Autonomous Submarine Yacht Project, Funded and Started. (18m Oceangoing Yacht Submarine)

Private Owner California. Building Site Cartagena Colombia Caribbean. Handover tour Panama Canal - California. Project start 14 October 2007.

27 Aug 2007

Hi Wilfried,

I've been a great believer in concrete submarines for many
years. I think this is the only viable way to make a safe
affordable large private submarine. I'm very interested
with your offer to build concrete pressure vessels at 331euros
per ton.

I would like to buy a 100-200ton concrete submarine pressure vessel from you. For maximum operational depth, I would
like 1000m with a fairly large safety factor, but would be
willing to take less if that isn't possible. For delivery
a much shallower operational depth is fine. The 1000m
operational depth would involve a complete refit and would
cost me a lot of money in view ports (as well as other
thru hull fittings, I'm sure).

I'm siding more towards a 200ton submarine, but willing
to explore the idea of 100ton.

My biggest initial question is, how long will it take
before I can take delivery of the hull? This is mainly
to figure out logistics of fitting out the sub. I'm
considering quitting my job and working on the sub full
time, but want to aviod wasting time by waiting for
parts which I could start collecting now.

I'd seen pictures of your proto-type concrete submarine
a long time ago, and was very excited when you joined the
psubs mailing list and could give us more information.

I have been working on a more detailed specification which
I can pass on to you. I've read
(thanks for creating that website), including about the
two similar projects you've been approached with already,
so I feel I have a reasonable understanding of what you
hoping to do. I'm hoping your venture is very successful.

Looking forward to hear back from you.


Hello Ian,

...For maximum operational depth, I would like 1000m with a fairly large safety factor...

Well, operational depth of 1000m would require a unmanned test dive to 2000m - better 3000m. The cost of operation set up to bring a 200ton sub to 3000m with a lifeline that can recover the boat if something went wrong just to get at least the info will be by far more expensive than the building cost.

Still keeping an uncertainty factor about long term and cyclic effects if all goes well.

The only thing we know for sure for now is that in modern concrete construction buildings like dams tunnels and oilrigs made of concrete can take some 300m over very long time.

So although the destruction depth for a hull as my prototype might be well below 1000m - operation depth never should pass those proved 300m without doing the corresponding 1:1 model long term and cyclic test series. What i have done so far on testing concrete for deep divers, and what stachiw et alt have published suggest linear behavior without big surprises of destructive seeping water cut effects etc... but this is all done on very small models. So 1000m is far below what can be considered tested sufficiently to risk human lifes on it. I would bet a couple of dollars on a model test not lives in a real submarine.

So if loosing the boat during testing is not within the plan we should stay at operation depths much shallower maybe 50m and a unmanned test dive to 150m to stay on the safe side.

On the long term a boat of the prototype design could push operate limits down to 300m and finally push the limit to 600m still maintaining similar safety factors as TROLL platform in north sea. Keep in mind that norwegian contractors lost a oil rig pushing the limits to 300m - So pushing to 600m includes serious risk of boat loss. And finally the required view ports will push the cost a lot up.

All deep diving below that limit would require a different (deep diver) design with one or more spheres as pressure hull and a outer hull for streamlining.

So while live aboard and yachting is the purpose, keep it shallow is keep it safe and affordable.

The 100 ton version is kind of minimum for live aboard in confinement experiments. A real floating and diving living space is nearer to 200 tons. The bigger the sub the easier is shore independent operation - this includes live and work aboard while outfitting.

From building start to hand over i plan a time schedule of 1 year for a bigger boat of 200 tons.
At the moment i am available but i have 7 serious projects in "talk about" phase. (yours is nr.8)

I have no idea how many of them finally will come up with a building start green light and when.

A possible worst case would be a green light from 8 projects in september. Somebody would have to wait for his hull 8 years - or i must figure it out how to produce parallel several hulls.

For the moment my politics is "first come - first serve" concentration on one project at a time.

Let me hear your thoughts...

Cheers, Wil

Hi Wilfried,

Thanks for the quick reply.
The only thing we know for sure for now is that in modern concrete
construction buildings like dams tunnels and oilrigs made of concrete
can take some 300m over very long time.
So, it sounds like a 1000m operational depth for a concrete submarine
isn't really realistic at this time. Perhaps when more data is avaliable
and somebody has invested time and money in testing (and maybe ABS
certification). I kind of suspected this and am willing to go with a
shallower operational depth. A 300m maximum operational depth (requiring
a refit and unmanned testing after deliverly) would be nice, 50m
operational depth on delivery is fine. I also consider that I may
never endup refitting for a 300m operational depth, maybe 150m, or
even keeping it at 50m, but having the option to refit for a deeper
operational depth is a feature I would like (if possible).

The 100 ton version is kind of minimum for live aboard in confinement
experiments. A real floating and diving living space is nearer to 200
tons. The bigger the sub the easier is shore independent operation -
this includes live and work aboard while outfitting.
I think 200tons is the way to go.
From building start to hand over i plan a time schedule of 1 year for
a bigger boat of 200 tons.
A one year construction time is fine with me, this give me plenty
of opportunity to prepare to receive and outfit the submarine.
At the moment i am available but i have 7 serious projects in "talk
about" phase. (yours is nr.8)
Great! I'm glad to hear you are getting a lot of interest!
A possible worst case would be a green light from 8 projects in
september. Somebody would have to wait for his hull 8 years - or i
must figure it out how to produce parallel several hulls.
So, 8 years is probably too long for me to wait. I would probably
start construction on my own, either a concrete (I've been thinking
about and research for this for years) submarine yatch or a small
steel psub (K350 or something similar).
For the moment my politics is "first come - first serve" concentration
on one project at a time.
I may have made a mistake waiting until I had all the funds to
complete the project before approaching you and should have started
dialog with you a lot earlier.

It sound like you are waiting for the one of the projects to give
you the green light so you can start construction. Other than a
deposit (you mentioned 50% down payment on your website), what
would you need from me before you would be able start construction?
If I'm able to supply you with the funds and required information
in September, and nobody else has, would you be able to start
construction on my submarine by October?

I'm not trying to "skip the line", just understand what position
you are in. Although, having somebody who is able to provide the
funds and is egar to start construction, maybe help some of your
other potential clients move to the "green light" phase faster.
Like I said before, I want you to be successful, although I would
very much like to be one of the first people to purchase a submarine
from you, I'm going to happy as long as somebody does.

I'm going to clean up my specification document and send it to you.
I'm 100% commited to owning a submarine and I finally have the
resources to fund such a project.


Hello Ian,

The most probable destruction depth for the hull i will deliver is 1200m - so operational depth down to 400m-600m under required safety factor 2-3 should be possible after view port refit and extensive tests but i have no hard data on this.

General purpose of the prototype was testing submarine yachting - not deep diving. Going out of scuba diving range is a risk i did not take to avoid prototype loss.

200 ton is OK for me, this is a size where ocean crossing is not a confinement experiment. (see Ben Franklin)

To get started transfer of funds (50%) is the basic requirement. I would also need some info about your identity i can only build boats for clearly identified customers. This is to keep my back covered and also a requirement for the fund transfer.

If you will fund in september we can have building start in october and hand over in october next year. At the moment there is no waiting line - not yet - so immediately building start is possible.

