Minimum Planing Speed

NoBozo · 09-09-2009, 10:48 AM

I can plane at about 18 indicated, with flaps @15 degrees, but the wake turbulence is brutal.

NB

NoRegrets · 09-09-2009, 10:54 AM

I have a soon to be targeted 18,000 lb (scale tested) vessel that easily gets up on plane at 28 MPH. 32 is the sweet spot where it feels like we are gliding on silk with the engines gently purring.

BroadHopper · 09-09-2009, 10:55 AM

To have a large wake at planing speed. Maybe I should have said:

Minimum planing speed that will create a small wake.

Based on my observations, once a boat is on plane, the wake goes down.

I hope everyone takes this into account when they vote.

Kracken · 09-09-2009, 11:11 AM

I can get the boat on plane at less than 20 mph but it is not easy. The main problem is the wake generated to get it on plane. The ideal way to get it on plane is get it out of the hole quickly, then ease of the throttle and trim it out. This generates the smallest wake. Conversely by easing it up on plane I do end up plowing thus pushing several tons of water that generate large wakes.

VtSteve · 09-09-2009, 11:48 AM

After Smart Tabs, my boat planes at about 20 now. The ideal small wake planing speed is at 28-30 mph. As stated above, gradual speed to plane, or to come off plane, results in larger wakes for a longer period of time. This has another adverse effect, that other small boats slow down as they come to the larger wakes.

NoBozo · 09-09-2009, 03:07 PM

I think the faster a (planing) hull goes, the smaller the wake will be. This is particularly true of the Deep "V" hull which usually has a 24 degree deadrise. This hull will leave less and less wake the faster it goes because it continues to climb further out of the water on the "V" and lifting strakes, reducing wetted surface...allowing it to go even faster.

A flat bottom planing hull, such as a hydroplane, will plane off earlier and with much less effort, and leave less wake. NB

PS: The power to weight ratio probably has as MUCH to do with it as hull shape I think.

XCR-700 · 09-09-2009, 03:29 PM

The numbers on the graph are interesting, and leave me asking what kind of boats were talking about and how the MPH is being measured.

I think you also need to consider how stable your boat is at minimum plane speed. i.e. will it fall of plane if the engine RPM varies at all or if you hit any wake, or correct direction.

In my mind minimum plane speed is the speed where my hull is up "on top of the water" and will stay there without me playing with the throttle every second and/or holding a dead straight path across flat water.

In real world conditions, engine RPM will vary 100-200, you will hit someone elses wake, and you will have to make directional corrections and that will all effect the speed at which the hull will stay on a plane.

For my current boats:

1988 Glastron Carlson CVX-20 w/225 Yamaha 2/stroke outboard the lowest speed it will stay on top is like 32 MPH

1989 Glastron Carlson CSS-23 w/Mercruiser I/O the lowest speed it will stay on top is like 28 MPH

In both cases thats with average loads (people and gear) and near full fuel tanks and using GPS.

I have to question if the majority of the folks responding are talking about very small boats (under 18') with light loads and borderline falling off plane, AND using some factory speedometer (NOT super accurate) as I just dont see a whole lot of boats that can hold a solid plane under 25 MPH and most that I have driven are closer to 30 MPH than 25 MPH.

Well thats my observation

GH

p.s. the 25 MPH exactly option seems like a useless number in my mind as no boat holds and exact speed for very long, grab a GPS and see for yourself! I think you should consider re-polling and split the groupings into 5 MPH chunks and better define the term plane to include the factors I have described above.

Kracken · 09-09-2009, 03:37 PM

The best way to eliminate harmful wakes is to either stay at headway speed or stay on plane. Starting and stopping along with plowing causes the largest wake.

There is no universal headway speed. Each hull design has its own maximum no wake speed. Size, shape and weight of the hull are the major factors that determine the maximum no wake speed. Some boats can go over 8 MPH without throwing a wake while others can’t go over 5 mph without throwing a wake. When a boater is in a NWZ he/she must understand the characteristics of their vessel and act accordingly.

