4 ms·

Ghost: Stealth Attack Hydrofoil Uses Supercavitation

37 points by Hoff 12y ago

idlewords 12y ago
This thing looks like it could really turn the tide in our fight against Cobra.
- ch4s3 12y ago
  Yeah too bad these stealth designs work like ass against WWII era long wave radar. Sure, you can't use long wave for targeting, but something this big sitting so high out of the water seems easy to hit with a shoulder fired rocket. It seems like these super high tech ships and aircraft exist mostly to create jobs in various congressional districts. Then the get sold on the mythology of a cold war nightmare scenario that never happened. oh well. at least we're safe from COBRA.
  - lingben 12y ago
    "Hinges allow the struts to move up and down like wings. While parked, or traveling through shallow waters, they can be extended to the side." Maybe you missed this while scanning the article. This would allow the boat to sit high or low on the water; reminds me of the citroen cx which had high adjustable suspension.
thechut 12y ago
Reminds me of the villains boat in Tomorrow Never Dies [1] 1: http://i.dailymail.co.uk/i/pix/2011/06/19/article-2005464-0CA0FEB500000578-484_634x261.jpg http://i.dailymail.co.uk/i/pix/2011/06/19/article-2005464-0C...
- sandworm101 12y ago
  Which was based on the real Sea Shadow. http://en.wikipedia.org/wiki/Sea_Shadow_%28IX-529%29 http://en.wikipedia.org/wiki/Sea_Shadow_%28IX-529%29
rdtsc 12y ago
Another military device using supercavitation is the Soviet (now Russian) supercavitating torpedo: https://en.wikipedia.org/wiki/VA-111_Shkval https://en.wikipedia.org/wiki/VA-111_Shkval Max speed is 200 knots (230 mph) and it can go for almost 10 miles. That seems almost unreal, an object that size, going at that speed under water.
bazzargh 12y ago
Sancoff began contemplating ways to give back to his country. To him, that meant shifting his focus from medical devices to weaponry. That's a disappointing comment.
rexignis 12y ago
Nothing like this will ever compare with a submersible in terms of "stealth". Who knows, maybe there already exists a supercavitating shallow draft sub for the spooks to use.
sandworm101 12y ago
Not stealth. Far to many flat 90/45* surfaces and corners. Nobody with any understanding of radar was involved in the design of that thing. Not supercavitating. Supercavitation is based on cavitation, not sucking down air from the surface. http://en.wikipedia.org/wiki/Supercavitation http://en.wikipedia.org/wiki/Supercavitation. And the amount of energy needed to create a supercavitation void around those hulls ... The Shkval is essentially an underwater rocket and it still uses exhaust gases to top up the bubble in which it flies (see the little holes near the nose) http://en.wikipedia.org/wiki/VA-111_Shkval http://en.wikipedia.org/wiki/VA-111_Shkval. Not a hydrofoil. No foils. It looks to be a SWATH hull (Small Waterplane Area Twin Hull) another great Canadian invention. http://en.wikipedia.org/wiki/Small-waterplane-area_twin_hull http://en.wikipedia.org/wiki/Small-waterplane-area_twin_hull Who did this guy know at Businessweek to get this sales pitched turned into an "article"?
- tectec 12y ago
  It also reminds me of this Canadian invention: http://en.wikipedia.org/wiki/HMCS_Bras_d'Or_(FHE_400) http://en.wikipedia.org/wiki/HMCS_Bras_d'Or_(FHE_400)
  - sandworm101 12y ago
    Ya, but that ship was an actual hydrofoil. The foils act like wings to generate lift from movement. The thing in the OP uses movable pontoons, buoyancy, to haul itself up regardless of speed. Note also that real hydrofoils angle their foils in parallel to the hull. It's essentially a dihedral effect like that of an airplane. As the ship lists one way, the foil on the downward side pushes more directly upwards, righting the ship. The 'foils' on the OP are mounted in the opposite manner, generating opposite effect. If they generated any actual lift the ship would flip instantly.
- hliyan 12y ago
  Won't an air envelope reduce friction as much as a vapor envelope? RE: SWATH: their patent http://www.rexresearch.com/sancoff/sancoff.htm http://www.rexresearch.com/sancoff/sancoff.htm discusses hydrofoils and SWATH as prior art [0182], [0183], but fails to describe how their "buoyant tubular foils" (BTFs) [200] are different.
kghose 12y ago
Also see ekranoplanes http://en.wikipedia.org/wiki/Ground_effect_vehicle http://en.wikipedia.org/wiki/Ground_effect_vehicle (And hydrofoils, I was very excited by hydrofoils when I was a kid) http://en.wikipedia.org/wiki/Hydrofoil http://en.wikipedia.org/wiki/Hydrofoil
hliyan 12y ago
Detailed schematics here: http://www.rexresearch.com/sancoff/sancoff.htm http://www.rexresearch.com/sancoff/sancoff.htm
harywilke 12y ago
Isn't cavitation a bad thing when trying to be quiet in the water?
deleted 12y ago
[deleted]
dm2 12y ago
There are numerous problems with this ship but the main reason why it won’t be used is that the US Navy already has a very similar ship that has been in testing since 2006 and is all around better than the vehicle in the article. http://en.wikipedia.org/wiki/M80_Stiletto http://en.wikipedia.org/wiki/M80_Stiletto 50+ knots top speed, 4 x 1,650 hp engines can carry a landing craft, 12 troops, and up to 20 tons of cargo “A key feature of this vessel is that it can set up a network between a special forces team by launching an unmanned aerial vehicle (UAV) that relays information between the team and boat. The Stiletto can also carry surveillance UAVs to provide reconnaissance for the SEAL team, and, using a clustered supercomputer on board, will be able to send real-time images to the team on shore.” Cost between $6 million and $10 million each. For extremely stealth missions SEALs would use a underwater vehicle deployed from a C-130, another ship, or a submarine. http://en.wikipedia.org/wiki/SEAL_Delivery_Vehicle http://en.wikipedia.org/wiki/SEAL_Delivery_Vehicle “The 88-foot (27 m) long vessel has a notable hull design, an M-shaped hull that provides a stable yet fast platform for mounting electronic surveillance equipment or weapons, or for conducting special operations. The hull design does not require foils or lifting devices to achieve a smooth ride at high speeds in rough conditions. Its shallow draft means the M80 Stiletto can operate in littoral and riverineenvironments and potentially allows for beach landings. The faceted design suggests that the vessel has a low radar signature (i.e., stealth) in the frontal aspect and somewhat so from the sides.” http://www.naval-technology.com/projects/m80-stiletto/ http://www.naval-technology.com/projects/m80-stiletto/ http://www.wired.com/2008/09/stiletto-vs-dru/ http://www.wired.com/2008/09/stiletto-vs-dru/ http://www.gizmag.com/stiletto-experimental-ship-with-carbon-fiber-m-hull-design-tops-50-knots-60mph/5151/ http://www.gizmag.com/stiletto-experimental-ship-with-carbon...

