Semi-sebmergible boat

[kach22i]

North Korea's secret weapon????????????

Why do I want one?:)

http://www.specwarnet.com/asia/NKSF.htm
Semi-sebmergible boat: A fast, three-engined boat used for inserting small teams of commandos. WIth a top speed of around 50 kts, it will race at high speeds towards it's target and then submerge for the final approach.
http://www.globalsecurity.org/military/world/dprk/images/semi_submarine.jpg


http://www.strange-mecha.com/ship/M-Sub/N-Korea01.htm
Hi Speed Submergible Boat (North korea)

Length : 12.8m
Width : 2.9m
Draught : 0.62m
Displacement : 10t
Draught : 2.5m
Engine : Engine X 3
Max Speed :
74 - 93Km/h (On the water)
85Km/h (Under the water)
Submarge Limit : 3m
Crew : 6 - 8
Special Equipment :
GPS, Electric wave absorption paints, Schnorchel

The boat was sunk in December 1998 by the South Korean navy Destroyer.
http://www.strange-mecha.com/ship/M-Sub/hssb.JPG

[jehardiman]

85 Km/h submerged at 3m???

I don't think so.

[kach22i]

85 Km/h submerged at 3m???

I don't think so.
I think you are right, that must be a typo..............thought I read that it can only go 3 or 5 knots underwater which would not be enough to fight the tide in some cases.

50 kts over water is not bad - kicking up a roostertail at speed is a dead giveaway with surface to surface radar though.

EDIT:
I found this....................

http://www.globalsecurity.org/military/world/dprk/navy.htm
On November 20, 1998, a North Korean vessel was detected and captured off the waters of the Kangwha Island in an attempt to infiltrate spies, who subsequently escaped to the North. On December 17, 1998, one semi-submersible under control of the Nampo Liaison Office was sunk by the ROK Navy while trying to infiltrate the coast near Yosu. The infiltration was detected by night surveillance equipment of our guard units prior to the infiltration, and a navy¡©air force joint operation sank the semi-submersible about 56 miles south of Yokji-do while it was making its way back to the North in the early morning of December 18.

[gonzo]

With a 10T displacement at that length I doubt it can do the claimed speed.

[kach22i]

With a 10T displacement at that length I doubt it can do the claimed speed.
It tends to go a little faster when people are shooting at you. :D

[ClarkT]

That is one weird looking hull form. What do the North Koreans know that we don't? Notice the inflection at around station 3-4? What's up with that? What about the extra thick gunwale there?

Looks like an aluminum hull with a FRP deck?

[kach22i]

Interesting comments.......................it does look a lot like a tri-hull or is it trimaran?

Notice the STRAKES on the side of the hull?

Makes you wonder what the bottom looks like. :cool:

Here is a strake on a car:
http://www.mulsannescorner.com/newsmarch03.html

Riblets are used on aircraft wings:
http://aerodyn.org/Drag/riblets.html

Shark Fins....vortex generators used on the new Mitsu:
http://forums.pelicanparts.com/showthread.php?s=&threadid=196276&highlight=shark+fins

Lex Fence on the F-18 Hornet:
http://www.nas.nasa.gov/Main/Redirector/redirector.php?old_url=http://www.nas.nasa.gov/Pubs/TechSums/

...............and some more:
http://www.aerospaceweb.org/question/planes/q0176.shtml

Dimples:
http://www.aerospaceweb.org/question/aerodynamics/q0215.shtml

Have you heard of the Bionic Dolphin?
http://www.innespace.com/

I know North Korea has lots of mini subs - don't think they have something as cool as the Bionic Dolphin though.

NOTE: In the Riblets link there is a section on flexible sidewalls similar to Dolphin blubber giving in to water pressure at speed. The flexing makes it go faster, perhaps though vortex generation or bubble captivation, I don't recall exactly.

[mackid068]

Awfully cool, but during WWII (I dunno if someone's already said this...) frogmen would use limpet mines and torpedo shaped minisubs. The Brits also had a submersable kayak.