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Submarines and dynamic stability… rocket science?
Interesting thread this and I've been trying to visualize something to make it simpler to understand and I've just seen it through the window - the weathercock on our Church tower!
The C of G is equivalent to the pivot point (right?) and our weathercock has stern planes only (It is like an arrow) and so it is stable and points into the wind.
If you moved the pivot point further aft it would be less stable (more manoeuvrable!)
Note to self: I must try and convince our Vicar to put a cross section of a submarine on the tower, with bow planes preferably. (Unlikely because our Vicar is a lady and therefore unlikely to be a submarine enthusiast – more’s the pity!!)
Excuse my musings but I hope the mental picture helps. And Happy Easter by the way!
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<-------------------- You mean like this?
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"There are the assassins, the dealers in death. I am the Avenger!" - Captain Nemo
And seriously I think a weathervane does help us visualise how our models behave dynamically.
I think that the vane also shows that the hull form and plan area is also very important.
Models don't turn just by forces developed on dive planes but also by aerofoil effects which are changed by water flow over the planes i.e imagine bending the leading or trailing edge of the weathervane.
I've just been looking at the SCR back issues report on DVD and this topic was very well discused by a certain David Merriman with reference to Skip Asay in issue No 8 in 1992!
A very good, easy to understand (no maths at all) aricle discussing how controls work and describing surface effects, superstructure effects etc. with reference to full size and model subs.
Worth getting the DVD just for this and it could avoid recent members re-inventing the wheel.
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