I assume that building your boat, document it, and having it show up in yacht ambients will trigger many orders and we will have to think about waiting lines and parallel projects a lot then.

I would like if you could be part of this new "concrete yacht submarine industry" we are going to start in some way on long term.

This is also the mayor reason why i want to keep it shallow for now and stay far away from testing the deep dive limits out - having a non scheduled boat loss in a deep dive test would not only be a cost factor - it would also be a "marketing Chernobyl" for the concept of concrete submarine yachts in general.

Let me hear your thoughts...



Hi Wilfried,

what type of documents would you are require for my identification?
Photocopy of my California drivers license?

Payment method would by via a wire/electronic funds transfer?

A little about me:

I understand that it's in our best interest to avoid a PR distaster
by loosing a hull. Refitting for deeper operational wouldn't
happen for several years - and will probably be done outside of
the US where I can take the sub out of the water cheaper.

I'm trying to keep the specifications simple so that the hull is
easy to manufacture. Please let me know if there are things
that it would be best to skip or address in some other way.
Also, if there are things that are easy to include and might be
useful later on. I've listed my basic specification below.
I've include the propultion specs as well, although I
understand that you will be delivering with a provisional
diesel only, main engine and generators will be supplied and
fitted by me. But would be interested in your feedback
(am I on the right track).

I'm assuming that since this is concrete, it should be relatively
easy to add additional thru hulls for other equipment (sonar,

Also, I will try to get some rough drawings together so you
can get an idea of what I'm thinking about for layout.

200ton Concrete Submarine Yatch
Length: 20-24meters?
Diameter: 4meters

Operational dive depth: 50meters (before refit)
100-300meters (after refit)

Surface range: 3000+miles
Submerged range: 30miles, 4-8 people, 1 week (with 3x emergence)

- 1 forward view port, diameter 1meter?
- 6 - 8 side facing view ports, 3-4 per side,
all mounted on the forward section of the hull,
diamter (50-100cms?)
- 1 hatch leading to the sail
- 1 hatch on the forward deck (for possible docking
with a small sub)
- thru hull aft of sail hatch (30cm)
- thru hull in stern for exaust port
- 1 hatch on the underside, (for possible docking
with an underwater habitat or future diver lockout)
- single shaft
- tunnel for bow thruster (30-50cm)
- tunnel for stern thruster (30-50cm)
- engine/machine room wall 10cm thick,
rear third of the hull would be machine space
- 4 keel thru-hulls spaced evenly all the center line
for drop weight release mechnism
- floor near the bow is slightly lower than the
main floor (to increase head height around forward
view port)

- diesel engine direct drive 100hp
- electric motor direct drive
- diesel generator 100hp? (or 2x 50hp)
- batteries ??
- diesel fuel (3000liters?)
- electric bow truster
- electric stern thruster

Hello Ian,

Thanks for your e-mail

The identity is necessary because i have to present this in written form of a "naval artefact construction project" to DIMAR which is the entity in colombia to regulate al "floating naval artefact", beach and waterzone construction issues. To present i need to let clear who is the owner, site manager, where funding comes from, how the construction will affect nature, port installations, tourism, etc...etc...i can get this pre building paperwork trough in some 30 days estimated.

Before we come to this we might explore some alternatives. As i get from your earlier mail you are in california - so hand over would be california which includes a expensive panama canal crossing if we start building in colombian caribbean area.
A building site in the pacific region in colombia is not viable due to several issues that include climate, security, topography, etc... there is just one port - buenaventura - the rest is basicly jungle down to the shore - no infrastructure.

I was thinking about the possiblity to move building site to another south or central american country or even up to california - what is labour cost/hour in california ? Is a hand over in florida a option...?

Let me hear your thoughts on this...

<I'm assuming that since this is concrete, it should be relatively
<easy to add additional thru hulls for other equipment (sonar, lights).

Yes, in general it is that easy like drilling a hole putting a cable whatever trough and reclose with fixation cement epoxy silicone or similar, there is no weakening or crack initializer function to fear as tension forces are taken by the rebar anyway. For bigger structures like later added hatches diver chambers etc make sure that rebar gets connected the way you would do in concrete building.

What concerns layout i suggest to stick in general to what has been tested and proven in the prototype. I am not a friend of making the plans on a dry writing desk - just to find out that - your ideas what would be a good - and not so good - will change a lot later when you get some practice with a yacht submarine.

I always say you have one set of ideas in first place - and another set of ideas when you do submarine yachting in practice. The best way to do it is keeping design engineering and practical building and testing very close together, trying to go 1 step at a time.

All the elements of your design list are a "can be" just keep in mind that building a diver chamber is building a pressure vessel inside a pressure vessel that requires the same amount of testing security and cost as the submarine hull itself, and can produce the same amount of deadly failure. Bottom hatches are elements that are present in small subs that come out of water dayly so you can inspect them properly - a barnacle or a bit of rust could kill you. I asume this is one of the reasons why navy lock out sistems are in the UPPER area of the boat that is inspectable on suface (DSRV) etc...thruster tunnels are in superstructures outside pressure hull never go trough pressure hull. Multiple hatches - think in murphy - someone will dive with a forgotten hatch/valve open...some nasty accidents...the less openings the better. Drop weights - mechanism will rott - this is only for small mothership operated subs - take a safer navy (saddletank blow out) aproach for emergency lift on a submarine yacht. Diesel direct drive - vibrations can make shaft seal leak.

In gerneral you need not make a final decision on all that at building start. Let your ideas about sistems and engineering elements that fit best evolve with the boat and its practical handling.

View ports of 1m are realistic. This also allows to put later a steel diver chamber in one of the portholes on upper side without changing much in hull configuration. Number of view ports is Ok, 2 diesel can be, 100hp can be - can also be less. 3000 liter tank and a lot more can be. Range of 3000 miles and a lot more can be. Some electric can be - but you will be surprised how little battery you really need in practice. Floor down is OK.

Hi Wilfried,

For identification it sounds like we should draw up a declaretion of
indentity or find an already existing one, or maybe you have one,
which I would have notarized in US by licensed notary. This is
probably something we can start on soon.

California is a rather expensive place. Hire day labour (mainly
undocumented workers) is $10-$15 per hour, minimum wage is around
$6 per hour. Renting a place near ocean accessible water large
enough to build the sub will be expensive, if we got very lucky
then we might see a place for $1000-$2000 per month, but from
what I've seen so far, it might be closer to $3000-6000 per month.

How much is it to pass through the Panama Canal? From searching
on the web, if the sub is under 24meter, when it would cost $750.
Maybe there are other "hidden" expences I don't know about, such
as hiring extra crew to handle the boat during lock transfer.
If this is the cost, I would willing to cover the Panama Canal
Toll. Panama Canal Toll rates:

I'll remove the bottom hatch requirement, less stuff to maintain
under water the cheaper. I will stay with the two deck hatches,
later on a steel diver lockout could be added to one, allowing
for a diver lockout without maintenance issues of a hard to get
to hatch.

I think if the drop weight release mechanism is made of a more
corrosion resistant material, say stainless steel, and tested
once a year (where the expensive drop weight can be easily
recovered), replaced when needed, it should be ok. Maybe this
is something I should add after I receive the sub. I'm not
fully comfortable with a civilian sub without drop weights.
But, as you said, this type of decision doesn't have be made
until later.

