Click for Glendinning Click for Cross Click for Walker Click for Delta Click for YF Listing Service

Humpfree Interceptor System

Discussion in 'Stabs, Tabs & Gyros' started by CaptGDunz, Oct 10, 2013.

You need to be registered and signed in to view this content.
  1. CaptGDunz, Oct 10, 2013
    #1
    CaptGDunz

    CaptGDunz Member

    Joined:
    Mar 24, 2009
    Messages:
    60
    Location:
    Jersey Shore (North)
    HUMPHREE Interceptor Trim Tab System - YouTube

    Anyone have experience with Humpfree Interceptors on 100' class yachts? I have a customer considering them to improve performance and efficiency.

    I have used fixed interceptors on High Speed Ferries and the effect on trim and performance was remarkable.
  2. AMG, Oct 10, 2013
    #2
    AMG

    AMG YF Moderator

    Joined:
    Jul 26, 2004
    Messages:
    5,378
    Location:
    Sweden
    We have them on our IPS boats as a part of the design. The Delta 54 often likes to be trimmed down in the bow and it does not take away any speed. On the new Delta 80 IPS we have them too and they seems to work well, but I have not yet driven the boat. On both boats we have them in combination with a Seakeeper gyro which seems to work well also at higher speeds. In our experience, you should go up in tab size from the recommended though...
  3. CaptGDunz, Oct 13, 2013
    #3
    CaptGDunz

    CaptGDunz Member

    Joined:
    Mar 24, 2009
    Messages:
    60
    Location:
    Jersey Shore (North)
    These boats did 29 knots with 2 x 1760 hp when new with a full load of passengers. With an engine down they would only do 11 knots. After they where fit with simple fixed interceptors they did 20 -21 knots on one engine. A picture of the interceptor to follow.

    Attached Files:

  4. CaptGDunz, Oct 13, 2013
    #4
    CaptGDunz

    CaptGDunz Member

    Joined:
    Mar 24, 2009
    Messages:
    60
    Location:
    Jersey Shore (North)
    Fixed Interceptor

    Attached Files:

  5. CaptGDunz, Oct 13, 2013
    #5
    CaptGDunz

    CaptGDunz Member

    Joined:
    Mar 24, 2009
    Messages:
    60
    Location:
    Jersey Shore (North)
    The effect was amazing. Lobster boats used to do it by running a deck line under the boat between stern bits and pulling it tight with a come along.

    Attached Files:

  6. K1W1, Oct 13, 2013
    #6
    K1W1

    K1W1 Senior Member

    Joined:
    Sep 30, 2005
    Messages:
    7,394
    Location:
    My Office
    Hi,

    I asked a very well known Naval Architect about this type of arrangement and was told that a large improvement will be seen for sure if the hull was not very efficient originally.

    He stressed the importance of thorough testing and optimising of the lines followed by CFD and Tank Testing to achieve the best results.

    So far we are very happy with the CFD results and the work he is doing for us on a large displacement vessel that will get along at just over 20 kts with around 11,500 hp.
  7. AMG, Oct 13, 2013
    #7
    AMG

    AMG YF Moderator

    Joined:
    Jul 26, 2004
    Messages:
    5,378
    Location:
    Sweden
    This is true, especially on a displacement boat, but you can also design a hull for interceptors. On our 54 which is a planing hull with IPS drives, you'll need some kind of trim for different sea and wind. So without trim, she goes a little high with the bow and then you can trim down when necessary, something that is not possible with IPS.