# Weight Estimate

Discussion in 'Boat Design' started by Farley, Apr 15, 2011.

1. Joined: Jan 2011
Posts: 15
Likes: 0, Points: 0, Legacy Rep: 10
Location: Austria

### FarleyJunior Member

Does anyone have any data on the weight components of a 30m monohull?

the weight estime is a relatively important factor to a good design and the one i have done is down 18 tonnes!

the vessel is going to be a research vessel, monohull, 10 persons on board. aluminium construction.

the structure i have calculated but i know little about more random facets that make up a boat such as the electrics. all i could find was this

Thanks for any help offered

#### Attached Files:

• ###### Screen shot 2011-04-15 at 10.01.29.png
File size:
59.5 KB
Views:
816
2. Joined: May 2004
Posts: 5,373
Likes: 247, Points: 73, Legacy Rep: 3380
Location: Italy (Garda Lake) and Croatia (Istria)

### daiquiriEngineering and Design

3. Joined: Oct 2008
Posts: 6,644
Likes: 650, Points: 113, Legacy Rep: 2488
Location: Japan

### Ad HocNaval Architect

Indeed it is. It forms the whole design whether it shall succeed or fail.

However, you need to be a bit more specific....what type of 30m monohull...L/B ratio plays a part...as does speed...so does which rules and regulations....payload....what is the SOR etc etc. Otherwise it is like comparing a mini with a ferrari..they both have 4 wheels, both are cars both carry passengers etc....

This "simple" mono hull, of 30m LOA has the following:

Group 1 Hull = 24 tonne
Group 2 Propulsion = 10 tonne
Group 3 Electrics = 4 tonne
Group 4 Comm. & Control = 1 tonne
Group 5 Aux. Systems = 6 tonne
Group 6 Outfit = 8 tonne
Group 8 Fluids = 0.5 tonne

Margin 5% = 2.5 tonne

So the total lightship is around 55 tonne.

This is for a mono of L/B =5
Top speed 25 knots
Carrying 35 tonne cargo.

This might help..

But you wont get too many weight sheets available publically.

4. Joined: Jan 2011
Posts: 15
Likes: 0, Points: 0, Legacy Rep: 10
Location: Austria

### FarleyJunior Member

research monohull, specs are
LOA = 30
BOA = 6.7
Tc = 1.8
top speed = 20 knots
displacement = 123 tonnes.
Aluminum hull and superstructure
IMO and SSC

5. Joined: Oct 2008
Posts: 6,644
Likes: 650, Points: 113, Legacy Rep: 2488
Location: Japan

### Ad HocNaval Architect

The figures i quoted above the full load is 120tonne, so similar to your 123 tonne.

Big differnece is the machinary...more than double...so that can't be correct!...and a crazy amount of fuel too.

Otherwise rest is not far off.

6. Joined: May 2004
Posts: 5,373
Likes: 247, Points: 73, Legacy Rep: 3380
Location: Italy (Garda Lake) and Croatia (Istria)

### daiquiriEngineering and Design

I'm sorry, didn't read your post correctly. You were actually asking for a weight breakdown, while the links above give only total operative weight of different ships. My fault

7. Joined: May 2004
Posts: 39
Likes: 1, Points: 0, Legacy Rep: 10
Location: South Africa

### Kobus PotgieterNaval Architect

Just done a design now and completed the construction of a 30m Patrol ALU boat.
view www.navaldesign.co.za
They weight (Full displacement) came in at 110 T.

8. Joined: Oct 2009
Posts: 4,746
Likes: 337, Points: 83, Legacy Rep: 1485
Location: Midcoast Maine

### DCockeySenior Member

Are you a student?

9. Joined: May 2009
Posts: 16,654
Likes: 326, Points: 93, Legacy Rep: 1362
Location: Cocoa, Florida

### Doug LordFlight Ready

=======
Yes, he is:

22-2011, 07:41 AM
Farley
Junior Member Join Date: Jan 2011
Rep: 10 Posts: 15
Location: Austria

I have been set the task of analysing a sailing yacht's keel using a program my lecturer has made ( it uses ISO 12215)

For this I need information about a specfice model/yacht's keel configuration.

10. Joined: Aug 2002
Posts: 14,598
Likes: 708, Points: 123, Legacy Rep: 2031
Location: Milwaukee, WI

### gonzoSenior Member

It can be anything. What you have to do, is list every component, including accessories, water, fuel, etc. and add it all up.

11. Joined: Mar 2011
Posts: 9
Likes: 0, Points: 0, Legacy Rep: 10
Location: Viet Nam

### starichJunior Member

Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.