Trimarans and the BladeRunner...

Great flashback there...the "Sea Viking" surface-effect-ship, or SWCM.

The choice of that platform option was not influenced by lobbyists or plus-up earmark money, in fact. Quite the contrary...it was chosen for certain attributes that the community that would operate it decided were valuable.

Fast forwarding just a little bit to ca. 1983-4...with Rohr's demise and the halt of the SWCM program, a complete digital ride control package (the first ever "production" version; all previous incarnations were R&D prototpypes) remained built but undelivered. By pure chance of luck and confluence of the stars, a prototype SES passenger ferry built and under test in Norway was found to be in desparate need of a ride control system.

And so began a long and fruitfull relationship with the Norwegians and their SES' that continues to this day..30 years later.

I guess I will have to take your word for it as I was not anywhere near that program at that time. It just seems to me when I read the latter part of that report that Rohr corp got that contract via some 'insider deal',.....

The next rumor we heard through the Squadron grapevine was that the boat was over weight and the weapon systems and major electronics had not yet been installed. What we did not realize until months after the initial weight rumors floated out was only the boat’s hull had been completed and no engines or other significant equipment had been installed. We later learned that the weight of the hull alone far exceeded the total fully outfitted design weight (8).

Then we saw her during a drill weekend training operation down in South Bay on a sunny afternoon. Forlorn, pier side, almost hidden in a backwater at the 32nd Street Naval Station, we were shocked to see how incomplete the large, ugly, dull, aluminum hulk was. We (officers and enlisted men) were all under the impression much more construction had been completed. We recognized immediately she was cursed and gave her the cruel but apt nick name of “Sea Brick” in stark contrast to her semi-official name of “Sea Viking.” Though the Sea Brick held a perverse fascination for us in the boat units (12 and 13), we had no strong desire to leap aboard and explore this sorry shell. While we in SBU-13 would take little side trips during our South Bay training ops to view her, I don’t recall anyone taking pictures or going on board, which would not have been hard on a Saturday or Sunday. This was fairly surprising knowing what an adventurous lot most of us were in the Boat Units with all the shutter bugs in our ranks including myself. It was readily apparent a lot of money had been squandered. With no powerful triumvirate of congressional, military and industrial support like that behind the V-22 Osprey who would spend even more obscene amounts of the nation’s treasure to try to make an elephant fly or even get behind a new functional design. We could all see we were going to be stuck with the PB’s for some time to come.

We finally heard the Sea Brick hulk was eventually towed up to Point Hueneme and used as a target. I think one or a few of the guys actually saw her up there dockside waiting to be towed out on a missile range. However, her cursed legacy had even farther reaching effects, than denying our generation a new patrol craft.

Historically most patrol boats were constructed at ELCO on the East Coast or Higgins Industries in Louisiana. Many of the Vietnam era boats were constructed by yards in Louisiana. The SWCL’s and PB’s were built in Washington State. This is not to grant a perpetual license to the older yards at the expense of start ups, but you have to wonder about awarding a contract to a yard that has no track record.



......insider deal like I think the M-ship program likely got started??

Lets see , who was that Congressman from out in that Navy area of Calf that got convicted of improprieties with respect to defense contracts?
Duke Cunningham

Simply put..no. M-Ships craft was indeed was an "inside deal"..a boat that came out of nothing but connections. Not to imply that there have not been more than a few of those..of course, there have been.

Rohr was actually in the running as a finalist in the bidding for the 3KSES frigate....the large-scale SES progrm that preceded the SWCM by almost a decade.

OK..or not. I still regularly sit down to dinner with those who were..those still with us, that is.

P.S.: the source you constantly reference is/was remarkably (or perhaps "limitedly" is a kinder term) uninformed and even more remarkably biased. But to be fair about it..that's about par for the course in this industry, isn't it? When we were working with the Smyge and designing the Swedish YSM200 SES Corvette, there were some in that navy that also had some very long knives out for anything that was not a "conventional"monohull frigate solution.

So it seems to go..everywhere.

Oh well, I'll just let that subject go for now. I only brought it up after I read that WarBoats.org report.

I was really going back to look for other Sea Knife information that I had never found when I made my first postings on that vessel. I'll post some of that when I get a bit more organized with the info.

Have you, in your searches, come across anything about Peter's "Wave Strider" too?



And if it makes the ending of the Rohr SWCM story any easier to digest....many (including myself) believe that its premature demise was a blessing in disguise; the design had taken on so much weight that it's performance would have been mediocre at best and just plain awfull at worst. SES designs simply don't have much margin for error when it comes to weight management.

I haven't seen mention made of a 'Wave Strider' ?

In this paper I saw mention of the FICATs (Favorable Interference CATamaran), and the Gayle boats
http://www.dtic.mil/dtic/tr/fulltext/u2/a081325.pdf

...and in his patent paper I saw a quite different version (sort of a tri-hull configuration) of his idea that had no specific name if I recall.....below

....the Gayle boats...another 'multihull' theme

In those pictures the ride looks great but give it some waves and it gets bad.

Look at this video National Geographic Inside 21st Century Warship CONVERT 720p HDTV x264 MoTv - YouTube

Look at the 21:08 point in the video and she is really rolling doing the "vomit comet" type of movement. Not very comfortable.

I know there are planes fore and aft on the center hull but I do not know if they are actively controlled. It obviously could do with a much more aggressive roll control to decouple that pitch and roll movement.

http://www.3dmodels.co/wp-content/uploads/2011/09/USS-Independence_05.jpg

I'm sorry, but I don't see this as excessive motion for a ship at sea.

Certainly it interfered with their launching that experimental detection equipment, but get aboard a conventional destroyer in a good sea and see what 'motion' is all about.

There is a new variant of this LCS design out there now,....referred to as a frigate now...
http://www.defensenews.com/articles...vy-still-searching-for-path-to-a-bigger-fleet

Some interesting old stuff on this subject thread.
https://www.yachtforums.com/threads/trimarans-and-the-bladerunner.2701/page-7

BMcF, are you still around?
https://www.yachtforums.com/threads/trimarans-and-the-bladerunner.2701/page-7#post-42853

Just reading back thru this subject thread this morning, and this posting popped out Thought it might be of interest considering our current situation over in the Straits

BTW Lorne Campbell, I was at one time looking to adapt the hull shape of your smaller BR vessel into a hard bottomed RIB
I don't know why someone doesn't come out with some small tenders making use of a foam collar (D-shaped) in lieu of the inflatable tube collars. In general the full rounded inflatable tubes really cut down on the interior space available in a small tender. And the 'inflatable' aspect adds to the complication/expense of these vessels.

Here is an idea I put forward a number of years ago. Granted it is a little complicated itself, but could be simplified.

brian eiland said:
...a cover ltr I sent to a few persons several years ago....thought there might be some interest

Over the past few years I have been conceptionalizing a small RIB (Rigid Inflatable Boat) tender for the use on cruising sail and power vessels, and sportfishing vessels in particular. It would put emphasis on a number of enhanced features that I do not believe are adequately addressed in the current market. I had written briefly on two previous occasions:

1) I was searching for a short, wide, open-transom tender/dive/sport craft that could be carried on the front deck of a gamefishing catamaran of my design (preferable two such tenders). I was seeking a relatively small craft that comfortable could carry 4/5 persons with some dive and/or dive/fishing gear. Too many of the existing RIBs are too confining in their interior space, particularly with their big round tubes. I wanted two persons to be able to sit on the tubes directly across from one another, and yet still have the leg-room and passage room to clear a central straddle-seat that might house a jet-ski type power plant. That would necessitate a fairly wide craft with a central hull that could house the water-jet drive unit. A wide craft needing a central hull rules out the cat configuration. I could have a transom for its structural contribution, but it needs to be ‘open’ to allow for immediate evacuation of any water that might swamp it as a result of a large wave washing over the bow stowage area of the mothership. With width I could accommodate the people without excessive length, and thus keep the boat size small and light-weight for the continuous hoisting service it will experience.