On your website you mensioned that it should be possible to replace
viewports without taking the sub out of the water, would it also be
possible to add thru hulls below the water line without removing the
sub from the water? If I'd be interested to know how.

Another question I have regarding fitting out the hull. I want
to keep the hull as streamline as possible, when adding lights,
it would nice to keep them recessed in the hull surface so the
don't protrude too much. How deep of a recess (if any) can I
make without effecting the hulls strength? I guessing this
depends on the thickness of the hull at the point I want to
make the recess.

The stern thruster could be built into the tail structure, but
for the bow thruster it's going to be hard to add without
creating some sort of "bump" to the outer hull. I've considered
added a free flooding structure to the bow, extending the nose
of the submarine a few feet while maintaining the lines. However
this will probably require removing the sub from the water
to do so (which it would be nice to avoid). On the other hand
it would be a nice place to add extras, robot arm, scanning
sonar, sensors, cameras, etc. and well as housing the bow thruster

About the cost, I'm budgeting $90,000usd for the hull and another
$90,000usd for out fitting and taxes once in the US. Does this
sound realistic? Of course anything I can save during the US
fitting means I can go without a job longer and spend more time
fine tuning and operating the sub.


Hello Ian,

Identification may be sufficient with a social security nr. I do not think we need notarized papers...

The labor cost factor between california and colombia is factor 20 then - prohibitive for our project.

I checked on panama canal - we should be fine going this way. Hidden cost should be 4 long panama lines and helpers to hold them (info from yacht owner) and a canal pilot.

Bottom hatch - good choice to have lock out on upper side.

Drop weight - we can include 4 hull trought in bottom area - to keep the option.

Viewport change without need of take boat out of water. - Yes when you take sand ballast out the hull floats on centerline - you can turn it around and access viewports and bottom area for replace and repair. You also can change shaft and propeller without taking boat out - the prototype design is made to do anything including full repaint (in 3 steps) floating on water.

Recess in hull - in general you can do in the hull what you would not doubt to do in a structural column in a building - drilling some holes is OK - taking out a "mayor part" of the material not.
The viewports create "holes" of 1m diameter so a by far smaller light will not do a weakening - but avoid it in the hull part between viewports that already have to take higher load then the rest.

We can have a overhanging saddletank above the front port (similar to a k-boat) this tank could have a bow thruster - i had no saddle tank on my prototype but i had a series of test with attached saddle tanks and found out that the emergency lift that provide those kind of tanks is a great feature you also get a kind of area to add and store sistems and things outside the pressure hull . So i would recommend a saddletank similar to euronaut and UC3 just not that angle cut but more whale back shaped.

I don´t think that you will need half of the budget for outfitting and register, according to US psubbers the register of a sub in united states is quicker and easier than a car trailer.

Cheers Wil

Hi Wilfried,

Rotating the hull in the water, nice idea.

I can send you (or fax) photocopies of my driver license and ID
page of my passport. I'll send SS# seperately. This should be
enough for the identification? Let me know your address and
I'll send these off to you in the next few days.

Also, which bank would I be transfering the deposit to? I do
main banking with a Credit Union and there are certain restrictions.
I will need to check with them that they can make the transfer, if
not that I will need to open an account with a larger bank.

So, you seem to have a good idea of what I want, and I feel I have
a good idea of what you'll be providing me. At this point I'm 100%
commit to doing this. The only thing I'm waiting for is for the
money resulting from the sale of my company to be deposited in my
bank account so I can send you the deposit. I did approach my Credit
Union about a loan to cover the deposit so I didn't have to wait for
anything, but they where not able to give me close to the full amount.

Also, do you have contract for building the sub, or will we have
to write one? What else would we have to finalize to "seal the deal"
as they say?

I've attached two imagines. One I took from your site and made the
modifications I was talking about (I left your copyright on it), you
can see, I'm sticking to your design as much as possible, only minor
changes. The second I rendered to get an idea what it might look like.
I've left off the second hatch and some thru-hulls, since I'm still
decided on the exact locations. I notice your drawing is has the
pressure hull at 4:1, while mine is 6:1 (a more efficent, speed wise,
ratio). It's probably not going to matter too much to me what the
ratio is, so long as it's 4:1 or longer, but not much more than 6:1.
I imagine you will want to stick with 4:1 since it worked in the

Please let me know if you prefer I don't attach imagines to email,
I'm not sure what type of internet connection you have. Hopefully
these are small enough not to cause any problems.


Hello Ian,


Best Bank for me would be .... which also has presence in united states. I will open a seperate account for this project. In general to receive funding from United States i have to present a paper what funding is for.

So a building contract is necessary for both DIMAR licence and fund transfer.

I will send you a version of a building contract in this days.

The 1:4 ratio is necessary to have ballast sufficently deep to be stable in static dives.

The building method allows a almost unlimited flexiblility where to put viewports, thru-hulls, hatches. So we can still change those details during construction - i will send you digital photos from the construction site - so you can check on things like ergonomics with a mock up.

Got your pictures, there is no problem with pictures as long as they are not bigger than 500k so we can interchange pictures easy - larger ones i can upload to the website or to a picture exchange site.

Kindest Regards,


Those numbers come out with a length to width ratio of 5:1. The hull
looks very nice.

I'm mailed off a copyphoto of my UK passport ID page and CA drivers
license to you, express mail. You should get it in five days.

Attached is a rendering of hull (ignore the sail, just playing round
to figure out the hatch positions) using the numbers from the imagine
you sent me. I like it! I think this will be a very efficient hull
if I can keep the number of external appendages low.


Hello Ian,

Thanks for the picture, looks good !

Keep in mind that the frametable gives the inner space of the submarine for mock up purpose - you must add wall strength according to the geometry of the prototype depending on hull diameter to get outer diameter.

The outer dimension of the sub on the drawing is 6m x 25m. (ratio 4,16) This would be some 450 tons.

A boat of 200tons would be 18,4 x 4,6m with the same lines, and cost 200 X 331 euro = 66.200 euro.

This would be 90.227 USD.

Thanks for sending ID - i can work it into the contract text then.

Having the deck behind the sail as in your rendering is a very good idea - on anchorplace the nose of the sub tends to point in wind and wave direcction - therefore deck before the sail gets washed but the sail sends the water to the sides so that you still can step on deck behind the sail in wave conditions without getting your boots filled in transfer.

To keep the number of appendages low is very important. Whales did not only loose their legs during evolution they also reduced very small appendages like hair and maintain even the genitals in streamlined skin pockets. So long distance cruising obviously brings up a very strong need of keeping the shape completly appendage free.

The saddle tank area will provide you with a option to add things and sistems and cover them integrated into a streamlined shape. This area will stay easy re-designable as it is thin walled and above surface. So you will be able to rebuild redesign and refit this saddle tank area without touching the pressure hull the hull integrity and without a need to take the boat out of the water.


Hi Wilfried,

thanks for the correct dimensions. I was getting very used to
the idea of that 450ton sub! If I could afford it, I would go
with 450ton, but that would introduce problems finishing the sub
once I had the hull (also, I would need to keep my day job and
it would take a long time to finish).

