Stability question

Discussion in 'Boat Design' started by DavidT03, May 21, 2011.

1. Joined: May 2011
Posts: 10
Likes: 0, Points: 0, Legacy Rep: -21
Location: UK, Scotland

DavidT03Junior Member

Well im now at the stage of doing my stability calculations for my project and my first hurdle is finding my new center of gravity.

I have the original details on my ships stability below. Please note im calculating it on the light ship loading condition

Im adding 89.24 tonnes on each side evenly so a total of 178.48 tonnes will be added to the ship.

So basically im wondering how i would go about calculating it and is there a simple way as im adding equal weights on each side?

Also please let me no if any other information is required and il post it up.

Thanks.

2. Joined: Oct 2008
Posts: 7,698
Likes: 1,570, Points: 113, Legacy Rep: 2488
Location: Japan

If you are a student, you have a long way to go. This is also one of the first simple calculations that is performed in Stability during your first year..

If you're a "designer", than i would suggest you're way out of your depth and should seek a professionally qualified naval architect.

It is simple:

GG= (W x d)/ (final displacement)

Where W = weight of object, and d = distance from current CoG to the objects CoG.

3. Joined: Aug 2002
Posts: 16,658
Likes: 1,619, Points: 123, Legacy Rep: 2031
Location: Milwaukee, WI

gonzoSenior Member

He posted an ad offering to pay a NA to do his homework. The guy is a cheat.

4. Joined: May 2011
Posts: 10
Likes: 0, Points: 0, Legacy Rep: -21
Location: UK, Scotland

DavidT03Junior Member

Its not homework its a project, im aloud to get help with it as im not a naval architect and im struggling with the calculations as ive never really done this before so back off and stop preaching all over the forum that im a cheat just because im doing anything i can do get this project finished. If it pisses you off that much gonzo i could change my request to a NA tutor but seriously... why the hell do you even care?

5. Joined: Aug 2002
Posts: 16,658
Likes: 1,619, Points: 123, Legacy Rep: 2031
Location: Milwaukee, WI

gonzoSenior Member

You posted that your lecturer asked you to do this project. You claim to be a student and that this is a school project. I care because we put a lot of effort into being professionals and people like you try to cheat and find shortcuts.

6. Joined: Jan 2003
Posts: 1,438
Likes: 59, Points: 0, Legacy Rep: 841
Location: Southern England

Tim BSenior Member

I think the general feeling on the forum is that we're worried that you're asking these questions if you're studying to be a Marine Engineer. You are clearly either unbelievably lazy or way out of your depth. In either case, you need to consider whether an engineering profession is really the right choice. Calculation of CG is about the most basic thing you need to do. It is also not hard to find on Google.

Analysis of marine structures (be they boats, rigs or whatever) goes a long way beyond the hydrostatic properties, and while we sometimes joke about the analysis we do know what we're talking about before the joke is made.

You have a lot to learn.

Tim B.

1 person likes this.

7. Joined: May 2004
Posts: 5,372
Likes: 258, Points: 93, Legacy Rep: 3380
Location: Italy (Garda Lake) and Croatia (Istria)

daiquiriEngineering and Design

You have choosen a wrong school, I'd say... You have a potential for being a good a lawyer.

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.