and result in severe legal and financial retribution. However, Reza’s convictions and ambition left him undeterred by such threats - he’d been waiting his whole life to do this and nothing was going to stop him. This is the story of that fateful journey as told by the man who attempted it.” https://youtu.be/da6_LjiIzXk https://youtu.be/da6_LjiIzXk
- ricardobeat 3y ago
  That video is so frustrating. The coast guard complains the “rescue” cost $144k, but nobody called for it, and then they sink $120k of private equipment for no good reason. What a waste of resources. No difference from people who cross the atlantic alone in a kayak but they don’t get forcibly rescued.
  - rokkitmensch 3y ago
    Typical USG "because we can, and nobody can stop us, therefore we're correct".
- senkora 3y ago
  It seems to me like, if he were to have tried to do the voyage accompanied by a dedicated support boat, then the Coast Guard probably would have let him do it. On his first trip, the Coast Guard intercepted him, but eventually let him continue, but then a few days later he had to be rescued. On his second trip, they were much less lenient and forcibly removed him from the bubble. So it sounds to me like the Coast Guard didn’t think he had planned well enough to do what he was trying to do safely, and they were probably right. If he had instead done a series of progressively longer trips accompanied by a support ship ready to rescue him, and then planned to do the trip to Bermuda with a support ship, then he may have been able to convince the Coast Guard to authorize him to do the voyage.
Animats 3y ago
"Damnation Alley" (1977) had the "Landmaster" [1], a large ATV with a roller ship mode. But that was an amphibious vehicle with some river crossing capability, not a ship. There are amphibious monster trucks. Here's a Russian one.[2] No props, just ridged tires. They're not great watercraft, but if you are crossing frozen ground and break through the ice over a lake, they can grind across the water and up onto hard ground. [1] https://youtu.be/26n3RsXNyKE?t=392 https://youtu.be/26n3RsXNyKE?t=392 [2] https://www.youtube.com/watch?v=3j7n00Xx38o&t=104s https://www.youtube.com/watch?v=3j7n00Xx38o&t=104s
- ChrisMarshallNY 3y ago
  Argh. I just got PTSD from that reference. Damnation Alley was Plan 9 From Outer Space-level bad.
- bryanlarsen 3y ago
  SHERP is a Ukrainian brand that used to have production facilities in Russia.
  - user32489318 3y ago
    Did research on this company quite a while ago, so this may not be fully accurate now. Back then, it was a Saint Petersburg based. In my opinion, most likely state subsidized. On its own SHERP, is just a commercial substitute for homemade vehicles popular in the Northern Russia going back to ‘60s. The company model hinges on a patent of one or more critical components (wheels, drivetrain,..). That model failed for its predecessors, see link below. It is hard to google, but there a bunch of research papers and open source designs (from 80s, 90s) for all kinds of wacky 3, 4, 6-wheelers. The last patents related to these expired in early 00. Newer patents are all from the SHERP guys. The older patents are from a bunch of other companies that failed before Sherp. For instance, one below was made by SMZ in ‘94, (sub)contractor for the military that produces parts for nuclear submarines and what not. https://pnevmohod.ru/forum/index.php?topic=3956.2180 https://pnevmohod.ru/forum/index.php?topic=3956.2180 (Now nicknamed Elon’s cyber truck)
pfdietz 3y ago
Drachinifel on these: https://www.youtube.com/watch?v=qNLf0yt0IHo&t=1559s https://www.youtube.com/watch?v=qNLf0yt0IHo&t=1559s
jbm 3y ago
> Rather than turning quickly, the rollers labored and the craft could barely break a dozen miles an hour according to a contemporary account. Even for the late 19th century, that was slow This reminds me of a lot of my failed efforts to refactor code.
yalue 3y ago
Heh, so it's an 1897 version of what this guy on youtube attempted with a monster truck with mild success: https://www.youtube.com/watch?v=ohxGA7fpfu0 https://www.youtube.com/watch?v=ohxGA7fpfu0 (warning: extremely redneck)
cratermoon 3y ago
Oh, so the self-driving car of the late 19th century
RecycledEle 3y ago
I know the texture of the wheels on a roller ship (or the hull on a traditional ship) determines its drag coefficient. Are there materials that let us change that on the fly? For example, can we apply a magnet to the back of some material to change its surface to increase or decrease its coefficient of drag?