I've updated my computer model to fit the dimensions you provided.
Also, I was able to draw out a 1:1 version of the sub in sand
yesterday to get a feel for it's size and layout.

I've attached an imagine of the sub with the nose bump for the
thruster tunnel and external tank (again, the sail and tail are
just place holders). The 5:1 ratio hull looked really good with
nose bump on it, the 4:1 ratio still looks pretty good, but not
quite as sleek as the 5:1 one. I'm still working out if it's
possible to integrate the stern thruster into the tail, or if
I'll add a hump on the stern for the thruster tunnel.

Interestingly, when I did the calculation for the bow thruster,
it came out at about half the size of that for a 34feet surface
boat. This mainly due to the lack of above water surface for
the wind to push against. I look forward getting some data
once the hull is finished. Also, as you said, when I did the
calculations for electric motor and batteries require for
submerged travel, found if the speed is kept low (under 2knots),
then I can reach the 30mile range requirement with very few
batteries. I think a 200mile submerged range could be realistic.

Do you have much data from the proto-type and submerged power
requirements? Since there will have the same hull shape and
ratio, I might able to calculate an appropriate constant for
this hull type which can be applied to calculating the power
requirements for the 200ton. Speed, power, energy used, etc..

Also, according to my bank I should have no problems making a
wire transfer to .....


Hello Ian,

It might be a good idea to start with 200 tons - sell it and go for a 450 tonner later.

I have got your picture - this was exactly i had in mind with the saddletank in whaleback form.

I would not be concerned about the sleek look of the 4:1 shape. The impression of the hull when it is done and you see it, is very "yachty" - i was quite surprised about how "yachty" and sleek the look is with the prototype. 3D rendering gives you a certain idea of the impression but can not give the full picture.

This must be the reason why car builders still work with 1:1 clay models to evaluate shape. It is also a very good method to draw it in sand and have a cross section 1:1 with cheep material like plastic tubes styrofoam and similar - shipyards and airplain builders do so.

I see no problem to integrate a thruster tunnel into the tail section, the fin, or a saddletank hump, similar to the front hump. If you put a front hump it would be good to have a similar size hump in aft section with similar force arms to enable a emergency blow out and lift on even keel.

I get from your mail that you are equipped with modeling software for thruster size - i am not surprised by the fact that the needed thruster is a small one - i am more surprised by the fact that the software predicts this as i assume it was not meant for subs. I found that the prototype hull always reacted to forces of about 1kp as long as applied steadyly - even in storm conditions. So i would assume that your boat 10 times bigger in mass should be fine with a force of 10kp - given the surface volume ratio probably even less. So i expect it to be handleable by a single person pulling a line, manouverable by a electric outboard of standard size, towable by a dinghy size boat, bringing a maximum of 10kp force to the anchor rig in extreme storm conditions.

Yes, a submerged 200 miles range is realistic - If invisibility from surface is important to you i would check aluminium batteries as secondary propulsion method they are energy dense non toxic easy handle, affordable.

My prefered version for simple, safe, silent, unlimited range, and low cost, ist the tandem.

On my prototype machinery was first a 200 watt electric motor - to drive it i had 2 batteries i could easy handle to take them out at the end of the day. (70 AH camping version). I later started loading them on board with a small honda generator - as loading of any lead battery needs 10 hours this really sucks so i used the generator for snokeling - later i attached a 50m hose to enable snorkel mode at diving depth. This worked fine. Then i thought - and if i let the generator in the dinghy bring electricity down with a cable and pull the dinghi behind the sub - this did not only work perfectly it was also silent, no gas hazard, unlimited range, the dinghi was always on hand to go for a trip on shore - so for me the best version of all was to get rid of all battery and exhaust gas in the sub and go with a tandem version. The only bad point for tandem is that you are still visible from surface which is a NO NO for a military sub - but can be an advantage for a yacht sub - you can make GPS, Compass and camara work in the tandem - so still keep your eyes on suface still maintain radio and navigation of a surface ship.

The best models for submerged cruising power requirements and speed are the energetics models of whales. Have a look at ( and ( to see the general idea.

For a whale energetics is (14 kg of fuel/day) cruising (95km/day) with an "engine" that "eats" 589g/diesel/hour. Where only half of this engergy is available for locomotion - other half is for life support.

So my general propulsion suggestion is: find the smallest and most economic diesel you can find, make sure that it will not consume more than 1 liter of diesel per hour (24 liter a day) this will leave you with a propulsion energy of 3 HP (a submarine diesel is rated at 200g/hp/hr) - so most suitable would be a 10HP diesel at 1/3 throttle - optimize propeller for 6 knots of cruising speed. This will give you a very similar range, efficency, speed, and locomotion cost, as the whale model has.

If you can transfer to .... this would be great i just need a paper that states what the money is for and who is sending it, and i need to report the incomming transfer before it comes otherwise it would be rejected. So no mayor problem on this.

I also scanned colombian law texts for problematic passages concerning "submarines" i found that all texts are talking about ships and "naval artefacts" categorizing for military, commercial, passenger transport and private use. So finally we slip in here as "naval artefact for private use" - which is yacht - no extra complication for "submersible". There are also no legal problems arising from a 200ton displacement. It is all in the hand of one entity called DIMAR from building to licencing this entity (close to navy) also has the formal obligation to "promote research ocean investigation and shipbuilding progess" in colombia - looks that we can use some of this in our advantage and go just trough the front door with our projekt.

What concerns building contract i would suggest to keep it short simple and clear. I would suggest the following.

Building contract.

Ian .................... identified ................................... (Owner)
Wilfried Ellmer identified .................................... (Builder)

Naval Artefact (yacht) 18m x 4,6m displacement 200 tons.

Value: USD ...........

Payment: (50% building start / 50% hand over) bank transfer to .... account....

Building Site: colombia Santa Marta (or according to agreement)
Building Start: 30 October 2007
Handover date: 30 October 2008

Contract includes:
Hull building, impermeabilisation, integration and function of Rudder, Snorkels, Diesel Engine, Viewports. Getting Hull ready for sea trials, sea trials including shallow dives and including transfer to california (hand over site), pilot training for the owner in california. Fixing of problems that may arise in sea trials.

Contract does not include:
Cost of the acrylic viewports, cost of the engine, other equipment, cost of panama canal and diesel for the transfer, hotel cost during pilot training.


Signature: Owner

Signature: Builder

Let me hear your thoughts...

Cheers, Wil

Hello Ian,

Got your copy of passport and driver licence today.

Thanks a lot

Cheers, Wil

Hi Wilfried,

I agree, start with 200tons, sell it and upgrade is probably a
better idea. I'm hoping to go through a few subs before I'm finished.

I'll definately be doing more 1:1 mock ups as I figure out more
about how the interior will be layed out.

Bow thruster calculations. I just used standard calculations I
found on the internet. Calculate the above water area of the
vessel that can be caught by the wind, select a wind speed,
the distance from the vessels pivot point. Plug it into to the
formula and you get an estimate of the thruster power you need.
This can be taken a step farther, and calculate how fast you
would like to sub to rotate using the bow/stern thrusters.

