liveaboard flat hull design disadvantages

tuyhoabob, if you stick to facts and keep your focus on boats you will be fine and your input greatly appreciated.

Since you are brand new to the forum, and for anyone else, I remind you of the rules you agreed to when you signed up, including

 

True viking, fuel economy was not a strong suit for them but, they had big tanks and the fuel was free for us I'd hate to have to fill one up these days, that would hurt!! They also made a very nice clothes-dryer during the monsoon seasons, all 1500 hp.

We have the same problem with the motorbike tires on the Honda's I rent. If they sit for more than a week or so the tires need air. I only rent to foreigners so the tires and tubes are always new and I check the valves over, don't know what it is.

 

PAR, you seem to be overlooking the obvious. You wrote, "This is a pig of a boat, it's over driven, over weight (except the aluminum version, which is just slightly over weight) and generally only good for one thing, which incidentally happened to meet it's bid criteria. I've actually been on them and they truly suck at everything, unless you plan to be of (sic) dropping 50 tons of whatever on a beach."
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Let's examine your statement point by point.....

Point # 1..........

"This is a pig of a boat,...."

I suppose if your idea of good design is solely good looks and light weight, then yes, that might be true for many pleasure boats. Some of the boats you have designed are true beauties.........but they certainly could not fulfill the purpose that a mikeboat (LCM-8) would in a military environment........perform any assigned task, sometimes far over loaded, running aground with heavy loads routinely, often several times daily, and sometimes out of necessity, beaching at full throttle. Keep in mind that sometimes the "beach" might be rocks, tree stumps, or underwater engineered obstacles designed specifically to rip the bottom out of landing craft. (Try that with a lightweight design.)
On top of all those demands, the boat has to continue operating even if hit hard by enemy fire. Hull integrity, even when damaged, is a must.

See photo # 7 in my album.

The total structure, carrying tremendous weight, must stay together, operating in those extreme conditions, even if part of the hull is damaged or missing, until it can be repaired.

As far as your "pig of a boat" statement, yes.........I'd have to agree with you, and rank the LCM-8, AKA mikeboat, as a Pigboat..........much like the ugly, over powered, heavily armored A-10 Thunderbolt ground attack aircraft, famous for surviving tremendous damage, yet still able to fly back back to base safely, bringing it's pilot home.........the venerable "Warthog".

Yes, Pigboat will work. As an example of that "pig of a boat" toughness, one of our boats, loaded with 50 tons of military dynamite, took a direct hit from a Viet Cong mortar round, and survived.

See photo # 8 in my album.

Although the less sensitive military dynamite did not explode (no nitroglycerin contained in military dynamite), the load did ignite, and it burned with such intensity that it could not be extinguished. The boat stayed afloat. You might suggest that your comment "over weight" (implying over built) applies in this particular situation. I would counter with, because the boat held together, the entire cargo burned, rather than sinking, and loosing explosives in the depths that might later be recovered by the enemy, to be used against allied forces. The boat was a total loss, but it did hold together.

No matter if you are a boat designer, naval architect, or just an ordinary boat skipper that actually operated these boats daily........there is no doubt about the toughness of the LCM-8 design and construction; they can absorb tremendous amounts of punishment, and still keep working...........a real asset that was much appreciated by the men that depended on them in riverine operations carried out in Vietnam. *****************************************************************************************
Point # 2...........

"it's over driven........"

LCM-8 landing craft are not just designed to move cargo and personnel from ship to shore. LCM-8's are also regularly used as a naval ships improvised tugs, when no regular tugs are available, as when visiting some foreign ports.

An additional requirement for LCM-8's are to provide for assisting much larger landing craft off the beach, when those larger landing craft cannot extract under their own power alone......for instance, LST's........small ships.
As you know, LST's have flat bottoms. You may or may not be aware of the fact that LST's employ seawater ballast tanks, not only to secure the LST more solidly into position on a beach, but to provide cooling water for the ships's mechanical systems when the tide is out. Sometimes, the "suction" on a flat bottom ship of this size, after several tide changes, can be a tremendous obstacle to getting the ship off the beach. LCM-8's are "overdriven" because they are designed to compliment other vessels in amphibious operations; the total vessel package requirements are planned..........................................................
not just for the propulsion requirements of the single LCM-8, but for the total power requirements of an amphibious landing group.

Many places in the Mekong Delta had canals too shallow for tugs to operate.

See photo # 1 in my album.