109 points by Stratoscope 3y ago

Reminded me of the 19th century Russian circular ironclads: https://en.wikipedia.org/wiki/Russian_monitor_Novgorod https://en.wikipedia.org/wiki/Russian_monitor_Novgorod

082349872349872 3y ago
If someone does a steampunk version of Star Wars, that'd be the Falcon design.

mojomark 3y ago

"The general hope was that the roller ship would slash travel times by virtue of its low-drag design. Sadly, an attempt to cross the English Channel in 1897 revealed that the roller design had one unforeseen drawback. In the water, the rollers tended to drag a great deal of water up with them as they rotated." Super fun. I'm a marine engineer and design vessels. I've seen a lot of whacky designs over the years and never encountered this one! Apparently, from the above quote, the culprit for increased drag was skin friction (in this case, that meant water clinging to the surface of the rollers and being lifted out of the water - kind of like the reverse effect of a Tesla turbine which exploits skin friction between moving air and a stack of rigid discs on a rotor). That would certainly cause propulsive inefficiencies. However, from my view, the primary source of drag here are the "hollows" between the rotor discs. If you were to look at a plan (top) view of the vessel as it moves through the water you would find significant water pressure gradients between (at the aft and fore end of) each wheel. When you have multiple wheels in series, you have oscilating high and low pressure zones along the length of the waterline. That's a tremendous amount of energy lost to water turbulance. When you look plan views of hydrodynamic hullforms at the waterline (whether monohull, or multihulls like catamaran/trimarin/SWATH) or even aircraft foil shapes, you don't see "wavy" form lines for this very reason. I will say that these inventers were encroaching on the SWATH hull shape. The author states that this roller disc hull would not be stable due to the high CG. However, SWATH hulls are known for their stability in high sea states.

LorenPechtel 3y ago
So many things are obvious once pointed out. I never would have thought of pressure gradients but once you did it's obviously a very uneven surface and you don't do that in anything contending with a lot of drag. How do you see this as a SWATH? This is a catamaran that combines buoyancy and propulsion. I do agree it has a high center of gravity, but that's a relative term--what counts is the ratio of height to width. And a catamaran or SWATH has a much wider base than a typical ship. Wikipedia says SWATH ships require complex control systems--why? Yes, they're very load sensitive because the small contact at the surface means a lot of vertical movement to compensate for weight changes, but couldn't that simply be handled with some pumps and tanks? Make the ship always weigh X--take on water or pump it out as needed to maintain that X.
- usrusr 3y ago
  I'm not a marine anything, but I'd assume that the control system Wikipedia mentions are ballast tanks that need to reflect any change in load, load distribution and even wind load I'd guess. Sinking a little deeper won't do much to compensate increased load because the small surface area means little change in displacement per change in vertical position. Active trimming pumps.
  - LorenPechtel 3y ago
    Yes, but how is that all that complex by modern standards? Dealing with known weight, simply pump the right number of gallons. If your ship can change weight rapidly you might need some fairly big pumps. (I'm thinking of a warship--VLS equipped ships can throw an awful lot of weight into the sky awfully quickly. But on the flip side you can dispense with a whole bunch of stuff meant to deal with the missile exhaust--your VLS tubes go all the way through the ship, when the missile lights it simply blows a panel open on the bottom of the cell and the exhaust slams into the ocean. And it's a safety advantage to be able to jettison a missile without having to launch it or rig a crane.)
    - usrusr 3y ago

cpeterso 3y ago

“In 2016 a Florida man attempted to run from Boca Raton, FL to Bermuda in a home-made, inflatable plastic bubble. Reza Baluchi had been warned by the Coast Guard that any efforts to attempt his journey would be futile and result in severe legal and financial retribution. However, Reza’s convictions and ambition left him undeterred by such threats - he’d been waiting his whole life to do this and nothing was going to stop him. This is the story of that fateful journey as told by the man who attempted it.” https://youtu.be/da6_LjiIzXk https://youtu.be/da6_LjiIzXk

