how is a rooster tail formed?
02-10-2008, 02:56 AM
#3
RE: how is a rooster tail formed?
to expand on Dan's reply, the roostertail is water thrown up by the prop blades as they spin out of the water. As already stated, the depth and thrust angle on the prop will affect how much of a tail you get. Beyond this, RPM as well as blade shape and modifications also have an affect on te tail. One thing to remember is that too high of tail means you are not getting all the thrust you could be
02-10-2008, 11:16 PM
#5
Senior Member
Join Date: Aug 2004
Location: rockawaybeach,
MO
Posts: 156
Likes: 0
Received 0 Likes
on
0 Posts
RE: how is a rooster tail formed?
Cavitation happens when the rpm of the prop is greater than the flow of water
into the prop creating a air pocket around the prop & not letting water into the blades
to provide thrust
a rooster tail is just water existing the rear of the prop moving at high speed hitting slow
or none moving water & breaking the surface tension of the water & spraying in the air
This is about as techy as i can get on this subject [8D]
Hope this helps
into the prop creating a air pocket around the prop & not letting water into the blades
to provide thrust
a rooster tail is just water existing the rear of the prop moving at high speed hitting slow
or none moving water & breaking the surface tension of the water & spraying in the air
This is about as techy as i can get on this subject [8D]
Hope this helps
for the hen
..just messing around..
02-12-2008, 10:53 AM
#7
RE: how is a rooster tail formed?
Some people forget that Cavatitation and or Ventalation can cause a frothy prop wash.
My overpowered 19' V hull can do either if I want to. I can Cavatate in 2 seconds from a dead stop. The prop accelerates so fast that the water can not flow to the prop fast enough. The water pressure drop is so low at the props surface, that the water starts to create air bubbles & then the prop loses all bite.
I can also Ventilate the prop at maximum speed by trimming the sterndrive up to much. NICE ROOSTER TAIL. Boat is actually running slower by GPS. Engine goes into revolution limiter.
Rich
02-16-2008, 12:17 PM
#8
Senior Member
My Feedback: (48)
Join Date: Mar 2003
Location: Gulf Shores, AL
Posts: 1,885
Likes: 0
Received 0 Likes
on
0 Posts
RE: how is a rooster tail formed?
ORIGINAL: cyclops2
Some people forget that Cavatitation and or Ventalation can cause a frothy prop wash.
My overpowered 19' V hull can do either if I want to. I can Cavatate in 2 seconds from a dead stop. The prop accelerates so fast that the water can not flow to the prop fast enough. The water pressure drop is so low at the props surface, that the water starts to create air bubbles & then the prop loses all bite.
I can also Ventilate the prop at maximum speed by trimming the sterndrive up to much. NICE ROOSTER TAIL. Boat is actually running slower by GPS. Engine goes into revolution limiter.
Rich
Some people forget that Cavatitation and or Ventalation can cause a frothy prop wash.
My overpowered 19' V hull can do either if I want to. I can Cavatate in 2 seconds from a dead stop. The prop accelerates so fast that the water can not flow to the prop fast enough. The water pressure drop is so low at the props surface, that the water starts to create air bubbles & then the prop loses all bite.
I can also Ventilate the prop at maximum speed by trimming the sterndrive up to much. NICE ROOSTER TAIL. Boat is actually running slower by GPS. Engine goes into revolution limiter.
Rich
Yeah, but your 'overpowered' v hull is most likely running a prop that would have exhaust gasses passing through it. Not sure you can compare here.
Typically speaking, the lower the rooster tail, the faster the speed. This is true for both fullscale & models.
Don't get me wrong, its part of running boats that I enjoy. To add to what cyclops2 is saying, I have a friend who was running a large mono. Roost was almost straight up & long. Looked cool, but no speed. A few adjustments & prop changes had him going a bit better.
02-17-2008, 10:10 AM
#9
My Feedback: (12)
Join Date: Jun 2004
Location: Columbia,
SC
Posts: 8,044
Likes: 0
Received 0 Likes
on
0 Posts
RE: how is a rooster tail formed?
ORIGINAL: Doubledog
Yeah, but your 'overpowered' v hull is most likely running a prop that would have exhaust gasses passing through it. Not sure you can compare here.
ORIGINAL: cyclops2
Some people forget that Cavatitation and or Ventalation can cause a frothy prop wash.
My overpowered 19' V hull can do either if I want to. I can Cavatate in 2 seconds from a dead stop. The prop accelerates so fast that the water can not flow to the prop fast enough. The water pressure drop is so low at the props surface, that the water starts to create air bubbles & then the prop loses all bite.
I can also Ventilate the prop at maximum speed by trimming the sterndrive up to much. NICE ROOSTER TAIL. Boat is actually running slower by GPS. Engine goes into revolution limiter.
Rich
Some people forget that Cavatitation and or Ventalation can cause a frothy prop wash.
My overpowered 19' V hull can do either if I want to. I can Cavatate in 2 seconds from a dead stop. The prop accelerates so fast that the water can not flow to the prop fast enough. The water pressure drop is so low at the props surface, that the water starts to create air bubbles & then the prop loses all bite.
I can also Ventilate the prop at maximum speed by trimming the sterndrive up to much. NICE ROOSTER TAIL. Boat is actually running slower by GPS. Engine goes into revolution limiter.
Rich
Yeah, but your 'overpowered' v hull is most likely running a prop that would have exhaust gasses passing through it. Not sure you can compare here.
02-17-2008, 11:29 AM
#10
RE: how is a rooster tail formed?
I love a transom exhaust !! Except when I have people aboard and we are talking all over the boat.
Mine is a 220 HP sterndrive. Underwater prop exhaust. [:'(]
Rich
02-17-2008, 09:07 PM
#11
Senior Member
Join Date: Jul 2006
Location: Whitewater, KS
Posts: 189
Likes: 0
Received 0 Likes
on
0 Posts
RE: how is a rooster tail formed?
It refers to big boats but download this http://users.cybercity.dk/~ccc53569/prop_001.htm It is everything you wanted to know about propellers...well almost
Kelly
Kelly
02-17-2008, 09:28 PM
#12
Senior Member
Join Date: Jul 2006
Location: Whitewater, KS
Posts: 189
Likes: 0
Received 0 Likes
on
0 Posts
RE: how is a rooster tail formed?
This is an very detailed article that i would suggest also http://www.simplicity-marine.com/surfprop.htm I am sorrry it really won't say a lot about rootertails but it will sure explain the difference between cavitation and venalation as well as a lot of other stuff. propbably one of the best propeller information (surface drive) I have seen.
Kelly
Kelly