Because of their shallow draft, LCM-8's were routinely tasked to serve as shallow draft tugs, moving large barges to be used as artillery firing platforms in the shallow canals of the Mekong Delta. Because riverine warfare meant fast moves almost daily, the tedious process of laying mats over the soft Mekong Delta mud, in sufficient numbers of pieces to support repeated firing from 105 mm Howitzer artillery pieces was not an option......too slow in laying/picking up the mats......the barge mounted artillery pieces were much more mobile, and more quickly repositioned as needed. Again, a task requiring a tough, "over driven" boat.........a LCM-8.

Boat design is not purely esthetics or number crunching, but a complete understanding of how to arrive at the best compromise to fulfill the requirements spelled out by the end user. Sometimes, the scope of the power required reaches far beyond the individual boat's power needs, but is designed in, for additional tasks the vessel may have to fulfill. That is the reason Sir, that a LCM-8 is "overdriven".
LCM-8's often replace tugs in shallow water amphibious/riverine operations.

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Point # 3..........

"over weight (except the aluminum version, which is just slightly over weight)..."

As far as your assertion that the boats are built over weight (implying built too heavily), anyone can look at the color photograph of the 34 being hoisted for new screws in photo # 9 in my album; look at the bottom of the 34........it looks like a half starved mare's ribs. If the scantlings were any lighter, the boat would not be able to perform over the long term in a combat environment. You, as a designer, must certainly know that to be true.....just as anyone else examining that photograph will see for themselves. The photograph shows the result of real world usage, in a combat environment......it says volumes about the weight of the boat and it's scantlings.


Many times, we operated our boats vastly overloaded, because commitments required us to do so. In particular, I remember one run when we had to get 105 mm Howitzer ammo to a remote firebase about to run out of ammunition. Our boat was the only boat available, and the full amount of ammunition was urgently required by the firebase. We actually had so much weight on board, that water was about 12 inches deep in the welldeck, where it was coming in through the scuppers. Take a load that heavy, and run up on a bank with snags and stumps on it.........you better have what you call an "over weight", heavily built boat.


Your comments "overdriven" and "overweight" have to be examined "piggy-backed", to be properly understood. Because these boats were designed to achieve a whole spectrum of tasks (with many of these tasks requiring a substantial amount of thrust, moving other, larger landing craft or ships), they are provided with substantial power plants. No talented designer would put powerful engines into a hull with slight scantlings, and no designer would build an extra heavyweight hull, and use anemic engines in it.
The whole LCM-8 package is designed to have sufficient power and sufficiently heavy scantlings for the hull to handle that power.....a well thought out package.
Personally, I think the folks that spelled out the bid requirements for the
LCM-8 did a fine job, as well as the naval architects that drew up the plans for this class of boat.
With the exception of making titanium LCM-8's (I cannot fathom the cost that would be), I don't see any way to make the boat lighter, and still have it built strong enough to still survive in a rigorous combat environment.

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Point # 4.................

You wrote, "only good for one thing", and that meshes with another part of your remarks, "they truly suck at everything,".

Paul, you could not possibly be more wrong with those assertions.
Some Army LCM-8's sometimes had improvised helipads installed in their welldecks.

See photo # 10 and # 15 in my photo album.

All herbicide defoliation missions were not just carried out by aircraft. LCM-8's from the 1099th Medium Boat Company were loaded with tank trucks equipped to spray heavy vegetation concealing dug in emplacements along rivers and canals.

Flame operations were conducted from mikeboats, to burn off the dead foliage weeks later.......another LCM-8 task. (Zippo boats).

One LCM-8 was outfitted as a floating shop, to make on-the-move repairs to damaged mikeboats, with crews often working around the clock; Mobile Riverine Force operations required almost continuous movements.

LCM-8's were modified constantly for the job at hand: mine sweepers, towing artillery barges, mobile mortar platforms carrying plenty of ammunition, troop transporters, mobile field hospital, mobile communications base, helicopter carrier..........in one instance, our unit even hauled a load of water buffalos as a goodwill gesture, to a village where some of the South Vietnamese farmers animals got blew away. All of the above tasks, performed by one basic design. I would call that a very useful and versatile design.
All of the above facts can be easily verified by documents held in NARA; look up the After Action Reports of the US Army 1099th Medium Boat Company, for 1969.

http://www.nara.gov/regional/stlouis.html


In my opinion, your statement, "they truly suck at everything" shows one of two things.

A Either you do not understand boat design.........which we all know you do understand thoroughly,

B Or if you can discredit the design as a "pig of a boat", (because you had to admit that a flat bottom boat in that size will pound), then you can somehow justify your statement of, "An 80' long flat bottom boat isn't going to pound. It will be longer then any wave train it encounters, for the most part."
Paul, apparently I've actually been on LCM-8's a lot more than you have. LCM-8's truly are versatile floating work horses, able to do just about anything, and absorb huge amounts of punishment while performing those tasks, and still survive in a combat environment.
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Point # 5...........