ricardobeat 3y ago
That video is so frustrating. The coast guard complains the “rescue” cost $144k, but nobody called for it, and then they sink $120k of private equipment for no good reason. What a waste of resources. No difference from people who cross the atlantic alone in a kayak but they don’t get forcibly rescued.
- rokkitmensch 3y ago
  Typical USG "because we can, and nobody can stop us, therefore we're correct".
senkora 3y ago
It seems to me like, if he were to have tried to do the voyage accompanied by a dedicated support boat, then the Coast Guard probably would have let him do it. On his first trip, the Coast Guard intercepted him, but eventually let him continue, but then a few days later he had to be rescued. On his second trip, they were much less lenient and forcibly removed him from the bubble. So it sounds to me like the Coast Guard didn’t think he had planned well enough to do what he was trying to do safely, and they were probably right. If he had instead done a series of progressively longer trips accompanied by a support ship ready to rescue him, and then planned to do the trip to Bermuda with a support ship, then he may have been able to convince the Coast Guard to authorize him to do the voyage.

Animats 3y ago

"Damnation Alley" (1977) had the "Landmaster" [1], a large ATV with a roller ship mode. But that was an amphibious vehicle with some river crossing capability, not a ship. There are amphibious monster trucks. Here's a Russian one.[2] No props, just ridged tires. They're not great watercraft, but if you are crossing frozen ground and break through the ice over a lake, they can grind across the water and up onto hard ground. [1] https://youtu.be/26n3RsXNyKE?t=392 https://youtu.be/26n3RsXNyKE?t=392 [2] https://www.youtube.com/watch?v=3j7n00Xx38o&t=104s https://www.youtube.com/watch?v=3j7n00Xx38o&t=104s

ChrisMarshallNY 3y ago
Argh. I just got PTSD from that reference. Damnation Alley was Plan 9 From Outer Space-level bad.
bryanlarsen 3y ago
SHERP is a Ukrainian brand that used to have production facilities in Russia.
- user32489318 3y ago
  Did research on this company quite a while ago, so this may not be fully accurate now. Back then, it was a Saint Petersburg based. In my opinion, most likely state subsidized. On its own SHERP, is just a commercial substitute for homemade vehicles popular in the Northern Russia going back to ‘60s. The company model hinges on a patent of one or more critical components (wheels, drivetrain,..). That model failed for its predecessors, see link below. It is hard to google, but there a bunch of research papers and open source designs (from 80s, 90s) for all kinds of wacky 3, 4, 6-wheelers. The last patents related to these expired in early 00. Newer patents are all from the SHERP guys. The older patents are from a bunch of other companies that failed before Sherp. For instance, one below was made by SMZ in ‘94, (sub)contractor for the military that produces parts for nuclear submarines and what not. https://pnevmohod.ru/forum/index.php?topic=3956.2180 https://pnevmohod.ru/forum/index.php?topic=3956.2180 (Now nicknamed Elon’s cyber truck)

pfdietz 3y ago

Drachinifel on these: https://www.youtube.com/watch?v=qNLf0yt0IHo&t=1559s https://www.youtube.com/watch?v=qNLf0yt0IHo&t=1559s

jbm 3y ago

> Rather than turning quickly, the rollers labored and the craft could barely break a dozen miles an hour according to a contemporary account. Even for the late 19th century, that was slow This reminds me of a lot of my failed efforts to refactor code.

yalue 3y ago

Heh, so it's an 1897 version of what this guy on youtube attempted with a monster truck with mild success: https://www.youtube.com/watch?v=ohxGA7fpfu0 https://www.youtube.com/watch?v=ohxGA7fpfu0 (warning: extremely redneck)

cratermoon 3y ago

Oh, so the self-driving car of the late 19th century

RecycledEle 3y ago

I know the texture of the wheels on a roller ship (or the hull on a traditional ship) determines its drag coefficient. Are there materials that let us change that on the fly? For example, can we apply a magnet to the back of some material to change its surface to increase or decrease its coefficient of drag?