Results 1 to 12 of 12

Thread: Jetboat Spin Video

  1. #1

    Default Jetboat Spin Video

    Video clip of trying to do a 180 spin in a 20ft Wooldridge Sport outboard jetboat. Steered a little to port the cranked the wheel with suicide knob to full starboard while keeping under 3/4 throttle the whole time. Tried the deal wear you switch to neutral and then crank to the other side but I was not able to do all that fast enough to keep up with the spin. Nowhere near competent enough yet to try this under tight quarters. My bow never went down much like I see other boats do in videos, but the water almost sloshes over the back corner. Would be nervous trying this in moving water for fear of swamping the back corner.

    Any comments on technique or risk of swamping ?

    http://www.youtube.com/watch?v=sGrYGxr6su0

  2. #2
    Moderator LuJon's Avatar
    Join Date
    Mar 2007
    Location
    Palmer, AK
    Posts
    11,415

    Default

    I am interested in hearing comments too! I have practiced this many times in lakes and it is a little unnerving to see the back settle into that trough knowing nothing good can come from that wall of water breaking over the side and filling that "hole" in the water that stands between you and swimming.

  3. #3
    Member
    Join Date
    Apr 2008
    Posts
    1,892

    Default

    I just learn here last year. The more speed the better.

  4. #4
    Member Dirtofak's Avatar
    Join Date
    Apr 2006
    Location
    Beaver Creek
    Posts
    2,267

    Default

    When I spin hard, the nose dives under the water!

  5. #5
    Member
    Join Date
    Apr 2006
    Location
    Anchorage
    Posts
    3,293

    Default

    When I spun my boat 180* it came around faster than I was anticipating. I found myself going downstream backwards at 30mph. The bow attitude never concerned me. The water pouring over the transom had my full attention! The stern was pushing water, the jet was cavitating, and my passengers were scared to death. Not as much fun as the bar room stories make it up to be.

  6. #6
    Member skybust's Avatar
    Join Date
    Oct 2006
    Location
    alaska
    Posts
    2,426

    Default

    Its a blast in my SJX I learned how to do it in my wooly classic and that almost made me crap my pants when the bow went under the water and it came up and hit the wind sheild

  7. #7
    Member Jimw's Avatar
    Join Date
    Jul 2006
    Location
    Alaska
    Posts
    453

    Default

    looked smooth to me. good to know how if the need arises.
    2005 20' Weldcraft Sabre XL 350 MP
    SD309 AT
    2009 Polaris Dragon 800 163
    Custom Mod's

  8. #8
    Member
    Join Date
    Apr 2006
    Location
    Anchorage
    Posts
    3,293

    Default

    Looked smooth because he had a gigantic calm lake with no obstacles. Plus he was going slow to begin with and sitting dead in the water at the end. That doesn't resemble any jet boating I'm familiar with. At least none where performance maneuvering is important. Come down lake Creek at full speed and try it.

  9. #9
    Member alaskabliss's Avatar
    Join Date
    Jul 2008
    Location
    Wasilla
    Posts
    1,419

    Default Be carefull

    Just my two cents worth on doing spins with these boats.

    I feel it's important to know how to do a spin in a emergency but watch your RPM's when you spin around and start cavitating. It can be hard to pull back on the throttle and your engin will spike to some pretty high RPM's.
    I was having some work done on my T jet and the mechanic asked me if I was doing spins with it. He could see on the computer where my RPM's had peaked at 5200 RPM's. The Hamilton 212 is only rated to 5K and the motor not much more. They had another boat in that was hitting over 6K RPM's doing spins and toasted the motor. Warranty was denied.

    I have learned that full reverse works almost as well and when im in a bind a little slower turn while feeding throttle gets me turned around while staying on step in the shallows.

  10. #10

    Default swamping the stern

    It seems that in river water moving at a half way decent speed that if you spin while running downstream the current would help to carry the stern wave away from the boat and you would be less likely to swamp (i.e. the stern is down river at the end of the spin).

    It also seems that if you spin while running upstream the exact opposite would happen and the wave would be higher because the boat is pushing water against the current (i.e the the stern is up river at the end of the spin), and then the current would make it return back towards the stern of the boat even faster and you would most likely swamp it .

    I carefully worked my way up in 1 mph increments to see how the boat reacted. The video clip was done with the boat at 24 mph on a lake. Imagine the wave generated if you are going 30 mph upstream (gps land speed) and swing the stern around into current moving downstream at the typical 5 to 7 mph.

    It also seems that the bow does not go down so much. What is really happening is the stern comes up as it rides over the wave being pushed by the keel and therefore drives the bow down. The stern is moving the fastest because it is at the outside of the spin and it therefore pushes the most water. Whereas the bow is barely moving and was not in the water to begin with so it gets driven down by rising stern. At least with the bow you don't have a return wave filling the hole created by the boat like you do at the stern. I have a self draining bow (with oversize drain holes) but don't have a self draining rear deck..........

    I left the throttle down until it started to cavitate, then immediately backed it off. For whatever reason, my boat spins easilly clockwise, but not as easilly counter clockwise. Not sure if the kicker dipped in on the clockwise spin. It did not dip in on the counterclockwise spin shown in the video.

    I find myself blathering on a bit................. In conclusion I would not try this in a river with any noticeable current unless I had one of those funky boats designed for spinning like they do in New Zealand.

  11. #11
    Moderator LuJon's Avatar
    Join Date
    Mar 2007
    Location
    Palmer, AK
    Posts
    11,415

    Default

    your boat is a bit bigger than mine but I attributed the ease of the clockwise spin to the location of the helm and most importantly the 270 lbs paluka standing behind it. If I weight the other side of the boat to balance it out then it spins pretty much the same either direction.

    I mostly agree with your assessment about spinning upstream. So far I have not found the need to spin upstream as much as going down. Upstream if I get into trouble I can back off to just barely on step goose it broadside and let the current spin me around.

  12. #12
    Member Yukoner's Avatar
    Join Date
    Aug 2007
    Location
    Whitehorse Yukon
    Posts
    1,344

    Default

    "Nice whip around"
    Your wifes commentary? At least your wife seems enthused, my wife would (and does) call me a jack *****
    Compared to my old Ak, the Sport with the wider hull really slides around, which I like. Honestly, looking at your spin, it didn't look like you were anywhere near taking water of any significance over the transom, I think its just perception. I felt the same way the first few times I tried it in my Sport. Happens quick, and lots of bouncing and splashing, but a loooong way from swamping I think (hope?)
    Cheers
    Paul
    Never wrestle with a pig.
    you both get dirty;
    the Pig likes it.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •