Click for Cheoy Lee Click for Abeking Click for Nordhavn Click for Seacoast Click for Mag Bay

Zero Speed Stabilizers?

Discussion in 'Stabs, Tabs & Gyros' started by rmjranch, Jan 24, 2014.

You need to be registered and signed in to view this content.
  1. rmjranch

    rmjranch Member

    Joined:
    Mar 6, 2011
    Messages:
    61
    Location:
    Ft Lauderdale FL
    General thoughts on Zero Speed Stabilizers, from people who have been on boats with them.
    #1 Do they work?
    #2 Noisy?
    #3 Reliable?
    #4 Great or not so great?
    #5 Brand, if that is allowed on this forum.
    Any and all information greatly appreciated, including the SIZE of the boat you were on.
    Thanking you in advance.
  2. Capt Bill11

    Capt Bill11 Senior Member

    Joined:
    Feb 27, 2006
    Messages:
    1,436
    Location:
    Sarasota/Ft. Lauderdale FL
    #1 Yes
    #2 Can be. But if installed correctly with an eye towards proper sound proofing, not really.
    #3 The boat I was on that had them has had them up and running with no problems for well over a year now.
    #4 Great! Once you have them you will not want to be without them IMO.
    #5 TRAC With good after the sale service.

    Boat size - 140'

    For more info call TRAC and ask for Justin.
  3. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    8,741
    Location:
    Satsuma, FL
    Justin also knows CPR; for when you hear the price..
  4. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    12,760
    Location:
    Fort Lauderdale
    I only worked on one yacht that had them. a 160' Delta, I believe they were trac, not positive. They did a great job, we didn't hear them at all even down in the crew area's (lowest living spaces in the yacht.

    As for the expense, if you have to ask the price then you can't afford it. hehehe
  5. C4ENG

    C4ENG Senior Member

    Joined:
    May 19, 2006
    Messages:
    581
    Location:
    Ft Lauderdale
    #2 noise. The actual movement of the fins through the water is not noisy. A lot of times there is a bed on top of the fin actuators (where the hydraulic rams are moving the fins) and who ever sleeps in that bed will hear a dampened swish noise all night. The hydraulics of the system can get noisy through the boat if the nitro filled noise suppressor looses some of its charge. They do need to be charged every year (or at least checked).

    Quantum is what I am most experienced with.
    And they are reliable when you do what the manufacture suggest in ways of maintenance.
    150 to 200 ft vessels.

    The worst thing about zero speed stabilizers is once you are accustomed to having them, it's horrible with out them
  6. K1W1

    K1W1 Senior Member

    Joined:
    Sep 30, 2005
    Messages:
    7,393
    Location:
    My Office
    Hi,

    Here are my thoughts and experiences with Quantum Systems.

    Yes to a certain extent they will improve the feeling for the folks onoard when stopped and or at anchor.

    Not any distance from the machine itself if properly installed and pipe runs are kept to a minimum

    In my experience yes, very. Things like spherical bearngs do wear and there is maintenance required.

    A great system that allows some Owners and Charters who would otherwise be unable to enjoy yachting to also partake of its pleasures.

    +1 for Quantum a company that has continually strived to update and improve their offerings and who now also have an alternative system to the traditional fins arrangement.

    It is called Mag Lift and holds great promise to work quite a lot better than the fin system.

    70 and 80m, currently looking at them for a much larger one.
  7. Fishtigua

    Fishtigua Senior Member

    Joined:
    Jul 20, 2007
    Messages:
    2,695
    Location:
    Guernsey/Antigua
    Quantum, the Zero Speed people, are a Guernsey based company. Their offices are just up the road from me. I've worked on 2 boats with them fitted and, to be honest, couldn't tell if they were on or off.

    I suppose, over many years, that I've become immune to the feeling of any rocking and rolling aboard.

    Now if my beer were to ever start to spill.....................?:D

    Zerospeed | Quantum Med Marine
  8. K1W1

    K1W1 Senior Member

    Joined:
    Sep 30, 2005
    Messages:
    7,393
    Location:
    My Office
    Hi,

    Fish, This is the HQ and incorporates one of the most well known and respected Stabiliser Gurusin the shape of Peter Florence and where most of the R and D is done although they have been doing some with Delft University for the last 2 yrs which has caused a major rethink in why some of this stuff works.

    Stabilizers | Integrated Systems | Quantum Marine Engineering
  9. HTMO9

    HTMO9 Senior Member

    Joined:
    Jan 13, 2009
    Messages:
    1,380
    Location:
    Europe
    Rolling stabilisation

    For displacement or semi displacement hulls, I would sign all statement above. TRAC systems for boats up to 100 / 130 ft and Quantum for almost everything bigger. For much larger steel boats, for example in the 3000 GT range, I personally would go for the fully retractable zero speed fins from Blohm & Voss Industries.

    But from personal experience gained in the last year, for fast planning hulls up to 500 GT, I would go for gyroscopic antiroll stabilisation, either in single or multiple configuration. But only with the Seakeeper systems and not with the noisy devil in the box, Mitsubishi ARG systems.