Batteries. I've been following metal air batteries for a few
years. Some of my early submarine designs used Aluminum air
or Zinc air batteries. Although development is progressing,
more so recently, I cannot find any metal air batteries which
could be bought off the self. Although this may change by
time I take possesion of the sub, for the time being I will
design around using lead acid batteries (and plan on dealing
will their down sides as well, hydrogen off gas, long recharge
times, etc.).

I want to avoid towing something on the surface while dived
to minumize chances of entanglement. Use of snorkle would be
possible while travelling close to the surface.

I'm pretty happy with the nose, but I'm still trying different
configurations for the tail and a stern tank. I quite like it
with just the nose tank and no stern tank, but some sort of
structure towards the stern will make it much easier to get
on and off the sub if the water isn't so calm. Of course, I'll
be tweaking the design and placement right up until they are
bolted onto the hull.

Questions about the contract:

- Shallow test dive. Will the sub be consider tested for a 50M
operation depth on delivery?

- Diesel engine. Does the contract price cover the cost of the
provisional diesel used for testing and delivery?

- Can you supply viewports? If you can't or I choose to fit
these myself after delivery, how are the viewport holes plugged?

As for date of the payment, it's looking like the funds from the
sale of the company I work for will not be deposited in my
bank account until the end of September/early October, several
weeks later than I was expecting. I will look into what I can
do to expidite this and also alternative ways I can raise the
funds for the deposit.

My main concern is that somebody else places a deposit first
and I have to wait 2 years before getting my hull.


Hello Ian

I am speaking of shallow test dives because of the practical limitations of test diving. First of all a guaranteed operation depth of 50m requires a test dive of 100m better 150m.

This is no problem for hullstrength in general. But it is a problem for practical ejecution. If anything goes wrong - for example a cable breaks or a weight drop mechanism fails the hull is at 150m depth where it can not be accessed by scuba divers. To get just a hook of a crane connected for recovery you need a saturation dive ship which will cost you - for just one day of operation - a sum that is higher than building cost. To lift a boat of 200tons you need a mega crane which will cost you another sum way above building cost.

So to keep financial risks at a reasonable level you should go for testing in scuba diver range to maintain the possibility of relativly easy recovery in case something goes wrong.

For several reasons i also plan to stay on board during testing to see when a viewport starts to crack - a ball valve or a o-ring starts to filter, etc...So the possibility to escape in case of mayor malfunction is also a personal concern for me. I will personally test it to "escape still possible depth" - I will also stop testing as soon as any component should show any sign of stress like viewport extruding perceptible, a crack in one of the viewports, filtering in packings or sound frequence changes when hit with the hammer compared to surface.

So the limit for testing is not the strength of the hull but the cost of possible recovery this cost of course goes up with boat weight. So as long as we can not budget hull loss and recovery cost as part of the "learning process" we should keep anything shallow which basicly means no testing out of scuba range.

When we test in scuba range - the decision how close you will finally "operate" the boat to the tested limits is basicly your decision. It is also your decision how far you are willing to risk your investment to push the test limits and in consequence the operation limits deeper than scuba range.

At the moment all i can say is - most probable hull destruction if i had to bet my money on a certain depth it would be at 1200m (if the hull contains no viewports). Having a viewport configuration as you plan it - the hull weakening is about half so i would bet for hull destruction at 600m for the particular hull you plan. I see concrete hulls in offshore industry operating at 300m at the moment so - as long as your viewports can take it you could push it to 500m test depth - which means 166-250m operation depth for the viewport configuration you plan.
You could go to 400-600m operation depth if you change viewports by a camara sistem that would not create hull weakening.

All this is pure hull calculation that leaves apart all other components. In any case the viewports are the weakest component. You can not make them "incrediby thick" because combined with the thick walls of the hull you would get a kind of "tunnel view". So to keep the ports in a range where cost of ports and window geometry are still reasonable you should go with something that has a similar geometry as the kittrige sub ports have - just a size bigger. In any case ports of such geometry are rated for some 100m. So a reasonable window geometry is another factor that limits the dive depth to scuba limits - beside practical testing.

Viewports for a submarine should bring a ASME PVHO-1 stamp to guarantee this depth rate. Problem is - they will cost a factor 20 more if they bring this stamp. If you skip this stamp and buy acrylic discs in a decorative item shop you get them a factor 20 cheaper they come probably from the same production line - hold probably the same depth - but miss the stamp so no guarantee on that - i am personally willing to give them credit in a manned test dive to some 1/3 what ASME PVHO-1 ports would guarantee. Which brings us back to a shallow 30m test dive with a still calm builder within escape depth, checking filterings and crackings of viewports by hand - surviving in case of catastrophic failure, and recovering the boat at a reasonable cost later.

If you buy ASME PVHO-1 stamped ports with 150m rating i am willing to push a extreme test dive down to 150m as i am sure that the hull can take it and a viewport failure in the process is reasonably excluded.

What depth the boat is dived at handover depends most of all on the viewports you are willing to provide as they are the most probable failure point.

I am not very happy if the contract makes me taking over "general guarantees" for components i do not build and which are not under my control like the viewports.

You see your question for a "operational depth at hand over" is a question that needs to be anserwed with care as lawyer questions come in here.

I will not hand over a "operational submarine" anyhow and the tecnical safety limits of the sistem will depend on the components you build in later - starting with the viewports.

At the day i hand over, the components the boat contain at this moment, will be tested to scuba range 30m for the reasons explained. In general i would recommend to keep it in this range especially if you have no ASME PVHO-1 stamped ports which would be a mayor cost factor.

To be on the safe side of recommended submarine operation you should take a 90m testdive (unmanned) to operate safely at 30-45m.

This 90m or more - test dive is a risk i am not willing to shoulder - especially as long i have not seen nor made a destruction test on a viewport of the same series the boat has - as long as such results are not available - keep it shallow and take nothing for guaranteed that goes below the already tested 30m.

Testing out a actual viewport is a good base to come to a final deep testing and operating depth.

As i see the viewports a critical component as well from cost as from security point of view i would prefer if you could provide them to the construction site or even better put them in later.

I would plugg the viewports holes with equal sized discs of reenforced concrete mounted in with silicone - you just pull them out and replace with acrylics of your choice later.

The diesel engine is not included in contract as the cost of a diesel depends much on what you want to build in, a fine yacht diesel sold new for this purpose can cost 10 times the money a refurbished diesel from a tractor or a construction engine can cost - but is basicly the same.
You can send a diesel of your choice to the construction site and we build it in. Or we can opt for a provisorial diesel (refurbished) which will work for the hand over trip. I can get one for 1500 USD so this will not be a mayor cost factor.

I can get viewports in Colombia but the factories are in Europe, USA and Japan, so this is import stuff and more expensive here as they would be in California.

There will probably be no problem when you fund your Project in October.

Cheers, Wil

Hi Wilfried,

So 30m test depth on delivery, this is fine. I will figure out
some way to minimumize my risk testing it to deeper operational
depths. My current thoughts are 250m being the maximum operational
depth (tested to 500m), but this could endup being much less
(150m maybe, tested to 300m). Testing will be a big job.

Viewports. Plugged viewport holes will probably be the way to
go for delivery. The viewport details are still being worked
out, I'm approaching several companies for a quote. If i do
not buy PVHO-1 stamped viewports, I will follow PVHO-1 proceedures
(as layed out by Dr Stachiw) for shrinking and annealing. Also
there is a big chance I will go with smaller viewports once
I have some quotes for 1meter acrylic disks.