The same can be said for minimum planing speed. Size, shape weight and power are the determining factors in planing. Some boats have no problem getting on plane at speeds less than 20 MPH, most do not. While they can be on plane at speeds under 25 they end up plowing to get on plane or exceed the speed limit to achieve it.

New Hampshire is not the only state with a night time speed limit (I know I am not supposed to talk about other states). But other states have laws that read 25 MPH max at night OR minimum planing speed.

So my question is simple. What do Winnipesaukee boaters and land owners want? A limit that causes erosion or just a limit?

XCR-700 · 09-09-2009, 04:23 PM

Quote:

Originally Posted by Kracken

So my question is simple. What do Winnipesaukee boaters and land owners want? A limit that causes erosion or just a limit?

Well said!!!

I like the language about minimum planing speed, seems reasonable at night.

As for daytime speedlimits, well best not open that can of worms,,, but I will say the number is worthless as people crash boats at all speeds, not just over a certain number.

GH

VtSteve · 09-09-2009, 04:33 PM

Quote:

Originally Posted by Kracken

So my question is simple. What do Winnipesaukee boaters and land owners want? A limit that causes erosion or just a limit?

I think most just want to go about their business and rest assured that the real nutcases on the lake will be dealt with accordingly.

"Some" want to gradually eliminate the people and boats "They" don't like. If you look through the old SL threads (now closed), you'll see what they are. We also had some great discussions last year about boats and wakes. Some pretty interesting comments

In short, "they" want to eliminate anything "they" don't like. It's a moving target.

Anybody that's ever driven a boat in a bay on a weekend knows full well what happens when people plow along due to congestion.

View Poll Results: What is the Minimum Planing Speed of your boat
less than 25 mph	78	57.35%
25 mph	18	13.24%
between 26 and 30 mph	32	23.53%
greater than 30 mph	8	5.88%
Voters: 136. You may not vote on this poll

09-09-2009, 10:55 AM	#3
BroadHopper Senior Member Join Date: Oct 2004 Location: Laconia NH Posts: 5,586 Thanks: 3,228 Thanked 1,107 Times in 797 Posts	Interesting To have a large wake at planing speed. Maybe I should have said: Minimum planing speed that will create a small wake. Based on my observations, once a boat is on plane, the wake goes down. I hope everyone takes this into account when they vote. __________________ Someday may never be an actual day.

09-09-2009, 03:29 PM	#7
XCR-700 Senior Member Join Date: Sep 2008 Location: MA Posts: 1,342 Thanks: 757 Thanked 538 Times in 313 Posts	The numbers on the graph are interesting, and leave me asking what kind of boats were talking about and how the MPH is being measured. I think you also need to consider how stable your boat is at minimum plane speed. i.e. will it fall of plane if the engine RPM varies at all or if you hit any wake, or correct direction. In my mind minimum plane speed is the speed where my hull is up "on top of the water" and will stay there without me playing with the throttle every second and/or holding a dead straight path across flat water. In real world conditions, engine RPM will vary 100-200, you will hit someone elses wake, and you will have to make directional corrections and that will all effect the speed at which the hull will stay on a plane. For my current boats: 1988 Glastron Carlson CVX-20 w/225 Yamaha 2/stroke outboard the lowest speed it will stay on top is like 32 MPH 1989 Glastron Carlson CSS-23 w/Mercruiser I/O the lowest speed it will stay on top is like 28 MPH In both cases thats with average loads (people and gear) and near full fuel tanks and using GPS. I have to question if the majority of the folks responding are talking about very small boats (under 18') with light loads and borderline falling off plane, AND using some factory speedometer (NOT super accurate) as I just dont see a whole lot of boats that can hold a solid plane under 25 MPH and most that I have driven are closer to 30 MPH than 25 MPH. Well thats my observation GH p.s. the 25 MPH exactly option seems like a useless number in my mind as no boat holds and exact speed for very long, grab a GPS and see for yourself! I think you should consider re-polling and split the groupings into 5 MPH chunks and better define the term plane to include the factors I have described above. Last edited by XCR-700; 09-09-2009 at 10:25 PM.