    The most interesting zero speed stabilisation system using hydraulic fins, I have seen on a yacht, that was built in the very northeastern part of the Med. The system was only powered by main engine driven PTO pumps :eek:.
  10. K1W1

    K1W1 Senior Member

    Joined:
    Sep 30, 2005
    Messages:
    7,393
    Location:
    My Office
    Hi,

    They require such a big envelope you better add another 500 ton to the volume.

    Look at the Mag Lift System, it has come a long way since the earliest ones were produced.
  11. Fishtigua

    Fishtigua Senior Member

    Joined:
    Jul 20, 2007
    Messages:
    2,695
    Location:
    Guernsey/Antigua
    Developed at HDW. I know, I was there.
  12. HTMO9

    HTMO9 Senior Member

    Joined:
    Jan 13, 2009
    Messages:
    1,380
    Location:
    Europe
    KIWI your a correct, they take some internal volume for their pockets. And you got me on these Quantum stabilizers. I saw them, when I walked through the floating dock at B&V with Eclipse in it but I did not really noticed them and later forgot to ask.

    Are these the onces that can be seen on this picture of Ecplipse in dock ? How effective are they in comparison to the retractable fins? When I remember correctly, Eclipse had four of them.

    Attached Files:

  13. K1W1

    K1W1 Senior Member

    Joined:
    Sep 30, 2005
    Messages:
    7,393
    Location:
    My Office
    Hi,

    They have been shown to be much more effective as they are always moving.

    The biggest drawback with them is they are limited to a top speed of somewhere around 16/17kts.

    They have shown themselves to be particularly effective at no and slow speeds that a lot of patrol boats are tasked with doing these days.

    There is no dead period when slowing down in the anchorage and they will also work when going astern - something that no fin will do as far as I am aware.

    They also do not make the vessel tend to swim around as they operate at anchor.
  14. Milow232

    Milow232 Senior Member

    Joined:
    Sep 13, 2011
    Messages:
    1,509
    Location:
    Germany
    May I ask what is the reason for the limited speed? And why does this not apply for retractable stabilizers?
  15. HTMO9

    HTMO9 Senior Member

    Joined:
    Jan 13, 2009
    Messages:
    1,380
    Location:
    Europe
    Speed limit on stabilizers

    Retractable stabilizers extend backwards towards a mechanical stop and held open by the flow of water. The faster the ship goes, the smaller the movements of the fin, same as on rudders on aircraft. They are strong enough for higher speeds and still work at higher speeds but only in one direction because of its hydrodynamic profile.

    The principle of the new Quantum MAGLIFT retractable stabilizers is based on the "Magnus effect". Which means, the air flow around the side of a rotating cylinder, which rotates with the flow, is greater than on the other side causing a slight pressure difference. This creates lift. This phenomena is used for roll stabilisation. In addition, besides its bidirectional rotation, the cylinder moves forward and backwards during its rotation to create this kind of lift during zero speed situations.

    But this effect will die during higher boat speeds and the cylinder will only have an symmetrical flow around it, the lift will be destroyed within the boundary layer and because of its head resistance, the extended cylinder gets counter productive and it is better to retract them. When you look at the animated videos, it seems funny, how this cylinders paddle around during their zero speed work but they really seem to work.

    I do not believe, they have to be retracted, because they are unable to withstand the waterpressure at higher boat speeds but because of their greater angle of movement beyond the rectangular position, they have to be positioned by hydraulic force and not by a mechanical stop.

    The vertical Flettner Rotor (for example used on the E-ship 1) uses this Magnus Effect to add in propulsion of a ship. The fuel saving have been up as high as 25 %, using these rotors on that cargo vessel. But on this vertical rotors, big endplates (like winglets on a/c) increase the effiency remarkably. These endplates would not work on the stabilizers because of their additional freedom of movement. The above mentioned Magnus effect should not be mistaken with the Coandă effect, which is far more complicated (to explain) in the 3D world.

    I hope, my limited command of the english language could explain this complicated subject a little bit.

    Magnus effect:

    Attached Files:

  16. K1W1

    K1W1 Senior Member

    Joined:
    Sep 30, 2005
    Messages:
    7,393
    Location:
    My Office
    Hi,

    I am led to understand from the Manufacturers that this is why they pull them back, they also say that folding them back does not seem to have any reduction in the stabilisation force.
  17. HTMO9

    HTMO9 Senior Member

    Joined:
    Jan 13, 2009
    Messages:
    1,380
    Location:
    Europe
    Aerodynamics

    This complicated subject makes comming back my nightmares from university in the night before an exam, when the last things in my brain before falling asleep, were Mr. Magnus, Mr. Coandă, Mr. Bernoulli, Mr. Flettner and Mr. Boyle–Mariotte and their friends with all their rules, laws and formulars :D.

    "Chemistry is bang and smell and physics never work", old saying from students since centuries.