How are the viewports housed/framed on the sub hull? Are they
similar to a steel vessel where there is a metal window frame
that seats the acrylic? Or having you taken another approach?

I will probably go with a provisional diesel brought in
Columbia. I would use the information gathered from operation
with the provisional engine to choose a suitable diesel engine
once in California. Best case is that I decide that the
provisional engine is prefect and either leave it in or
replace it with a similar engine (but quieter).


Hello Ian,

Ok test depth on delivery can be 30m. I will have to run a 1:1 test of the viewport plugs. In general PVHO-1 recommended proceedures are the standard production procedures in acrylic manufacturing so i would assume that shrinking and annealing is part of this anyhow.

The problem i see at the moment is that the stamp and especially ABS certification requires the presence of an INSPECTOR who documents those things. Marlin Submarines "Alicia" had a 6foot acrylic sphere rejected by such a inspector because it had a little bubble. Problem is that the cost of the inspector might be higher than the material cost.

The flatness of the mounting is critical to avoid cracking. If you have a steelskin over ribbs you have a lot of movement and bending during dive - the frame is necessary to provide a stiff mounting free of bending.

In a concrete hull there is no movement during dive. A mounting formed in concrete provides a perfectly flat mounting under any load. Steel rings with concrete might form stress points in the hull. So i prefer direct mounting on concrete with a silicone filled gap around the port this works similar as the O-ring but provides more security against pop out under internal overpressure and leaves a reasonable movement (temperature changes) between hull and port. - worked very well in the prototype.

Certainly a good decision to work with a provisorial diesel this allows a lot of options including maintain this diesel or use it as a back up.

Cheers, Wil

Hi Wilfried,

thanks for answering my questions and the ASME PVHO viewport paper.

I was thinking that to stay closest to the parameters of Dr Stachiw's
research, placing the acrylic in a metal housing would be a good idea.
I can see that for flat acrylic disks it probably won't make much
difference between seating them in a metal seat with an O-ring
compared to a concrete seat with a silicone gasket. But I'm also
considered a spherical sector window with a square edge for the
front viewport. I think this would require a metal seat so that
both edges of the of the viewport can press against a surface.

If the metal seats where attached to the concrete hull in the same
manner you described for attaching the acrylic viewports (i.e.
using silicone), I don't think there would be any additional
stress on the concrete hull.

I would consider it important to have a retaining ring that is
attached with hull with some kind of fastener over the viewports.
This is to prevent loosing a viewport in the case over pressurization.
If the acrylic was to break free of the silicone, the retaining
ring would prevent the complete loss of the viewport. If the
viewport didn't resit correctly after an overpressurization event,
it would still be more effective compared to completely loosing the

Current thoughts on viewports are to reduce the size of the side
viewports to 50cm diameter and use flat acrylic disks. For the
front viewport, keep it at 1meter diameter, but use a spherical
sector window with square edges (probably a 90degree sector).
Other than the front viewport which goes up in price, this would
mean a cost reduction, but also I can drastically increase the
safety factors of the viewports so there predicted failure
pressure is high that the estimates for the concrete hull.

I've attach another pic of the hull. Playing with the sail a
little bit, this time trying a sedan type sail rather than a
foil type sail. Partly because a sedan type sail has a lower
drag (and windage) than a foil, but also for aesthetics as well.
I'm sure we both want the sub to look great when it's finished.

How are the hatches attacted to the hull? Do they have a
metal ring, or is it the same as you describe for the viewports?

A slight side line to the submarine. Have you looked into
building a large concrete pressure testing chamber that could
easily fit the submarine we are discussing? How much would
it cost to build? I think the ability to be able to pressure
test (some to destruction) large submarines on land would
be a major plus to the concrete submarine industry.
Destruction testing concrete hulls in the ocean will be very
expensive, but on land it would cost little more the price
of manufacturing the hull.


Hello Ian,

- placing viewports in a metal housing -

The viewport mountings with retaining rings and machined seatings are not solutions that you would see in a building that is meant for exposure to saltwater over long periods of time.

It is ok for a pressure vessel that stands on land like a diver chamber or for a small sub with a mothership that comes out of water on a dayly base - and this is what those solutions finally where developed for.

I would not trust any bolting, mechanical device, made of steel after a year in saltwater. Steel in saltwater is steel under a very careful applied multi layer of high quality paint.

Any steel that can not be painted is not meant to stay nor survive nor work in saltwater ambients.

So for me steel seatings rings and worse exposed retaining rings and screws is to import steel corrosion troubles to a project that is designed to get rid of this kind of trouble - and what is worst - with no real benefit. In fact you can trust silicone in saltwater to maintain your port in place after a couple of years - but a screw you can not.

I tested a lot on this and finally concluded that the vision of poping out viewports is not likly to happen. If you test it you see that a overpressure build up capeable to pop a silicone mounted port out would destroy the hull and kill you in the process anyway.

What you should keep from PVHO1 and Stachiw is the mount area size the port geometry, the principle that the port must lay FLAT in a absolute stiff ambient, and the priciple that water tightness can be achived on peripherical of the port. Also no boring, groves etc in the port.

The other reason why i did not use steel mounting rings in the prototype is that i found in my testing that the combination of concrete hull plus steel rings tend to fail earlier than concrete only. - I assume that this has to do something with stress build up between those elements.

You also can replace the concrete plug disks with mountings you are comfortable with - just let me know the size of the plug holes. In any case i am confident you will be more comfortable with my simple solution when you see it and tried to pull one of the plugs out.

In general i recomend to have only one type of viewport so testing out one port and mounting gives you a conclusive anwer for the whole boat. In my prototype even the hatch had the same mounting as the viewports.

A 50cm flat port gives you a view that includes the whole field of vision when you sit in front - so i see no real need for bigger ports...

I have no experience with sector windows - i assume that they bring tension forces to their mounting other than flat disk ports - so a steel mounting may be indicated.

In the nose area I can provide you a 1m flange area similar to carstens boat to put a sector front port together with a steel mounting (screws inside the boat). As located in nose area force distribution should be fine. You could also go to the extreme to have a acrylic nose similar to alicia - no problem with the mounting - just a cost problem.

-hatch- on the prototype i had a acrylic hatch - but i would change this for burglar reasons. So we might go for a massive steel hatch to discourage burglar intents.

Concrete pressure chambers would need pre-tension in the rebar - and would not hold a lot of internal pressure anyhow - steel is better here. But the cost asociated to move a 200 ton boat around and into a giant pressure chamber is prohibitive anyhow - it is by far cheaper to risk a finished hull in open water testing.

...i did not get the attachment of the new sail version...

Cheers Wil

Hi Wilfried,

sorry, I forgot to do the "attach file" step before I sent the message.
I have remembered to do it this time. Still work in progress, but I like
the direction the sail is taking. Also included is the rear saddle tank.

Good point about corrosion, I'm trying to research what is avaliable
in the way of corrosion resistant fasteners that can attach to concrete.
Do you have any pointers or recomendations for this?

I'm interested in how the tail is attached to the hull. Also, how
do you recommend attaching the forward/after ballast tanks, the
deck and sail to the hull?