37 points by Hoff 12y ago

idlewords 12y ago

This thing looks like it could really turn the tide in our fight against Cobra.

ch4s3 12y ago
Yeah too bad these stealth designs work like ass against WWII era long wave radar. Sure, you can't use long wave for targeting, but something this big sitting so high out of the water seems easy to hit with a shoulder fired rocket. It seems like these super high tech ships and aircraft exist mostly to create jobs in various congressional districts. Then the get sold on the mythology of a cold war nightmare scenario that never happened. oh well. at least we're safe from COBRA.
- lingben 12y ago
  "Hinges allow the struts to move up and down like wings. While parked, or traveling through shallow waters, they can be extended to the side." Maybe you missed this while scanning the article. This would allow the boat to sit high or low on the water; reminds me of the citroen cx which had high adjustable suspension.

thechut 12y ago

Reminds me of the villains boat in Tomorrow Never Dies [1] 1: http://i.dailymail.co.uk/i/pix/2011/06/19/article-2005464-0CA0FEB500000578-484_634x261.jpg http://i.dailymail.co.uk/i/pix/2011/06/19/article-2005464-0C...

sandworm101 12y ago
Which was based on the real Sea Shadow. http://en.wikipedia.org/wiki/Sea_Shadow_%28IX-529%29 http://en.wikipedia.org/wiki/Sea_Shadow_%28IX-529%29

rdtsc 12y ago

Another military device using supercavitation is the Soviet (now Russian) supercavitating torpedo: https://en.wikipedia.org/wiki/VA-111_Shkval https://en.wikipedia.org/wiki/VA-111_Shkval Max speed is 200 knots (230 mph) and it can go for almost 10 miles. That seems almost unreal, an object that size, going at that speed under water.

bazzargh 12y ago

Sancoff began contemplating ways to give back to his country. To him, that meant shifting his focus from medical devices to weaponry. That's a disappointing comment.

rexignis 12y ago

Nothing like this will ever compare with a submersible in terms of "stealth". Who knows, maybe there already exists a supercavitating shallow draft sub for the spooks to use.

