Military recon powerboat concept

[kach22i]

Originally Posted by BMcF

Sounds like a sweet model..and big. I like big..

I made three cut-out men out of foam about six inches tall. Somehow the scale change (making it larger) caught me by suprise.

I have to follow the drawings more closely now, this takes a little of the fun (sculptural and design aspect) out of it. One of the main reasons I like to build models so much is that it forces me to make things simpler than I tend to draw them. I leveled out some of my floor area level changes for instance (less tripping).

The main problem I discovered is that I deviated from the drawings for the roof openings. Roof mounted 50 cal gun turrets were first cut to only a 24" diameter (shoulder width). My previous drawings show 36" opening for single 50 cal and 48" dia. for a double 50 cal. These dimensions are based on the old Vietnam era PBR (bow gunner) patrol boat and SK5 hovercraft (roof gunners).

If anyone knows if modern gun fittings and openings are different (such as found on the roof of a Humvee) please let me know. This information is hard to come by and I've been scaling plastic models and photographs which I have collected over the years.

[kach22i]

Somewhere in this thread this design was mentioned, so I'm posting this here for future reference.

http://www.connormarine.com/pages/9/...=1111977204133

185' SES Catamaran, 100+knots, turbine powered, Designed by Connor Marine for new Transatlantic Speed Record

[WALKERS210]

Originally Posted by jehardiman

Boys....go look up SES 100A and SES 100B. Both SES's, different concepts, different designs, different support factors.

Today in high speed vessels there are not distinct types, but rather hybrids. Think of a design area shaped like a triangle with hydrofoils at the apex (solely supported by hydrodynamic forces), cats and monohulls at one bottom point (solely supported by hydrostatics), and ACVs and airplanes at the other (solely supported by areodynamics). Most power cats are along line between cats and hydrofoils, ekanroplanes along the line between hydofoils and ACVs. SESs are along the baseline, each design falling somewere between cats and ACVs depending on the distribution of lift at any given time.

I know this is an older post, I found it doing a google search for info on the SES 100's. In 1972 I was assigned to the Navy's newest test facilty SESTF (Surface Effect Ship Test Facility) based at Naval Air Station Patuxent River, Md. I have read some of the post but the one following the one I quoted from questioned if the bow seal was damaged that the SES would pretty much crash and burn. I brought up the exact questions to engineers from Bell Aerospace and the Navy pilot. I was told that it would take major failure like loosing the entire bow seal to cause it to nosedive. However the very first SES built was about 25 ft in length and had plywood bow and stern seals that were hinged to hull. It was powered by a Mercury 150hp outboard, with 2 Briggs and Stratton (mower) engines that provided the air flow for lift. It ran on the Potomic river and in fact had a failure of the bow seal which resulted in both crew members being killed. I know its been darn near 35 years and the program has long since been scrapped. But it was a sight to see when the SES 100B went over the HUMP (18kts speed it would outrun its own depression in water) then it was gone. 1975 SES100B running in St Andrews bay in Panama City, Fl reached a speed of around 110kts. The Sidewalls were designed to hold in the air for lift and provide a way to stop or reduce the side slip while executing a turn. Somewhere in my old pile of junk I think I still have pictures of the SES 100B and even the SES100A.

[kach22i]

Originally Posted by WALKERS210

SES built was about 25 ft in length.......... It ran on the Potomic river and in fact had a failure of the bow seal which resulted in both crew members being killed.

I did not know this story, how tragic.

I may have pictures of that test craft in my Jane's Surface Skimmers 1975-76, it's description sure does sound familiar.

[brian eiland]

Originally Posted by brian eiland

I assume you are familar with Dick Newick's tri-hull powerboat
http://www.yachtforums.com/forums/16142-post55.html

...or Peter Payne's work down there on Chesapeake Bay, Sea Knife
http://www.yachtforums.com/forums/16010-post47.html
http://boatdesign.net/forums/showpost.php?p=81761&postcount=8

In fact you might find this whole subject thread interesting
http://www.yachtforums.com/forums/general-yachting-discussion/2701-trimarans-bladerunner.html

_______________________________________________________
How strange...within a period of a week here we got messages from two fellows involved with the SeaKnife project. The second message came to my private email, and I inquired as to whether the two were the same person...no was the answer. So I'll post his message here as he may not be interested in participating in the forum, but his comments are worth repeating

Originally Posted by alexmeldrummr4

I was privy to the Navy plans and special R&D with the original secret KNIFE BOAT PROJECT in 1981. It was a fast attack PT style boat that could be lauched rapidly to persue enemy subs. The design called for two deck mounted torpedoes, a 50 cal gun, and room for three men. Design specs also outlined top speed to be no less than 100 knots in a sea state five. It's a appears the that the Sea Knife project was swallowed up by the stealth boat's design team. Too bad, they were onto something with that boat.