Metal hatches sound the way to go. Also I will research corrosion
resistant alternatives that might be used for a viewport retainers and
other perminintly submerged external parts. I was planning on
using GRP/FRP for the fore/aft external ballast tanks.


Hello Ian,

I got your images, yes the sail and saddle tank area can look like this. All attachments like tanks and tail will be connected over rebar anchors so that the tension forces are not taken by any "connection element" but by the structural rebar directly. In fact those parts are not really "attachments" but part of the forming process. Anyhow you can connect additional parts later. You would just hammer the concrete out what is not difficult as those parts are relativly thin walled with a consistancy similar to a brick wall. You then can solder flanges to the exposed rebar to make a bomb prove connection to GRP, or other materials you want to build with. Just make sure that rebar gets covered again and do not stay exposed.

I would like to hand over a boat with a saddletank and sail configuration in concrete - it can look exactly as in your pictures - i can form that - i would suggest smoother transitions between central, front and aft saddletanks and less "edgy" design for the standing area - for drag reasons.

Can i publish some of the conversation we have here on my website ( - it would be of interest for future projects...

Cheers Wil

Hi Wilfried,

I was also thinking that the ballast tanks and sail could be done
in concrete. These would be made seperately and attached to the
pressure hull using the mount points discussed in the last email?
Having the ballast tanks and sail completed on delivery certainly
gives me a head start on fitting out the submarine. I probably
wouldn't even start on the ballast tanks until I took delivery
of the submarine to make sure I got the curves right.

I would like the final submarine to highly configurable, where it
could be reconfigured for different tasks. This may involve
having several different sails, one with an ROV and small item
recovery capability, one with environmental monitoring and
sample capability, one with media capability (powerful lights
and cameras), one that just looks sleek and "sexy", etc..

Thanks for you description of the external attachment points for
the hull. Give me a clear imagine of how this is going to work.
For internal attachments, things like walls, chairs, equipment
(air tanks, O2 tanks, generator, etc), is the same process used?

Yes, feel free to publish any parts of our conversation that
people might find useful.

Also, the ...... deal closed last week, bring me a
step close to providing the funds for the this project. One
more minor round paper work, then I should having the funds
in a couple of weeks (according to my companies legal dept.).


Hello Ian,

I like the modular sail configuration idea. I can make a couple of fixation points for the modules.

A ROV is not necessaryly limited to small item recovery - you can manage a lift bag with ROV only and tow the item home.
The recovey on CENTRAL AMERICA was done by ROV only.

For internal attachments you can just use drillholes and concrete screws from the hardware store.
The weakening of the hull is insignificant and screws are not exposed to saltwater.

You should have a couple of drilled fixation points where you can fix the structural wood or metal pieces similar as panel installation in a building.

Thanks for your permission to publish parts of our conversation.


Hello Wilfried!

I have the monye to fund a 200ton concrete submarine in my bank
account now.

So, let's sign the contract, make transfer for the deposit and
start this adventure!

I guess the first thing to do (after contract/deposit) is to
set out a time line. This should give me an idea of what to
plan for an when (thru-hulls, final viewport sizes, etc).

Anyway, I'm very excited to be doing this!


Hello Ian,

I am ready to go !

My timeline is 4 weeks to get the permissions and building site in place.

Then i plan for forming and building progress in a range of 1ton/day
Which leaves us with 7 month raw building time - the rest is sea trial and hand over.

First thing i need from you is the building contract - if it is ok with you we can go with the text
sent earlier - i just need it signed in english and i need a spanish version (signed too) to present it
before the bank and the ministy of external relations to define and legalize finance flow.

With this i will open an account dedicated exclusivly to the project (at ....). The paperwork
must be done before the account can be enabled to recive funding. (The building contract is base of it).

So please check the text and send me a final signed version (can be scanned by e-mail) if possible a spanish version would be fine but if it comes english only i will traduce and resend for sign.

Lets start this adventure!

Cheers, Wil

Hi Wil,
the contract we already discussed is find with me. The text is below
with a couple of minor changes (think all changes where just syntax).
One thing I would like to clarify in the contract is in the not included
section, for "other equipment", I'm assuming that this is generators,
batteries, electric motor, sonar, life support, etc. (as opposed to
"valve for diesel exhaust, steering wheel for rudder"). If have that
correct, I would like to include examples of what is not included, i.e.:
"cost of the engine, other equipment (such as, generators, batteries,
electric motor, sonar, life support, etc.)"
Hi Wil,
the contract we already discussed is fine with me. The text is below
with a couple of minor changes (think all changes where just syntax).
One thing I would like to clarify in the contract is in the not included
section, for "other equipment", I'm assuming that this is generators,
batteries, electric motor, sonar, life support, etc. (as opposed to
"valve for diesel exhaust, steering wheel for rudder"). If have that
correct, I would like to include examples of what is not included, i.e.:
"cost of the engine, other equipment (such as, generators, batteries,
electric motor, sonar, life support, etc.)"

Contrato de construccion entre:

Ian .................................................. (Dueño)
Wilfried Ellmer .............................(constructor)

Artefacto Naval 18m x 4.6m desplacamiento 200 toneladas.

Valor: ...................
Pago: 50% en el comienzo 50% en la entrega en transferencia a la cuenta correspondiente de .....

Sitio de construccion:
Santa Marta Colombia

Fecha de inicio : 30 octubre 2007
Fecha de entrega: 30 octubre 2008

El contrato incluye:
construccion del casco, impermeabilisazion, integracion y funcion del timon, snorkel, la instalacion del motor diesel, y los cierres provisoriales de los ventanas.

Terminacion del casco para prubas de mar, las prubas de mar incluyendo prueba de submersion.

Traslado a california (sito de entrega) entrenamiento de piloto para el dueño en california.
Reparacion de problemas cuales pueden emerger en las pruebas de mar.

El contrato no incluye:

Costo de ventanas acrylicas, el costo del motor diesel, demas equipo, costo del tickete para el canal de panama, el costo del combustible para el transfer, el costo del hotel durante el entrenamiento en california.

Firma Dueño: Firma Constructor:


The contract includes sea trials and a hand over trip - so i have to equip the hull with all the items necessary to perform such a trip. It must include snorkel valves as a trip without such valves would not work - it must include things like a working hatch, a working cooling sistem for the engine, a working rudder including a wheel to perform sea trial and trip. A "generator" and a "battery" is part of the engine anyhow - it would not start without one. Also a basic electric sistem with basic nav lights. So will be a basic emergency blow out sistem (chemical) and a basic diving sistem (tank and pump). (we could not perform the test dive without one) and a basic ventilation sistem. When i say basic it means that this sistems will do their job but still be loud, clumpsy, so you might go later to more sophisticated ones.

What is not necessary for the hand over trip is a electric motor, (with a huge battery block), sonar, life support gas management, electronics equipment, uw communication, nav sat, kitchen equipment, luxury toilet, sound equipment, ROV, camara, etc...

So without going trough each item and its details we can just define boat funcion: We will do the hand over trip, and we will do it safe and anything to do so will be on board. Everything that is not stricktly necessary for the trip will not be on board. It will be a empty hull in transfer more than a fully equipped submarine filled with "sub stuff". But it will navigate and dive well, my life on hand over trip depends on that.

hope i have answered your questions - let me know if some left.