sandworm101 12y ago

Not stealth. Far to many flat 90/45* surfaces and corners. Nobody with any understanding of radar was involved in the design of that thing. Not supercavitating. Supercavitation is based on cavitation, not sucking down air from the surface. http://en.wikipedia.org/wiki/Supercavitation http://en.wikipedia.org/wiki/Supercavitation. And the amount of energy needed to create a supercavitation void around those hulls ... The Shkval is essentially an underwater rocket and it still uses exhaust gases to top up the bubble in which it flies (see the little holes near the nose) http://en.wikipedia.org/wiki/VA-111_Shkval http://en.wikipedia.org/wiki/VA-111_Shkval. Not a hydrofoil. No foils. It looks to be a SWATH hull (Small Waterplane Area Twin Hull) another great Canadian invention. http://en.wikipedia.org/wiki/Small-waterplane-area_twin_hull http://en.wikipedia.org/wiki/Small-waterplane-area_twin_hull Who did this guy know at Businessweek to get this sales pitched turned into an "article"?

tectec 12y ago
It also reminds me of this Canadian invention: http://en.wikipedia.org/wiki/HMCS_Bras_d'Or_(FHE_400) http://en.wikipedia.org/wiki/HMCS_Bras_d'Or_(FHE_400)
- sandworm101 12y ago
  Ya, but that ship was an actual hydrofoil. The foils act like wings to generate lift from movement. The thing in the OP uses movable pontoons, buoyancy, to haul itself up regardless of speed. Note also that real hydrofoils angle their foils in parallel to the hull. It's essentially a dihedral effect like that of an airplane. As the ship lists one way, the foil on the downward side pushes more directly upwards, righting the ship. The 'foils' on the OP are mounted in the opposite manner, generating opposite effect. If they generated any actual lift the ship would flip instantly.
hliyan 12y ago
Won't an air envelope reduce friction as much as a vapor envelope? RE: SWATH: their patent http://www.rexresearch.com/sancoff/sancoff.htm http://www.rexresearch.com/sancoff/sancoff.htm discusses hydrofoils and SWATH as prior art [0182], [0183], but fails to describe how their "buoyant tubular foils" (BTFs) [200] are different.

kghose 12y ago

Also see ekranoplanes http://en.wikipedia.org/wiki/Ground_effect_vehicle http://en.wikipedia.org/wiki/Ground_effect_vehicle (And hydrofoils, I was very excited by hydrofoils when I was a kid) http://en.wikipedia.org/wiki/Hydrofoil http://en.wikipedia.org/wiki/Hydrofoil

hliyan 12y ago

Detailed schematics here: http://www.rexresearch.com/sancoff/sancoff.htm http://www.rexresearch.com/sancoff/sancoff.htm

harywilke 12y ago

Isn't cavitation a bad thing when trying to be quiet in the water?

deleted 12y ago

[deleted]

dm2 12y ago

There are numerous problems with this ship but the main reason why it won’t be used is that the US Navy already has a very similar ship that has been in testing since 2006 and is all around better than the vehicle in the article. http://en.wikipedia.org/wiki/M80_Stiletto http://en.wikipedia.org/wiki/M80_Stiletto 50+ knots top speed, 4 x 1,650 hp engines can carry a landing craft, 12 troops, and up to 20 tons of cargo “A key feature of this vessel is that it can set up a network between a special forces team by launching an unmanned aerial vehicle (UAV) that relays information between the team and boat. The Stiletto can also carry surveillance UAVs to provide reconnaissance for the SEAL team, and, using a clustered supercomputer on board, will be able to send real-time images to the team on shore.” Cost between $6 million and $10 million each. For extremely stealth missions SEALs would use a underwater vehicle deployed from a C-130, another ship, or a submarine. http://en.wikipedia.org/wiki/SEAL_Delivery_Vehicle http://en.wikipedia.org/wiki/SEAL_Delivery_Vehicle “The 88-foot (27 m) long vessel has a notable hull design, an M-shaped hull that provides a stable yet fast platform for mounting electronic surveillance equipment or weapons, or for conducting special operations. The hull design does not require foils or lifting devices to achieve a smooth ride at high speeds in rough conditions. Its shallow draft means the M80 Stiletto can operate in littoral and riverineenvironments and potentially allows for beach landings. The faceted design suggests that the vessel has a low radar signature (i.e., stealth) in the frontal aspect and somewhat so from the sides.” http://www.naval-technology.com/projects/m80-stiletto/ http://www.naval-technology.com/projects/m80-stiletto/ http://www.wired.com/2008/09/stiletto-vs-dru/ http://www.wired.com/2008/09/stiletto-vs-dru/ http://www.gizmag.com/stiletto-experimental-ship-with-carbon-fiber-m-hull-design-tops-50-knots-60mph/5151/ http://www.gizmag.com/stiletto-experimental-ship-with-carbon...