09-09-2009, 10:48 AM	#1
NoBozo Senior Member Join Date: Jun 2008 Location: Portsmouth. RI Posts: 2,231 Thanks: 400 Thanked 460 Times in 308 Posts	I can plane at about 18 indicated, with flaps @15 degrees, but the wake turbulence is brutal. NB

09-09-2009, 10:54 AM	#2
NoRegrets Senior Member Join Date: Jun 2007 Location: Hudson - NH Posts: 408 Thanks: 233 Thanked 212 Times in 88 Posts	I have a soon to be targeted 18,000 lb (scale tested) vessel that easily gets up on plane at 28 MPH. 32 is the sweet spot where it feels like we are gliding on silk with the engines gently purring.

09-09-2009, 11:11 AM	#4
Kracken Senior Member Join Date: Jul 2009 Location: Alton Posts: 223 Thanks: 46 Thanked 130 Times in 50 Posts	I can get the boat on plane at less than 20 mph but it is not easy. The main problem is the wake generated to get it on plane. The ideal way to get it on plane is get it out of the hole quickly, then ease of the throttle and trim it out. This generates the smallest wake. Conversely by easing it up on plane I do end up plowing thus pushing several tons of water that generate large wakes.

09-09-2009, 11:48 AM	#5
VtSteve Senior Member Join Date: Apr 2008 Posts: 1,320 Blog Entries: 1 Thanks: 230 Thanked 361 Times in 169 Posts	After Smart Tabs, my boat planes at about 20 now. The ideal small wake planing speed is at 28-30 mph. As stated above, gradual speed to plane, or to come off plane, results in larger wakes for a longer period of time. This has another adverse effect, that other small boats slow down as they come to the larger wakes.

09-09-2009, 03:07 PM	#6
NoBozo Senior Member Join Date: Jun 2008 Location: Portsmouth. RI Posts: 2,231 Thanks: 400 Thanked 460 Times in 308 Posts	I think the faster a (planing) hull goes, the smaller the wake will be. This is particularly true of the Deep "V" hull which usually has a 24 degree deadrise. This hull will leave less and less wake the faster it goes because it continues to climb further out of the water on the "V" and lifting strakes, reducing wetted surface...allowing it to go even faster. A flat bottom planing hull, such as a hydroplane, will plane off earlier and with much less effort, and leave less wake. NB PS: The power to weight ratio probably has as MUCH to do with it as hull shape I think.

09-09-2009, 03:37 PM	#8
Kracken Senior Member Join Date: Jul 2009 Location: Alton Posts: 223 Thanks: 46 Thanked 130 Times in 50 Posts	The best way to eliminate harmful wakes is to either stay at headway speed or stay on plane. Starting and stopping along with plowing causes the largest wake. There is no universal headway speed. Each hull design has its own maximum no wake speed. Size, shape and weight of the hull are the major factors that determine the maximum no wake speed. Some boats can go over 8 MPH without throwing a wake while others can’t go over 5 mph without throwing a wake. When a boater is in a NWZ he/she must understand the characteristics of their vessel and act accordingly. The same can be said for minimum planing speed. Size, shape weight and power are the determining factors in planing. Some boats have no problem getting on plane at speeds less than 20 MPH, most do not. While they can be on plane at speeds under 25 they end up plowing to get on plane or exceed the speed limit to achieve it. New Hampshire is not the only state with a night time speed limit (I know I am not supposed to talk about other states). But other states have laws that read 25 MPH max at night OR minimum planing speed. So my question is simple. What do Winnipesaukee boaters and land owners want? A limit that causes erosion or just a limit?

The Following User Says Thank You to Kracken For This Useful Post:
XCR-700 (09-09-2009)

The Following User Says Thank You to VtSteve For This Useful Post:
NoRegrets (09-09-2009)