"and generally only good for one thing, which incidentally happened to meet it's bid criteria."
Am I missing something about this part of your remarks? Of course they met their bid criteria. Would you want our government to select sub-standard equipment for our military, that would fail in wartime operating conditions?

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Your cynical statement of, "I was in the same war as you Riverrat, though didn't have the joy of riding a LCM-8 in any of its versions.",.........what does that comment have to do with this discussion? "The joy of riding" comment drips with pure snideness.......not quite an attack, but definitely expressing an unneeded degree of surliness, not to mention that it also states that you have zero real experience with that type of vessel, except maybe one ride on them?

You wrote, "I do have a 100 ton masters ticket though and considerable experience in craft of every shape and size, including an unlimited sail endorsement and considerable time in flat bottom boats.", then you turn around and make a sweeping statement that flat bottom boats that size won't pound.......apparently, you haven't been in rough enough weather to make a flat bottom boat of that size pound.........despite your considerable experience.......... I have.

For what it's worth, I had a military license at age 19, and have trained on 45', 65', and 100' tugs, LCU's and some of the US Army's small ships. I operated LCM-8's full time for a year in Vietnam, and 1-1/2 years in CONUS. Attacking my experience was an unprovoked attack on your part. You do not have a clue about anything about me....you simply attempted to steamroll over my statements, because you were angry, for anyone to challenge your incorrect remark. If you think I'm wrong, then counter with cogent, well thought remarks; countering with personal attacks is merely subterfuge on your part. I almost left out.....I did not have a sail endorsement. So yes, you have more experience than I do, as far as sailing is involved.

Paul, I question your statements, but I'm not attacking you personally. My comments were simply countering your statement that, "a flat bottom craft that size won't pound." All of us in this forum expect you to stick to facts, not skewed, veiled attacks on observations of actual boat performance, or distracting efforts to minimalize the experience of anyone that disagrees with you.
Your contradictory comments of, "I've actually been on them", and then writing, "though didn't have the joy of riding a LCM-8 in any of its versions.", suggest to me the reason for your lack of understanding of the LCM-8 design parameters...........your MOS was not 61B30 or 61B40. You look at a LCM-8 strictly as a pleasure boat designer would, and do not fully understand all of the uses the vessel was designed for, nor the operating conditions these boats are often subjected to. The above remark is not meant in any manner to be denigrating, nor putting you down...........you design beautiful pleasure craft..........but you lack real operator experience with the military type of flat bottomed boat. The LCM-8 is a superb vessel for the applications it was designed for.

The paragraphs below are this site's rules, which I believe I have followed, to the best of my ability, without just rolling over, and not commenting about remarks you made that were inaccurate. Just gloss over the first sentence, and look closer at the second sentence.

2a.) It is never acceptable to insult or attack other members. Disagreement is healthy and beneficial to intelligent discussion but should be based always on ideas and factual information and never degenerate to a personal attack or insult. A violation of the above may lead to the immediate termination of your login and being banned from the forum permanently at the discretion of the moderator(s). More than one violation will mean the termination of your login and permanent banning from the forum without discussion. If you believe a post constitutes an attack against you or other violation, you are always welcome to report this using the "report post" icon on the top right of each post .

Hopefully, we can leave this subject to rest with no hard feelings. I like your boat designs, and enjoy reading your numerous comments and observations,
most of which are right on target. However, as a responsible person, I must comment on statements that are blatently incorrect, especially if a person is planning on spending a lot of money on a design/build that he is asking questions about. Tuyhoabob.........thanks for watching my back.

Best regards, Jim

 

Hmmm...you did a much better job of answering him than me, I'm impressed. As a point of interest I found 3 still being used by the Navy here, they're tied up right by the military pier near the An Phu bridge in Saigon. Couldn't get aboard due to military paranioa...funny...I could draw the systems and layout in my sleep but to them it's a big secret. Hey Jim send an email and I'll get pics sometome when I'm down there if you're interested in them. tuyhoabob@tuffast.net

 

"Actually FF the well deck of a mike 8 is almost 20' wide) pretty cool huh?"

A couple of beams and you could mount a double wide , and have room for a basement below, and nice wide decks.

Since these boats CAN travel, as a house boat it will be in very protected waters , and probably fairly seldom. So fuel burn would not matter much.

I can't see this running the AICW every spring and fall for 1500 miles each way.

Probably beached on a spoil island , or moored in a nice place.

I love it , a project that could be done in 30 days with a couple of friends , and a welder.

And as I am constantly the voice of the "Round Trip" boating costs (buy it then sell it) .

The house trailer ($5,000) might be scrap, but the boat should not loose a dime, depending on owner maint.

FF