Above the spanish translation - i need you to transfer the text to a paper document and sign it and send it to me as an attachment so i can print it and sign it too - as base document for the account opening.

Cheers Wil

Hi Wil,

Please find attached to this email a pdf format version of the signed

Thanks for answering my question, I think I might have worded it badly.
I was basically asking, does the "parts include in the hull price" include
things like snorkel valves, and other minor items that would be need
to sail the sub to California (or would I get a bill I wasn't expecting
for those items later). I'm just trying predict all my costs up front
to help budget for other items (like viewport acrylic, batteries, comm.
equipment, etc).


Hello Ian,

No, there is no "small print text" in my contracts. The 50% funding will be good to bring the sub in a seaworthy state and sail it up to california.

Only "extra" is engine cost (1500 USD), the panama canal ticket, and diesel for the trip.

So what concerns funding the first 50% brings the artefact to your door, the second 50% is your OK to a well done hand over of a hull that meets all specifications agreed.

I am just trying to keep the hull building and the "other" costs apart to keep things cristal clear in budget and funding.

No extra lists for tools, shadow roof needed, equipment etc..., - all this is included in the funding.

I understand the need of having clearness about that upfront. So the calculation is one 50% payment to come to hand over and nothing else to worry about.

The hull will NOT come with a "extra to pay item list". Nor with a "special items not included in original agreement list" It will come as it is (a seaworthy but barren hull). At the price that was agreed in a short and clear contract.

I have to watch a serious business image and can not afford "small text" or "unclear" agreements.

In the attachment i send you is the documentation of the paperwork done so far.

With the contract you sent to me at 24.sept i went to .... next day and opened a project account.

The account Nr. is ........ Account Holder ........ The account is exclusivly dedicated to the project as described in the contract.

The Bank accepted the contract and the documentation you sent to me as a base for the account opening and reason for international money flow. So i think we are fine with documentation so far.

The project account is still not operational as my personal data will be checked by the bank in the process. This include fingerprints, identiy checks, cedit check, visa status, etc... If they find all OK they will release the account. This should be trough in less then a week.

The project account will then be ready for funding - funding must be announced then before wired otherwise it would be rejected.

Once funding is up i have to present the project to local authorities (mayor) in Santa Marta (i will use the contract and bank data as base for this to present a "foreign naval investment bringing work to the area...")

They will give their point of view and pass it to DIMAR - process which will end with the asignment of a final building place including ambiental and labour permits.

The plan is to be ready with paperwork and start casting concrete end of october.

Hello Ian,

uups - i did not send the attachment - so here it is...

it looks like you have a neighbour in california with similar this mail today...




Hi Wil,
thanks for clarifying the lack of "small print text", sounds great.
I didn't find any documents attached to the previous email.
Let me know when the account is active, I will have my bank wire the
first 50% to your ..... account.

Hello Ian,

The conctract was accepted as reason for international money transfer, all personal data is checked and veryfied.

The project bank account is in place and active.

The account details:

So we can start this Project right away.



When they are avaliable, I would like the data points/dimensions
from the the frame table so I can enter the data into my CAD
program for layout and modeling purposes.


Hello Ian,

I am currently working on the table - the task is to adapt the frames from the 25m boat (see attachment)to a 18m boat. It is change of scale not more.
The points in the drawing are for inner diameter - The wall thickness must keep the same diameter/thickness ratio over the whole hull so it will be equally pressure resistant in all parts.

The drawing gives hull points at distances of 3m. The hullpoints in the drawing will be just \"straightened out\" between the fixed points to have perfect flowing hull lines.

If you take the points of the drawing scale and straighten the lines the frame table in your program will be exact in millimeter range and represent the hull perfectly.

I will send you my version of the table (Excel) (inner and outer diameter) in the next 3 days.


Excellent! I'm excited to be a part of this.

I've attached an 2D diagram of what the sub looks like based off of
the figures you supplied me. This looks pretty close to the diagrams
your have on your website, let me know what you think.


12 october
Hello Ian,

Got your drawing. Yes this is the shape as at the website, adapted to 200 ton / 18m It is the same shape as the prototype has.

One of the first things i will do on building place is to establish centerline with a wire.

All construction will be referenced to that centerline. To establish locations exactly you just have to describe the centerline position for example: the hatch has its center point at location 10800 (from bow in mm)

This allows to organize your computer model and the building site in a very similar way. So all measures and renderings you get from your model will reflect exactly the situation at the construction site.

The Mayors planning secretary in Santa Marta promised me a response about building site for tueseday - there is a Vice President visit today and elections for 28 of October so we have to push a little to get their full attention...

I am checking on broadband internet solutions in the area as i want internet in place when i move to Santa Marta.

Very exited to build this for you. I am sure we will establish a new yachting segment with this project.


Hello Ian,

This has been a very productive week to get things in place.

I have been calling DIMAR in Bogota to check on the permission for the construction and was referenced to the office of ...... who is the office chief of division "Gente de Mar y Naves" (seamen profession and ships) in DIMAR headquaters and the direct responsible person for all ship construction permits in colombia.

He invited me to come to DIMAR headquaters and chat about the matter. So i took the 6 hours travel to bogota the next day (at 18.oct) and walked directly into that office at 11 o clock.

I presented him the fotos of the website, the basic plans of the project, the timeline etc.


So all in all building a submarine yacht gets us kind of automatic goodwill in the absolute highest spheres of DIMAR.

The tecnical process of permit is, that the paper will come to the desk of ...... who is ingineer will give his concept and needs a final OK from the admiral - in words of ......the permit is - NO PROBLEM - kind of routine.

What we need to make this formal and get it stamped is nailing down a final building site. To move this point forward ..... gave me a list of shipyards authorized by DIMAR.

In this list there is no authorized yard in Santa Martha, it looks like as the process of getting all shipyards under strict DIMAR control is somewhere halfway and there are yards working with and without a permit of function from DIMAR.

Given the proyect we should stay as close as possible to DIMAR. So for me Santa Martha as building place is off and cartagena especially the sector of Manga where a whole series of DIMAR approved shipyards is situated came into focus.


A yard of the DIMAR yardlist is ... .... We talked to to the heads of the yard which are ... ... they showed particular interest in being involved into a new shipbuilding tecnology and offered a building site with 4m water depth (sufficient for the project) a office and store facility as well as yard personal at a very reasonable price.

This seems to be a shipyard that is willing to give us control over the whole yard so they can go to do less and less fishing boats and more and more submarine yachts over time - a option i would like to go for.

Another option might be .... which is the official shipyard of the colombian navy - maybe they find a place to take us in with the project. Building in this yard in the shadow of navy warships would be nice due to security features and it would make our project almost a "official colombian navy proyect".

What comes up next is a trip to cartagena where we already have set dates to visit the yards and close contracts for thursday next week. I will give you a detailed picture from the finally choosen building site with digital fotos.

If all goes well (and i expect so) we will start forming the hull as soon as 1.of November. All backed with permit from DIMAR and in a official authorized shipyard.

At the moment all is going well, we are ahead of shedule - doors are opening quickly we get connected and are on our way to walk our project successfuly right trough the frontdoor.



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