2) To another party I had written, “you chose to build your own tender. I have one in mind myself. It would be a RIB, possible with a foam collar rather than inflatable tubes. It would be virtually transom-less, or at least maybe just a rigid frame at the transom. The purpose being it would totally self-bail in an instant when subject to a big wave, and particularly when stored on the bow as with many sportfish vessels. It would be ‘extra wide’ for its length for increased capacity and ‘across the aisle seating’. It would have a modified ‘tri-hull’ bottom akin to XXXXX for superior performance in a chop as opposed to shallow deadrise of a very wide deep-vee. It would have a central saddle seat that would cover an optional inboard jet-ski style engine in lieu of a traditional thief-prone outboard….also safer no-prop diving usage. Ultra light model in carbon fiber, traditional model in stamped ABS.”

I made a trip to the Miami boat show this Feb 06, and I was disappointed again. As I look thru the market I’m not finding a RIB tender/sportboat that could be carried on deck, or in davits, that is really ‘self draining’. They all appear as a captive ‘tub’, that if flooded by a random wave would become a very heavy ‘big bucket’ of heavy water hanging from the davits or sitting on the foredeck. So I am seeking a virtually ‘transom-less design’, or at minimum a ‘framed-transom’ that would allow for very quick water egress.

I also find most of the smaller RIBs to be very confining and tight on the interior space as a result of the full diameter tubes utilized in their design. The actual width of the boats between the innermost tube sides is very confining with respect to allowing for two full size adults to sit across from one another, let alone a steering console, cooler etc. Then if you add in all of the ‘stylized’ seats for passengers, center console for driver, engine mountings and drains, etc,etc, you end up with very little interior volume to carry people, dive equip, etc, and all of those other items (food, supplies, bikes, etc) being transported to and from the shore. Remember, in the islands your tender becomes your car!!

One solution to increasing the onboard space of any RIB is to make use of only ‘half-round’ or ‘D-shaped’ buoyancy tubes at the beam extremities of the craft. This idea is at the core of the ‘SAFE’ system (I’ve attached a reference drawing). These ‘tubes’ might be constructed of either an inflatable material as normal for the current industry, or simply be a foam collar that might be glued on, or a combination of both.

Another solution to increasing the onboard space of the smaller RIBs is to make them wider…exaggerated wide. One manufacturer currently refers to this as his “wide body” models. The problem here is the deadrise angles at the bottom surface of the hulls become pretty small, or as it might be termed more ‘flat-bottomed’ rather than V’d. This results in a vessel that slaps or pounds more on the water surface, particularly a choppy one. And this flat bottom loses it directional preferences (control).

My design reconfigures the bottom of the RIB into a sort of tri-hull arrangement. This totally changes the shallow deadrise equation of the main hull, and provides two ‘channels’ that allow for a sort of air suspension within them. The outer rib keels, or what might be termed sponsons of the tri-hull configuration, act to contain the channels themselves, provide additional buoyancy at the extreme beams of the vessel, and provide a turning edge much like the tunnel sides of the older tunnel-hulled craft. These outer sponsons do not extend forward to the bow area of the craft, which might be confused with being similar to the old ‘cathedral hull’ that was so poor about pounding in choppy waters. It’s totally different. It’s referred to as a stabilized monohull, a slender monohull shape stabilized by two outer sponsons. The more ‘convoluted bottom shape’ of the design will lend ‘form strength’ to the bottom surface, as well as longitudinal rigidity to the whole vessel, allowing for a lighter fiberglass lay-up to achieve proper strength than is the case with the large flat-panel areas of the traditional V-bottomed hull.

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