Originally Posted by Eric Bleicken

message: Brian:
I read you an article you wrote about Peter Paynes Sea Knife. I was the PM at DARPA who fought hard to get Payne's 65' Patrol Boat built for the SEALs. I still have the water color of the B&W picture you published with your article.
I continue to believe this is the route the SEALs should go.

Originally Posted by Eric Bleicken

I got to ride in Peter's 32 footer and we were able to go through some 4' wakes at high speed. I'm guessing 60 kts +. The boat hardly responded to these wakes. I became a believer very quickly. His designs stand on their own and the resistance I met at DARPA, NAVSHIPSYSCOM etc. was WIH (wasn't invented here). Peter felt that the only solid patent he had was the bow transom.

SEALs don't get to decide that the weather is not nice. They have to operate under extreme conditions. As I recall, Peter told me that if a boat can manage a state III sea it could function worldwide about 30% of the time. If it could operated in state V it could function 85% of the time. This is the critical issue in combat.

The SEALs MK V experiences as much as 20 G's vertical accelerations. Hodgdon's Yachts composite MK V version may reduce it some, but not enough. As long as the Navy insists on a displacement design, this problem won't be solved.

[peterAustralia]

I am a bit bemused as to why no one has mentioned the austal - grumman littoral combat ship, something scaled down from that might fit the bill. Maybe something in 60 to 70m range

My understanding is that 3 hulls has better ability to carry weight that 2 hulls, with everything else being equal

[brian eiland]

Here are some recent photos of the LCS 2 (to be USS) Independence . She’s at 43 knots here running at half power. NOTE the absence of a bow wave.

Turns tightly, also; allegedly this also was done at 43 knots...and from the look of the small bow wave, she’s still in the turn.

And then we have the massive helo deck big enough for a CH-53. Last time I talked with the SURFPAC guys years ago.THIS was the LCS they liked because of the huge storage capacity under that flight deck and the size of the flight deck.

Note that there is very little spreading wake. In fact, it does not look like a wake at all, just foamy water from the water jets. Somehow, at 40 knots,you’d think there'd be more wake

But she has one drawback, she’s strange looking but aerodynamically designed, is this beginning of a new design in ships?

[daiquiri]

Originally Posted by brian eiland

Note that there is very little spreading wake. In fact, it does not look like a wake at all, just foamy water from the water jets. Somehow, at 40 knots,you’d think there'd be more wake

That is an impressive lack of wavetrain!
I wonder why didn't they give her more flare up at the bow? I am thinking about it's seakeeping performance in high seas...

[brian eiland]

Originally Posted by daiquiri

...I wonder why didn't they give her more flare up at the bow? I am thinking about it's seakeeping performance in high seas...

The modern thinking is to not try and ride over the wave but rather pierce thru it. For that reason the top deck surface area is actually reduced up higher such as not to present a big area to the water that would force the bow down while piercing thru it.

[jehardiman]

Originally Posted by daiquiri

That is an impressive lack of wavetrain!
I wonder why didn't they give her more flare up at the bow? I am thinking about it's seakeeping performance in high seas...

You don't understand Navy thinking, i.e. littoral = no big waves. Only later will the need to cross seas or operate offshore continiously come into play. The design requirements only required max speed in SS 3, so if they used the maximum NATO envelope, that means 5 ft @ 8 sec.

Here is a quote from the press release of the sea trials of LCS 2.

Many of the test events were conducted in high sea-state and wind conditions (8-foot waves and winds in excess of 25 knots). Despite the weather, the ship repeatedly reached speeds of over 45 knots with propulsion and ride-control systems operating in full automatic mode, proving the effectiveness of the control systems and the highly efficient and stable characteristics of the trimaran hull form.

And the ship specs: http://www.ussindependenceship.org/overview_ship.php

8 ft waves = "high sea-state"

[kach22i]

Somebody built something similar to page one of this old thread:
http://www.youtube.com/watch?v=wnA6Q...ayer_embedded#!

[hoytedow]

Originally Posted by kach22i

Somebody built something similar to page one of this old thread:
http://www.youtube.com/watch?v=wnA6Q...yer_embedded#!

Awesome video!

[jehardiman]

Originally Posted by kach22i

Somebody built something similar to page one of this old thread:
http://www.youtube.com/watch?v=wnA6Q...ayer_embedded#!

I can't believe where the air intakes are...better not lose your hat back into one.

[kach22i]

Who brought the marshmallows?

http://www.youtube.com/watch?v=fDjKR...eature=related

[Anytec1210]

Back in the days (late 80´s) when stealth was the really new and hot thing some really smart guys in Sweden put together the "Smyge" to prove the concept of a fast and capable attack and recon stealth vessel.

In 1991 the ideas turned out in this.


A 27 meters (about 90ft) and 140 tonnes. Equiped with SA and SS missiles, torpedos and a 40 mm gun reaching up to 60 knots.

Since this was just a trial vessel they did not go into production but in 2000 those ideas turned into this.




and today ..